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Shah SB, Wang Y, Anwar N, Abbas SZ, Khan KA, Wang SM, Ullah MW. Co-metabolic degradation and metabolite detection of hexabromocyclododecane by Shewanella oneidensis MR-1. Appl Microbiol Biotechnol 2024; 108:25. [PMID: 38157005 DOI: 10.1007/s00253-023-12905-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 01/03/2024]
Abstract
Hexabromocyclododecane (HBCD) is a widely used brominated flame retardant; however, it is a persistent organic pollutant as well as affects the human thyroid hormones and causes cancer. However, the degradation of HBCD has received little attention from researchers. Due to its bioaccumulative and hazardous properties, an appropriate strategy for its remediation is required. In this study, we investigated the biodegradation of HBCD using Shewanella oneidensis MR-1 under optimized conditions. The Box-Behnken design (BBD) was implemented for the optimization of the physical degradation parameters of HBCD. S. oneidensis MR-1 showed the best degradation performance at a temperature of 30 °C, pH 7, and agitation speed of 115 rpm, with an HBCD concentration of 1125 μg/L in mineral salt medium (MSM). The strain tolerated up to 2000 μg/L HBCD. Gas chromatography-mass spectrometry analysis identified three intermediates, including 2-bromo dodecane, 2,7,10-trimethyldodecane, and 4-methyl-1-decene. The results provide an insightful understanding of the biodegradation of HBCD by S. oneidensis MR-1 under optimized conditions and could pave the way for further eco-friendly applications. KEY POINTS: • HBCD biodegradation by Shewanella oneidensis • Optimization of HBCD biodegradation by the Box-Behnken analysis • Identification of useful metabolites from HBCD degradation.
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Affiliation(s)
- Syed Bilal Shah
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Yiting Wang
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Naveed Anwar
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Syed Zaghum Abbas
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China
| | - Khalid Ali Khan
- Applied College, Mahala Campus and the Unit of Bee Research and Honey Production/Research Center for Advanced Materials Science (RCAMS), King Khalid University, P.O. Box 9004, Abha, 61413, Saudi Arabia
| | - Song-Mei Wang
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China.
| | - Muhammad Wajid Ullah
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, 212013, China.
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Huang C, Zeng Y, Hu K, Jiang Y, Zhang Y, Lu Q, Liu YE, Gao S, Wang S, Luo X, Mai B. Anaerobic biotransformation of two novel brominated flame retardants: Kinetics, isotope fractionation and reaction mechanisms. Water Res 2023; 243:120360. [PMID: 37481998 DOI: 10.1016/j.watres.2023.120360] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 07/12/2023] [Accepted: 07/14/2023] [Indexed: 07/25/2023]
Abstract
1,2,5,6-tetrabromocyclooctane (TBCO) and 2,3-dibromopropyl-2,4,6-tribromophenyl ether (DPTE), as safer alternatives to traditional brominated flame retardants, have been extensively detected in various environmental media and pose emerging risks. However, much less is known about their fate in the environment. Anaerobic microbial transformation is a key pathway for the natural attenuation of contaminants. This study investigated, for the first time, the microbial transformation behaviors of β-TBCO and DPTE by Dehalococcoides mccartyi strain CG1. The results indicated that both β-TBCO and DPTE could be easily transformed by D. mccartyi CG1 with kobs values of 0.0218 ± 0.0015 h-1 and 0.0089 ± 0.0003 h-1, respectively. In particular, β-TBCO seemed to undergo dibromo-elimination and then epoxidation to form 4,5-dibromo-9-oxabicyclo[6.1.0]nonane, while DPTE experienced debromination at the benzene ring (ortho-bromine being removed prior to para-bromine) rather than at the carbon chain. Additionally, pronounced carbon and bromine isotope fractionations were observed during biotransformation of β-TBCO and DPTE, suggesting that C-Br bond breaking is the rate-limiting step of their biotransformation. Finally, coupled with identified products and isotope fractionation patterns, β-elimination (E2) and Sn2-nucleophilic substitution were considered the most likely microbial transformation mechanisms for β-TBCO and DPTE, respectively. This work provides important information for assessing the potential of natural attenuation and environmental risks of β-TBCO and DPTE.
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Affiliation(s)
- Chenchen Huang
- School of Environmental Science & Spatial Informatics, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, Hangzhou 310015, China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
| | - Keqi Hu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yiye Jiang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Yanting Zhang
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Qihong Lu
- School of Environmental Science and Engineering, Sun Yat-sen University, China
| | - Yin-E Liu
- School of Environmental Science & Spatial Informatics, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Shutao Gao
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Shanquan Wang
- School of Environmental Science and Engineering, Sun Yat-sen University, China
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China; Guangdong-Hong Kong-MaCao Joint Laboratory for Environmental Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China
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3
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Ntungwe E, Domínguez-Martín EM, Bangay G, Garcia C, Guerreiro I, Colombo E, Saraiva L, Díaz-Lanza AM, Rosatella A, Alves MM, Reis CP, Passarella D, Rijo P. Self-Assembly Nanoparticles of Natural Bioactive Abietane Diterpenes. Int J Mol Sci 2021; 22:ijms221910210. [PMID: 34638551 PMCID: PMC8508833 DOI: 10.3390/ijms221910210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2021] [Revised: 09/10/2021] [Accepted: 09/16/2021] [Indexed: 11/16/2022] Open
Abstract
Different approaches have been reported to enhance penetration of small drugs through physiological barriers; among them is the self-assembly drug conjugates preparation that shows to be a promising approach to improve activity and penetration, as well as to reduce side effects. In recent years, the use of drug-conjugates, usually obtained by covalent coupling of a drug with biocompatible lipid moieties to form nanoparticles, has gained considerable attention. Natural products isolated from plants have been a successful source of potential drug leads with unique structural diversity. In the present work three molecules derived from natural products were employed as lead molecules for the synthesis of self-assembled nanoparticles. The first molecule is the cytotoxic royleanone 7α-acetoxy-6β-hydroxyroyleanone (Roy, 1) that has been isolated from hairy coleus (Plectranthus hadiensis (Forssk.) Schweinf). ex Sprenger leaves in a large amount. This royleanone, its hemisynthetic derivative 7α-acetoxy-6β-hydroxy-12-benzoyloxyroyleanone (12BzRoy, 2) and 6,7-dehydroroyleanone (DHR, 3), isolated from the essential oil of thicket coleus (P. madagascariensis (Pers.) Benth.) were employed in this study. The royleanones were conjugated with squalene (sq), oleic acid (OA), and/or 1-bromododecane (BD) self-assembly inducers. Roy-OA, DHR-sq, and 12BzRoy-sq conjugates were successfully synthesized and characterized. The cytotoxic effect of DHR-sq was previously assessed on three human cell lines: NCI-H460 (IC50 74.0 ± 2.2 µM), NCI-H460/R (IC50 147.3 ± 3.7 µM), and MRC-5 (IC50 127.3 ± 7.3 µM), and in this work Roy-OA NPs was assayed against Vero-E6 cells at different concentrations (0.05, 0.1, and 0.2 mg/mL). The cytotoxicity of DHR-sq NPs was lower when compared with DHR alone in these cell lines: NCI-H460 (IC50 10.3 ± 0.5 µM), NCI-H460/R (IC50 10.6 ± 0.4 µM), and MRC-5 (IC5016.9 ± 0.5 µM). The same results were observed with Roy-OA NPs against Vero-E6 cells as was found to be less cytotoxic than Roy alone in all the concentrations tested. From the obtained DLS results, 12BzRoy-sq assemblies were not in the nano range, although Roy-OA NP assemblies show a promising size (509.33 nm), Pdl (0.249), zeta potential (−46.2 mV), and spherical morphology from SEM. In addition, these NPs had a low release of Roy at physiological pH 7.4 after 24 h. These results suggest the nano assemblies can act as prodrugs for the release of cytotoxic lead molecules.
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Affiliation(s)
- Epole Ntungwe
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- Pharmacology Area (Pharmacognosy Laboratory), New Antitumor Compounds: Toxic Action on Leukemia Cells Research Group, Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcalá de Henares, Ctra. A2, Km 33.100–Campus Universitario, 28805 Alcalá de Henares, Spain;
| | - Eva María Domínguez-Martín
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- Pharmacology Area (Pharmacognosy Laboratory), New Antitumor Compounds: Toxic Action on Leukemia Cells Research Group, Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcalá de Henares, Ctra. A2, Km 33.100–Campus Universitario, 28805 Alcalá de Henares, Spain;
| | - Gabrielle Bangay
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- Pharmacology Area (Pharmacognosy Laboratory), New Antitumor Compounds: Toxic Action on Leukemia Cells Research Group, Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcalá de Henares, Ctra. A2, Km 33.100–Campus Universitario, 28805 Alcalá de Henares, Spain;
| | - Catarina Garcia
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- Pharmacology Area (Pharmacognosy Laboratory), New Antitumor Compounds: Toxic Action on Leukemia Cells Research Group, Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcalá de Henares, Ctra. A2, Km 33.100–Campus Universitario, 28805 Alcalá de Henares, Spain;
| | - Iris Guerreiro
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
| | - Eleonora Colombo
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milano, Italy; (E.C.); (D.P.)
| | - Lucilia Saraiva
- LAQV-Faculty of Pharmacy of University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313 Porto, Portugal;
| | - Ana María Díaz-Lanza
- Pharmacology Area (Pharmacognosy Laboratory), New Antitumor Compounds: Toxic Action on Leukemia Cells Research Group, Department of Biomedical Sciences, Faculty of Pharmacy, University of Alcalá de Henares, Ctra. A2, Km 33.100–Campus Universitario, 28805 Alcalá de Henares, Spain;
| | - Andreia Rosatella
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- iMed.ULisboa, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal;
| | - Marta M. Alves
- Centro de Química Estrutural, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais, 1, 1049-001 Lisboa, Portugal;
| | - Catarina Pinto Reis
- iMed.ULisboa, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal;
| | - Daniele Passarella
- Department of Chemistry, University of Milan, Via Golgi 19, 20133 Milano, Italy; (E.C.); (D.P.)
| | - Patricia Rijo
- CBIOS—Universidade Lusófona’s Research Center for Biosciences & Health Technologies, Campo Grande 376, 1749-024 Lisbon, Portugal; (E.N.); (E.M.D.-M.); (G.B.); (C.G.); (I.G.); (A.R.)
- iMed.ULisboa, Faculdade de Farmácia da Universidade de Lisboa, Av. Prof. Gama Pinto, 1649-003 Lisboa, Portugal;
- Correspondence:
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4
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Wang X, He F, Zhang L, Yu A. Application of micro-nanostructured magnetite in separating tetrabromobisphenol A and hexabromocyclododecane from environmental water by magnetic solid phase extraction. PLoS One 2021; 16:e0251021. [PMID: 33939758 PMCID: PMC8092778 DOI: 10.1371/journal.pone.0251021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2020] [Accepted: 04/19/2021] [Indexed: 11/18/2022] Open
Abstract
Two typical brominated flame retardants (BFRs), namely, tetrabromobisphenol A (TBBPA) and hexabromocyclododecane (HBCD), were persistent organic pollutants widely detected in various environmental media. This study aimed to successfully synthesize micro-nano-structured magnetite particles (MNMPs) with surface modification by citric acid molecules. The synthesized composites served as an adsorbent for extracting TBBPA and HBCD from environmental water samples followed by gas chromatography–mass spectrometry analysis. The obtained MNMPs were characterized in terms of crystal structure, morphology, size distribution, hydrophobic and hydrophilic performance and magnetism. The results indicated that the MNMPs exhibited high surface area, good dispersibility, and strong magnetic responsiveness for separation. The parameters affecting the extraction efficiency were optimized, including sample pH, amount of sorbents, extraction time and desorption conditions. Under the optimum conditions, the recovery was 83.5 and 107.1%, limit of detection was 0.13 and 0.35μg/mL (S/N = 3), and limit of quantification was 0.37 and 0.59 μg/mL (S/N = 10) for TBBPA and HBCD respectively. The relative standard deviations obtained using the proposed method were less than 8.7%, indicating that the MNMP magnetic solid-phase extraction method had advantages of simplicity, good sensitivity and high efficiency for the extraction of the two BFRs from environmental water.
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Affiliation(s)
- Xiaoping Wang
- Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, Jiangsu, China
- Institute of Environmental Risk and Damage, Jiangsu Environmental Engineering Technology Co. LTD, Nanjing, Jiangsu, China
| | - Fengzhi He
- Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, Jiangsu, China
- Institute of Environmental Risk and Damage, Jiangsu Environmental Engineering Technology Co. LTD, Nanjing, Jiangsu, China
| | - Limin Zhang
- Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, Jiangsu, China
- Institute of Environmental Risk and Damage, Jiangsu Environmental Engineering Technology Co. LTD, Nanjing, Jiangsu, China
| | - Ang Yu
- Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing, Jiangsu, China
- Institute of Environmental Risk and Damage, Jiangsu Environmental Engineering Technology Co. LTD, Nanjing, Jiangsu, China
- * E-mail:
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5
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Truong JQ, Nguyen S, Bruning JB, Shearwin KE. Simplified heavy-atom derivatization of protein structures via co-crystallization with the MAD tetragon tetrabromoterephthalic acid. Acta Crystallogr F Struct Biol Commun 2021; 77:156-162. [PMID: 33949976 PMCID: PMC8098126 DOI: 10.1107/s2053230x21004052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 04/15/2021] [Indexed: 11/10/2022] Open
Abstract
The phase problem is a persistent bottleneck that impedes the structure-determination pipeline and must be solved to obtain atomic resolution crystal structures of macromolecules. Although molecular replacement has become the predominant method of solving the phase problem, many scenarios still exist in which experimental phasing is needed. Here, a proof-of-concept study is presented that shows the efficacy of using tetrabromoterephthalic acid (B4C) as an experimental phasing compound. Incorporating B4C into the crystal lattice using co-crystallization, the crystal structure of hen egg-white lysozyme was solved using MAD phasing. The strong anomalous signal generated by its four Br atoms coupled with its compatibility with commonly used crystallization reagents render B4C an effective experimental phasing compound that can be used to overcome the phase problem.
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Affiliation(s)
- Jia Q. Truong
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Stephanie Nguyen
- Institute of Photonics and Advanced Sensing (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - John B. Bruning
- Institute of Photonics and Advanced Sensing (IPAS), School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
| | - Keith E. Shearwin
- School of Biological Sciences, The University of Adelaide, Adelaide, South Australia 5005, Australia
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Khadake SN, Karamathulla S, Jena TK, Monisha M, Tuti NK, Khan FA, Anindya R. Synthesis and antibacterial activities of marine natural product ianthelliformisamines and subereamine synthetic analogues. Bioorg Med Chem Lett 2021; 39:127883. [PMID: 33662536 DOI: 10.1016/j.bmcl.2021.127883] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 02/09/2021] [Accepted: 02/10/2021] [Indexed: 11/19/2022]
Abstract
Marine sponges of the genusSuberea produce variety of brominated tyrosine alkaloids which display diverse range of biological activities including antiproliferative, antimicrobial and antimalarial activities. In continuation of our search for biologically active marine natural products for antibacterial compounds, we report here the synthesis and evaluation of biological activity of panel of ianthelliformisamines and subereamine analogues using the literature known acid-amine coupling reaction. Several derivatives of Ianthelliformisamine were achieved by the coupling of Boc-protected polyamine chain with brominated aromatic acrylic acid derivatives by varying the bromine substituents on aromatic acid derivatives, amine spacer as well as geometry of the double bond, and then Boc-deprotection using TFA. Similarly, subereamine analogues were also synthesized employing coupling reaction between various brominated phenyl acrylic acids with commercially available chiral amino ester derivatives followed by ester hydrolysis. We screened these synthetic analogues for antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) strains. One of the compound 7c showed bactericidal activity against Staphylococcus aureus with an IC50 value of 3.8 μM (MIC = 25 μM).
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Affiliation(s)
- Shivaji Narayan Khadake
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Shaik Karamathulla
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Tapan Kumar Jena
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Mohan Monisha
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Nikhil Kumar Tuti
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Faiz Ahmed Khan
- Department of Chemistry, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India
| | - Roy Anindya
- Department of Biotechnology, Indian Institute of Technology Hyderabad, Kandi, Sangareddy 502285, India.
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Abstract
Presented herein is the discovery that bismuth(iii) trifluoromethanesulfonate (Bi(OTf)3) is an effective catalyst for the activation of glycosyl bromides and glycosyl chlorides. The key objective for the development of this methodology is to employ only one promoter in the lowest possible amount and to avoid using any additive/co-catalyst/acid scavenger except molecular sieves. Bi(OTf)3 works well in promoting the glycosidation of differentially protected glucosyl, galactosyl, and mannosyl halides with many classes of glycosyl acceptors. Most reactions complete within 1 h in the presence of only 35% of green and light-stable Bi(OTf)3 catalyst.
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Affiliation(s)
- Hayley B Steber
- Department of Chemistry and Biochemistry, University of Missouri - St Louis, One University Boulevard, St Louis, Missouri 63121, USA.
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8
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Wang TH, Hsu LW, Chang HC. Structural Reorganization of Imidazolium Ionic Liquids Induced by Pressure-Enhanced Ionic Liquid-Polyethylene Oxide Interactions. Int J Mol Sci 2021; 22:981. [PMID: 33478151 PMCID: PMC7835789 DOI: 10.3390/ijms22020981] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 01/14/2021] [Accepted: 01/16/2021] [Indexed: 01/01/2023] Open
Abstract
Mixtures of polyethylene oxide (PEO, M.W.~900,000) and imidazolium ionic liquids (ILs) are studied using high-pressure Fourier-transform infrared spectroscopy. At ambient pressure, the spectral features in the C-H stretching region reveal that PEO can disturb the local structures of the imidazolium rings of [BMIM]+ and [HMIM]+. The pressure-induced phase transition of pure 1-butyl-3-methylimidazolium bromide ([BMIM]Br) is observed at a pressure of 0.4 GPa. Pressure-enhanced [BMIM]Br-PEO interactions may assist PEO in dividing [BMIM]Br clusters to hinder the aggregation of [BMIM]Br under high pressures. The C-H absorptions of pure 1-hexyl-3-methylimidazolium bromide [HMIM]Br do not show band narrowing under high pressures, as observed for pure [BMIM]Br. The band narrowing of C-H peaks is observed at 1.5 GPa for the [HMIM]Br-PEO mixture containing 80 wt% of [HMIM]Br. The presence of PEO may reorganize [HMIM]Br clusters into a semi-crystalline network under high pressures. The differences in aggregation states for ambient-pressure phase and high-pressure phase may suggest the potential of [HMIM]Br-PEO (M.W.~900,000) for serving as optical or electronic switches.
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Affiliation(s)
| | | | - Hai-Chou Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan; (T.-H.W.); (L.-W.H.)
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9
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Matsumura M, Matsuhashi Y, Kawakubo M, Hyodo T, Murata Y, Kawahata M, Yamaguchi K, Yasuike S. Synthesis, Structural Characterization, and Optical Properties of Benzene-Fused Tetracyclic and Pentacyclic Stiboles. Molecules 2021; 26:molecules26010222. [PMID: 33406769 PMCID: PMC7795936 DOI: 10.3390/molecules26010222] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 12/22/2020] [Accepted: 12/28/2020] [Indexed: 01/16/2023] Open
Abstract
The expectation that antimony (Sb) compounds should display phosphorescence emissions based on the “heavy element effect” prompted our interest in the introduction of antimony to a biaryl as the bridging atom in a fused heterole system. Herein, the synthesis, molecular structures, and optical properties of novel benzene-fused heteroacenes containing antimony or arsenic atoms are described. The stiboles and arsole were prepared by the condensation of dibromo(phenyl)stibane or dichloro(phenyl)arsine with dilithium intermediates derived from the corresponding dibromo compounds. Nuclear magnetic resonance (NMR) spectroscopy and X-ray crystal analysis revealed that the linear pentacyclic stibole was highly symmetric in both the solution and crystal states. In contrast, the curved pentacyclic stibole adopted a helical structure in solution, and surprisingly, only M helical molecules were crystallized from the racemate. All synthesized compounds produced very weak or no emissions at room temperature or in the solid state. In contrast, the linear penta- and tetracyclic stiboles exhibited clear phosphorescence emissions in the CHCl3 frozen matrix at 77 K under aerobic conditions.
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Affiliation(s)
- Mio Matsumura
- School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan; (M.M.); (Y.M.); (M.K.); (Y.M.)
| | - Yuki Matsuhashi
- School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan; (M.M.); (Y.M.); (M.K.); (Y.M.)
| | - Masato Kawakubo
- School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan; (M.M.); (Y.M.); (M.K.); (Y.M.)
| | - Tadashi Hyodo
- Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan; (T.H.); (M.K.); (K.Y.)
| | - Yuki Murata
- School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan; (M.M.); (Y.M.); (M.K.); (Y.M.)
| | - Masatoshi Kawahata
- Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan; (T.H.); (M.K.); (K.Y.)
| | - Kentaro Yamaguchi
- Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, 1314-1 Shido, Sanuki, Kagawa 769-2193, Japan; (T.H.); (M.K.); (K.Y.)
| | - Shuji Yasuike
- School of Pharmaceutical Sciences, Aichi Gakuin University, 1-100 Kusumoto-cho, Chikusa-ku, Nagoya 464-8650, Japan; (M.M.); (Y.M.); (M.K.); (Y.M.)
- Correspondence: ; Tel.: +81-52-757-6774
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10
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Dong H, Dong S, Erik Hansen P, Stagos D, Lin X, Liu M. Progress of Bromophenols in Marine Algae from 2011 to 2020: Structure, Bioactivities, and Applications. Mar Drugs 2020; 18:E411. [PMID: 32759739 PMCID: PMC7459620 DOI: 10.3390/md18080411] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2020] [Revised: 07/24/2020] [Accepted: 07/25/2020] [Indexed: 12/11/2022] Open
Abstract
Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antiradical, antimicrobial, anticancer, antidiabetic, anti-inflammatory effects, and so on. Here, we briefly review the recent progress of these marine algae biomaterials and their derivatives from 2011 to 2020, with respect to structure, bioactivities, and their potential application as pharmaceuticals.
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Affiliation(s)
- Hui Dong
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; (H.D.); (S.D.)
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Songtao Dong
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; (H.D.); (S.D.)
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Poul Erik Hansen
- Department of Science and Environment, Roskilde University, 4000 Roskilde, Denmark;
| | - Dimitrios Stagos
- Department of Biochemistry and Biotechnology, School of Health Sciences, University of Thessaly, Biopolis, 41500 Larissa, Greece;
| | - Xiukun Lin
- Department of Pharmacology, School of Pharmacy, Southwest Medical University, 319 Zhongshan Road, Jiangyang, Luzhou 646000, China;
| | - Ming Liu
- Key Laboratory of Marine Drugs, Ministry of Education of China, School of Medicine and Pharmacy, Ocean University of China, 5 Yushan Road, Qingdao 266003, China; (H.D.); (S.D.)
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
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11
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Tso CP, Kuo DTF, Shih YH. Removal of hexabromocyclododecane by carboxymethyl cellulose stabilized Fe and Ni/Fe bimetallic nanoparticles: The particle stability and reactivity in water. Chemosphere 2020; 250:126155. [PMID: 32105853 DOI: 10.1016/j.chemosphere.2020.126155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 01/26/2020] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
Aggregation of nanoparticles (NPs) can hinder the degradative reactivity of particles towards organic pollutants as it reduces available surface area for reaction. This limitation may be circumvented by applying dispersant to improve colloidal stability of nanoparticle suspension. This study examined the removal of hexabromocyclododecane (HBCD), a recently listed persistent organic pollutant, by carboxymethylcellulose (CMC) stabilized nanoscale zerovalent iron (CMC-NZVI) and bimetallic Ni/Fe nanoparticles (CMC-Ni/Fe) under the influence of suspension chemistry. The mass-normalized removal rate constants of HBCD by CMC-Ni/Fe NPs increased with lower particle aggregation. However, the coating could introduce diffusion resistance as HBCD diffused through the CMC layer to the Fe surface. The activation energy was estimated to be 26.8 kJ mol-1, indicating the overall reaction process was neither surface-limited nor diffusion-controlled. The reactivity of CMC-Ni/Fe NPs toward HBCD was not affected by aqueous initial pH substantially. Common monoanions (Cl-, NO3-, and HCO3-) generally enhanced HBCD adsorption but diminished its debromination. The removal rate did not differ significantly among the studied monoanions over a concentration of 2.5-10 mM except HCO3-. Overall, CMC coating can stabilize Ni/Fe NPs, increase their adsorption of HBCD, provide buffer pH capacity, and overcome common inhibition effects of anions in water. These findings suggested the high potential of using CMC-Ni/Fe NPs for in-situ remediation.
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Affiliation(s)
- Chih-Ping Tso
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Dave Ta Fu Kuo
- Department of Architecture and Civil Engineering, City University of Hong Kong, Hong Kong
| | - Yang-Hsin Shih
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan.
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12
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Deba F, Ramos K, Vannoy M, Munoz K, Akinola LS, Damaj MI, Hamouda AK. Examining the Effects of (α4)3(β2)2 Nicotinic Acetylcholine Receptor-Selective Positive Allosteric Modulator on Acute Thermal Nociception in Rats. Molecules 2020; 25:molecules25122923. [PMID: 32630476 PMCID: PMC7355939 DOI: 10.3390/molecules25122923] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 06/19/2020] [Accepted: 06/22/2020] [Indexed: 12/14/2022] Open
Abstract
Neuronal nicotinic acetylcholine receptor (nAChR)-based therapeutics are sought as a potential alternative strategy to opioids for pain management. In this study, we examine the antinociceptive effects of 3-(2-chlorophenyl)-5-(5-methyl-1-(piperidin-4-yl)-1H-pyrazol-4-yl)isoxazole (CMPI), a novel positive allosteric modulator (PAM), with preferential selectivity to the low agonist sensitivity (α4)3(β2)2 nAChR and desformylflustrabromine (dFBr), a PAM for α4-containing nAChRs. We used hot plate and tail flick tests to measure the effect of dFBr and CMPI on the latency to acute thermal nociceptive responses in rats. Intraperitoneal injection of dFBr, but not CMPI, dose-dependently increased latency in the hot plate test. In the tail flick test, the effect achieved at the highest dFBr or CMPI dose tested was only <20% of the maximum possible effects reported for nicotine and other nicotinic agonists. Moreover, the coadministration of dFBr did not enhance the antinociceptive effect of a low dose of nicotine. Our results show that the direct acute effect of dFBr is superior to that for CMPI, indicating that selectivity to (α4)3(β2)2 nAChR is not advantageous in alleviating responses to acute thermal nociceptive stimulus. However, further studies are necessary to test the suitability of (α4)3(β2)2 nAChR-selective PAMs in chronic pain models.
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Affiliation(s)
- Farah Deba
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Texas at Tyler, Tyler, TX 75799, USA;
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center MS 131, 1010 W. Ave. B, Kingsville, TX 78363, USA; (K.R.); (M.V.); (K.M.)
| | - Kara Ramos
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center MS 131, 1010 W. Ave. B, Kingsville, TX 78363, USA; (K.R.); (M.V.); (K.M.)
| | - Matthew Vannoy
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center MS 131, 1010 W. Ave. B, Kingsville, TX 78363, USA; (K.R.); (M.V.); (K.M.)
| | - Kemburli Munoz
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center MS 131, 1010 W. Ave. B, Kingsville, TX 78363, USA; (K.R.); (M.V.); (K.M.)
| | - Lois S. Akinola
- Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Kontos Medical Science Building, 1217 E. Marshall St., P.O. Box 980613, Richmond, VA 23298, USA; (L.S.A.); (M.I.D.)
| | - M. Imad Damaj
- Department of Pharmacology and Toxicology, Medical College of Virginia, Virginia Commonwealth University, Kontos Medical Science Building, 1217 E. Marshall St., P.O. Box 980613, Richmond, VA 23298, USA; (L.S.A.); (M.I.D.)
| | - Ayman K. Hamouda
- Department of Pharmaceutical Sciences, College of Pharmacy, The University of Texas at Tyler, Tyler, TX 75799, USA;
- Department of Pharmaceutical Sciences, College of Pharmacy, Texas A&M Health Sciences Center MS 131, 1010 W. Ave. B, Kingsville, TX 78363, USA; (K.R.); (M.V.); (K.M.)
- Correspondence: ; Tel.: +1-903-565-6578
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13
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Chang TH, Wang R, Peng YH, Chou TH, Li YJ, Shih YH. Biodegradation of hexabromocyclododecane by Rhodopseudomonas palustris YSC3 strain: A free-living nitrogen-fixing bacterium isolated in Taiwan. Chemosphere 2020; 246:125621. [PMID: 31896015 DOI: 10.1016/j.chemosphere.2019.125621] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2019] [Revised: 11/23/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
The persistent organic pollutant, brominated flame retardant, hexabromocyclododecane (HBCD), identified as an emerging contaminant has been detected in various environmental matrix. The increased level of this toxic organic compound in the environment has been associated with serious human health risks. The results obtained from this study revealed that various Rhodopseudomonas palustris strains isolated from paddy soil in Taiwan possessed good HBCD biodegradation capability when they were cultured aerobically. Among these strains, YSC3 was considered as one of the most potential isolates for HBCD degradation. The optimum HBCD biodegradation occurred at neutral pH and at 35 °C in all our pH and temperature tests at an initial HBCD concentration of 1 ppm. HBCD degradation kinetics generally decreased with the increase of initial HBCD concentration. The study also suggested that the cultivation temperature played a vital role on YSC3 for its initiation of cellular HBCD degradation. The relative-molar ratio of the released bromide ions during the biodegradation of HBCD was observed in the range between 1 and 3.5, suggesting that the debromination reactions occurred. Concomitant with the loss of HBCD, there was a concurrent production of two metabolites, pentabromocyclododecanol and pentabromocyclododecene, which were determined by liquid chromatography and mass spectrometry techniques. On the basis of the obtained results, the possible biodegradation pathways were also proposed in this study.
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Affiliation(s)
- Tse-Hao Chang
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Reuben Wang
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan; Department of Food Science, Tunghai University, No. 1727, Sec. 4 Taiwan Boulevard, Xitun District, Taichung, 40704, Taiwan
| | - Yu-Huei Peng
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Tzu-Ho Chou
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Yi-Jie Li
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan
| | - Yang-Hsin Shih
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei, 106, Taiwan.
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14
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Zhang X, Roopnarine KK, Dong S, Jans U. Stereoisomer specific reaction of hexabromocyclododecane with Fe(ii) associated with iron oxides. Environ Sci Process Impacts 2020; 22:1026-1036. [PMID: 32118215 DOI: 10.1039/c9em00587k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The reactions of hexabromocyclododecane (HBCD) isomers with Fe(ii) associated with iron oxides were performed in a pH range from 6.15 to 7.50 at room temperature. It was observed that Fe(ii) associated with iron oxides (i.e., goethite, magnetite, hematite) is a better reductant than just an aqueous solution of Fe(ii) to potentially reduce HBCD in subsurface environments. The reaction of HBCD with Fe(ii) associated with iron oxides is also stereoisomer specific with α-HBCD reacting much slower than β-HBCD and γ-HBCD. The reaction is pH dependent and it is faster with increased pH. The initial concentration of Fe(ii) and HBCD can also affect the reaction rate. The reaction is negligible when all the Fe(ii) is sorbed to magnetite and no Fe(ii) remains dissolved. It was also observed that the reaction of 100 nM HBCD is slower than the reaction of 1.0 μM HBCD with Fe(ii) associated with magnetite. In addition, natural organic matter (NOM) was found to inhibit the degradation of HBCD by Fe(ii) associated with iron oxides.
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Affiliation(s)
- Xianmiao Zhang
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY 10016, USA
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15
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Jiang Y, Yang S, Liu J, Ren T, Zhang Y, Sun X. Degradation of hexabromocyclododecane (HBCD) by nanoscale zero-valent aluminum (nZVAl). Chemosphere 2020; 244:125536. [PMID: 31816547 DOI: 10.1016/j.chemosphere.2019.125536] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 12/01/2019] [Accepted: 12/02/2019] [Indexed: 06/10/2023]
Abstract
Hexabromocyclododecane (HBCD) has been listed in Annex A of the Stockholm Convention on Persistent Organic Pollutants (POPs) in 2013, but till now there is a lack of efficient methods for its degradation. In this study, nanoscale zero-valent aluminum (nZVAl), an excellent reductant with a very low redox potential of E0(Al3+/Al0) = -1.662 V and strong electron transfer ability, was used to reductively degrade HBCD. Nearly 100% HBCD was degraded within 8 h reaction at 25 °C in ethanol/water (v/v, 50/50) solution without pH adjustment. And about 67% cyclododecatriene (CDT) was obtained, which is the complete debromination product. What's more, the yield of Br- could achieve nearly 100% after optimizing conditions. The reaction was strongly promoted by increasing the dosages of nZVAl or decreasing the initial concentration of HBCD. The temperature had the most significant influence and the degradation was completed in 40 min with elevating the reaction temperature to 45 °C. The reaction mechanism was further revealed through the characterization of nZVAl particles before and after the reaction by SEM-EDS, TEM, HRTEM, XRD, and XPS. It was found that, after corrosion of the oxide film on the surface of nZVAl, metallic aluminum inside was exposed. The reactive sites were provided and electrons released were transferred from nZVAl to HBCD, causing HBCD degraded to dibromocyclododecadiene (DBCD) and then CDT by reductive debromination. These findings imply that nZVAl can degrade HBCD efficiently with no extra energy input and this offers a new idea for better treatment of HBCD.
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Affiliation(s)
- Yuting Jiang
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Shiying Yang
- Key Laboratory of Marine Environment and Ecology, Ministry of Education, Qingdao, 266100, China; Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering (MEGE), Qingdao, 266100, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
| | - Junqin Liu
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Tengfei Ren
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Yixuan Zhang
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Xinrong Sun
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
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16
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Liu H, Tong T, Pu Y, Sun B, Zhu X, Yan Z. Insight Into the Formation Paths of Methyl Bromide From Syringic Acid in Aqueous Bromide Solutions Under Simulated Sunlight Irradiation. Int J Environ Res Public Health 2020; 17:ijerph17062081. [PMID: 32245114 PMCID: PMC7142905 DOI: 10.3390/ijerph17062081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 03/08/2020] [Accepted: 03/18/2020] [Indexed: 11/29/2022]
Abstract
Methyl bromide (CH3Br) is one of the largest natural sources of bromine in the stratosphere, where it leads to ozone depletion. This paper reported the photochemical production of CH3Br from syringic acid (SA) that has been used as an environmentally relevant model compound for terrestrially-derived dissolved organic matter. The formation of CH3Br increased with the increase of bromide ion concentration ranging from 0.8 to 80 mmol L−1. Ferric ions (Fe(III)) enhanced CH3Br production, while chloride inhibited it, with or without Fe(III). Meanwhile, methyl chloride (CH3Cl) was generated in the presence of chloride and was inhibited by Fe(III). The different effects of Fe(III) on the formation of CH3Cl and CH3Br indicate their diverse formation paths. Based on the intermediates identified by liquid chromatography-mass spectrometry and the confirmation of the formation of Fe(III)-SA complexes, it was proposed that there were two formation paths of CH3Br from SA in the bromide-enriched water under simulated sunlight irradiation. One path was via nucleophilic attack of Br− on the excited state protonation of SA; the other was via the combination of methyl radical and bromine radical when Fe(III) was present. This work suggests that the photochemical formation of CH3Br may act as a potential natural source of CH3Br in the bromide-enriched environmental matrix, and helps in better understanding the formation mechanism of CH3Br.
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17
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Liu H, Tong T, Pu Y, Zhu X, Sun B, Wang Z, Yan Z. Methyl bromide production from dissolved organic matter under simulated sunlight irradiation and the important effect of ferric ions. Environ Sci Process Impacts 2020; 22:751-758. [PMID: 32067016 DOI: 10.1039/c9em00473d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The oceans play an important role in the biogeochemical cycle of methyl bromide (CH3Br), as not only the sinks but also the sources. However, many uncertainties exist regarding the way of CH3Br generation in the marine environment. To illustrate the possibility of photochemical formation of CH3Br in saline water, its generation in bromide aqueous solution containing humic acid (HA) and ferric ions (Fe(iii)) was investigated. CH3Br was obviously generated after irradiation, and its amounts increased with increasing HA concentration from 0.82 to 12.2 mgC L-1. Fe(iii) significantly promoted CH3Br production, and the described production process in the presence of Fe(iii) was pH-dependent, decreasing with the increase of pH. Finally, the concentrations of CH3Br in natural coastal seawater and seawater with HA were measured, and the results showed that CH3Br was significantly generated under irradiation. Our results suggest that the photochemical process of dissolved organic matter may be one source of CH3Br in the marine environment.
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Affiliation(s)
- Hui Liu
- College of Environmental Science and Engineering, Dalian Maritime University, Dalian 116026, China.
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18
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St-Pierre J, Zhai Y. Impact of the Cathode Pt Loading on PEMFC Contamination by Several Airborne Contaminants. Molecules 2020; 25:molecules25051060. [PMID: 32120973 PMCID: PMC7179096 DOI: 10.3390/molecules25051060] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 02/21/2020] [Accepted: 02/23/2020] [Indexed: 11/29/2022] Open
Abstract
Proton exchange membrane fuel cells (PEMFCs) with 0.1 and 0.4 mg Pt cm−2 cathode catalyst loadings were separately contaminated with seven organic species: Acetonitrile, acetylene, bromomethane, iso-propanol, methyl methacrylate, naphthalene, and propene. The lower catalyst loading led to larger cell voltage losses at the steady state. Three closely related electrical equivalent circuits were used to fit impedance spectra obtained before, during, and after contamination, which revealed that the cell voltage loss was due to higher kinetic and mass transfer resistances. A significant correlation was not found between the steady-state cell voltage loss and the sum of the kinetic and mass transfer resistance changes. Major increases in research program costs and efforts would be required to find a predictive correlation, which suggests a focus on contamination prevention and recovery measures rather than contamination mechanisms.
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Liu Y, Luo X, Zeng Y, Deng M, Tu W, Wu Y, Mai B. Bioaccumulation and biomagnification of hexabromocyclododecane (HBCDD) in insect-dominated food webs from a former e-waste recycling site in South China. Chemosphere 2020; 240:124813. [PMID: 31542576 DOI: 10.1016/j.chemosphere.2019.124813] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 09/06/2019] [Accepted: 09/06/2019] [Indexed: 06/10/2023]
Abstract
Hexabromocyclododecane (HBCDD) has frequently been detected in wildlife. However, there is limited research on its bioaccumulation and biomagnification in insect-dominated aquatic and terrestrial food webs. This study investigated the occurrence of HBCDD in insects and their predators collected from a former e-waste contaminated pond and its surrounding region. The concentrations of ƩHBCDD (sum concentrations of α-, β-, and γ-HBCDDs) ranged from nd to 179 ng g-1 lipid weight. α-HBCDD was the predominant diastereoisomer in all biotic samples, and the contribution of α-HBCDD was higher in predators than in prey insects. A significantly positive linear relationship was found between ƩHBCDD concentrations (lipid weight) and trophic levels based on δ15N in aquatic organisms (p < 0.05), while trophic dilution was observed in the terrestrial food web. This result indicates an opposite trophic transfer tendency of HBCDD in terrestrial and aquatic ecosystems. The biomagnification factor (BMF) for α-HBCDD was higher in terrestrial birds (2.03) than in frogs (0.29), toads (0.85), and lizards (0.63). This may be due to differences between poikilotherms and homeotherms in terrestrial ecosystems.
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Affiliation(s)
- Yu Liu
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China; Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang, 330012, PR China
| | - Xiaojun Luo
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China.
| | - Yanghong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China
| | - Mi Deng
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang, 330012, PR China
| | - Wenqing Tu
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang, 330012, PR China
| | - Yongming Wu
- Research Institute of Poyang Lake, Jiangxi Academy of Sciences, Nanchang, 330012, PR China.
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, PR China
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20
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Hofer S, Hartmann A, Orfanoudaki M, Nguyen Ngoc H, Nagl M, Karsten U, Heesch S, Ganzera M. Development and Validation of an HPLC Method for the Quantitative Analysis of Bromophenolic Compounds in the Red Alga Vertebrata lanosa. Mar Drugs 2019; 17:md17120675. [PMID: 31795441 PMCID: PMC6950000 DOI: 10.3390/md17120675] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 10/27/2019] [Indexed: 12/25/2022] Open
Abstract
Bromophenols are a class of compounds occurring in red algae that are thought to play a role in chemical protection; however, their exact function is still not fully known. In order to investigate their occurrence, pure standards of seven bromophenols were isolated from a methanolic extract of the epiphytic red alga Vertebrata lanosa collected in Brittany, France. The structures of all compounds were determined by NMR and MS. Among the isolated substances, one new natural product, namely, 2-amino-5-(3-(2,3-dibromo-4,5-dihydroxybenzyl)ureido)pentanoic acid was identified. An HPLC method for the separation of all isolated substances was developed using a Phenomenex C8(2) Luna column and a mobile phase comprising 0.05% trifluoroacetic acid in water and acetonitrile. Method validation showed that the applied procedure is selective, linear (R2 ≥ 0.999), precise (intra-day ≤ 6.28%, inter-day ≤ 5.21%), and accurate (with maximum displacement values of 4.93% for the high spikes, 4.80% for the medium spikes, and 4.30% for the low spikes). For all standards limits of detection (LOD) were lower than 0.04 μg/mL and limits of quantification (LOQ) lower than 0.12 μg/mL. Subsequently, the method was applied to determine the bromophenol content in Vertebrata lanosa samples from varying sampling sites and collection years showing values between 0.678 and 0.005 mg/g dry weight for different bromophenols with significant variations between the sampling years. Bioactivity of seven isolated bromophenols was tested in agar diffusion tests against Staphylococcus aureus and Escherichia coli bacteria. Three compounds showed a small zone of inhibition against both test organisms at a concentration of 100 µg/mL.
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Affiliation(s)
- Stefanie Hofer
- Department of Pharmacognosy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (S.H.); (M.O.); (M.G.)
| | - Anja Hartmann
- Department of Pharmacognosy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (S.H.); (M.O.); (M.G.)
- Correspondence:
| | - Maria Orfanoudaki
- Department of Pharmacognosy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (S.H.); (M.O.); (M.G.)
| | - Hieu Nguyen Ngoc
- Department of Pharmacognosy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (S.H.); (M.O.); (M.G.)
| | - Markus Nagl
- Institute of Hygiene and Medical Microbiology, Medical University of Innsbruck, Schöpfstraße 41, 6020 Innsbruck, Austria;
| | - Ulf Karsten
- Institute of Biological Sciences, Applied Ecology & Phycology, University of Rostock, Albert-Einstein-Str. 3, 18059 Rostock, Germany; (U.K.); (S.H.)
| | - Svenja Heesch
- Institute of Biological Sciences, Applied Ecology & Phycology, University of Rostock, Albert-Einstein-Str. 3, 18059 Rostock, Germany; (U.K.); (S.H.)
| | - Markus Ganzera
- Department of Pharmacognosy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (S.H.); (M.O.); (M.G.)
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21
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Jeon JW, Kim CS, Kim L, Lee SE, Kim HJ, Lee CH, Choi SD. Distribution and diastereoisomeric profiles of hexabromocyclododecanes in air, water, soil, and sediment samples in South Korea: Application of an optimized analytical method. Ecotoxicol Environ Saf 2019; 181:321-329. [PMID: 31202932 DOI: 10.1016/j.ecoenv.2019.06.015] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 06/03/2019] [Accepted: 06/05/2019] [Indexed: 06/09/2023]
Abstract
In this study, the levels and distribution patterns of HBCD diastereoisomers in air, water, soil, and sediment samples in South Korea were investigated after optimizing the UPLC-MS/MS analytical process. Extraction and cleanup efficiencies were tested using several different extraction solvents and adsorbents. Dichloromethane was selected as the base extraction solvent, and multi-layer silica gel (MSG) and MSG-alumina columns were selected for the removal of HBCDs from complex environmental matrices. The concentration of Ʃ3 HBCDs was 22-133 pg/m3, 10-128 ng/g, 0.2-151 ng/L, and 0.5-552 ng/g dw for air, soil, water, and sediment samples, respectively. Relatively higher concentrations of Ʃ3 HBCDs were observed at stations adjacent to industrial facilities (e.g., rubber and plastic, textile, chemical, fabricated metal, and wholesale trade factories) associated with the use of commercial HBCDs. The proportion of γ-HBCD in the soil (48.3-86.2%) and sediment (54.2-78.1%, except for one station) samples was similar to that found in technical and commercial HBCDs. In contrast, α-HBCD (52.3-71.2%) was dominant in all air samples, while the water samples displayed no clear trend in their diastereoisomer profiles. As the first nationwide report on HBCD diastereoisomers in the environment, this study demonstrates that most environmental compartments in South Korea are moderately contaminated with HBCDs.
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Affiliation(s)
- Jin-Woo Jeon
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - Chul-Su Kim
- UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea
| | - Leesun Kim
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; School of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Sung-Eun Lee
- School of Applied Biosciences, Kyungpook National University, Daegu, 41566, Republic of Korea
| | - Ho-Joong Kim
- Department of Chemicals Management, Korea Environment Corporation (K-eco), Incheon, 22689, Republic of Korea; Department of Environmental Engineering, Inha University, Incheon, 22212, Republic of Korea
| | - Chang-Ho Lee
- Department of Chemicals Management, Korea Environment Corporation (K-eco), Incheon, 22689, Republic of Korea
| | - Sung-Deuk Choi
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea.
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22
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Kovalchuk V, Voronkina A, Binnewerg B, Schubert M, Muzychka L, Wysokowski M, Tsurkan MV, Bechmann N, Petrenko I, Fursov A, Martinovic R, Ivanenko VN, Fromont J, Smolii OB, Joseph Y, Giovine M, Erpenbeck D, Gelinsky M, Springer A, Guan K, Bornstein SR, Ehrlich H. Naturally Drug-Loaded Chitin: Isolation and Applications. Mar Drugs 2019; 17:E574. [PMID: 31658704 PMCID: PMC6835269 DOI: 10.3390/md17100574] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 10/05/2019] [Accepted: 10/08/2019] [Indexed: 12/15/2022] Open
Abstract
Naturally occurring three-dimensional (3D) biopolymer-based matrices that can be used in different biomedical applications are sustainable alternatives to various artificial 3D materials. For this purpose, chitin-based structures from marine sponges are very promising substitutes. Marine sponges from the order Verongiida (class Demospongiae) are typical examples of demosponges with well-developed chitinous skeletons. In particular, species belonging to the family Ianthellidae possess chitinous, flat, fan-like fibrous skeletons with a unique, microporous 3D architecture that makes them particularly interesting for applications. In this work, we focus our attention on the demosponge Ianthella flabelliformis (Linnaeus, 1759) for simultaneous extraction of both naturally occurring ("ready-to-use") chitin scaffolds, and biologically active bromotyrosines which are recognized as potential antibiotic, antitumor, and marine antifouling substances. We show that selected bromotyrosines are located within pigmental cells which, however, are localized within chitinous skeletal fibers of I. flabelliformis. A two-step reaction provides two products: treatment with methanol extracts the bromotyrosine compounds bastadin 25 and araplysillin-I N20 sulfamate, and a subsequent treatment with acetic acid and sodium hydroxide exposes the 3D chitinous scaffold. This scaffold is a mesh-like structure, which retains its capillary network, and its use as a potential drug delivery biomaterial was examined for the first time. The results demonstrate that sponge-derived chitin scaffolds, impregnated with decamethoxine, effectively inhibit growth of the human pathogen Staphylococcus aureus in an agar diffusion assay.
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Affiliation(s)
- Valentine Kovalchuk
- Department of Microbiology, National Pirogov Memorial Medical University, Vinnytsia 21018, Ukraine.
| | - Alona Voronkina
- Department of Pharmacy, National Pirogov Memorial Medical University, Vinnytsia 21018, Ukraine.
| | - Björn Binnewerg
- Institute of Pharmacology and Toxicology, TU Dresden, Dresden 01307, Germany.
| | - Mario Schubert
- Institute of Pharmacology and Toxicology, TU Dresden, Dresden 01307, Germany.
| | - Liubov Muzychka
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Science of Ukraine, Murmanska Str. 1, Kyiv 02094, Ukraine.
| | - Marcin Wysokowski
- Institute of Chemical Technology and Engineering, Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, Poznan 60965, Poland.
- Institute of Electronic and Sensor Materials, TU Bergakademie Freiberg, Gustav-Zeuner Str. 3, Freiberg 09599, Germany.
| | - Mikhail V Tsurkan
- Leibniz Institute for Polymer Research Dresden, Dresden 01069, Germany.
| | - Nicole Bechmann
- Institute of Clinical Chemistry and Laboratory Medicine, University Hospital Carl Gustav Carus, Faculty of Medicine Carl Gustav Carus, TU Dresden, Dresden 01307, Germany.
| | - Iaroslav Petrenko
- Institute of Electronic and Sensor Materials, TU Bergakademie Freiberg, Gustav-Zeuner Str. 3, Freiberg 09599, Germany.
| | - Andriy Fursov
- Institute of Electronic and Sensor Materials, TU Bergakademie Freiberg, Gustav-Zeuner Str. 3, Freiberg 09599, Germany.
| | - Rajko Martinovic
- Institute of Marine Biology, University of Montenegro, Kotor 85330, Montenegro.
| | - Viatcheslav N Ivanenko
- Department of Invertebrate Zoology, Biological Faculty, Lomonosov Moscow State University, Moscow 119992, Russia.
| | - Jane Fromont
- Aquatic Zoology Department, Western Australian Museum, Locked Bag 49, Welshpool DC, Western Australia WA6986, Australia.
| | - Oleg B Smolii
- V.P. Kukhar Institute of Bioorganic Chemistry and Petrochemistry, National Academy of Science of Ukraine, Murmanska Str. 1, Kyiv 02094, Ukraine.
| | - Yvonne Joseph
- Institute of Electronic and Sensor Materials, TU Bergakademie Freiberg, Gustav-Zeuner Str. 3, Freiberg 09599, Germany.
| | - Marco Giovine
- Department of Sciences of Earth, Environment and Life, University of Genoa, Corso Europa 26, 16132 Genova, Italy.
| | - Dirk Erpenbeck
- Department of Earth and Environmental Sciences & GeoBio-Center, Ludwig-Maximilians-Universität München, Richard-Wagner-Str. 10, Munich 80333, Germany.
| | - Michael Gelinsky
- Centre for Translational Bone, Joint and Soft Tissue Research, Faculty of Medicine and University Hospital Carl Gustav Carus of Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
| | - Armin Springer
- Centre for Translational Bone, Joint and Soft Tissue Research, Faculty of Medicine and University Hospital Carl Gustav Carus of Technische Universität Dresden, Fetscherstraße 74, Dresden 01307, Germany.
- Medizinische Biologie und Elektronenmikroskopisches Zentrum (EMZ), Universitätsmedizin Rostock, Rostock 18055, Germany.
| | - Kaomei Guan
- Institute of Pharmacology and Toxicology, TU Dresden, Dresden 01307, Germany.
| | - Stefan R Bornstein
- Department of Internal Medicine III, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden 01307, Germany.
- Diabetes and Nutritional Sciences Division, King's College London, London WC2R 2LS, UK.
| | - Hermann Ehrlich
- Institute of Electronic and Sensor Materials, TU Bergakademie Freiberg, Gustav-Zeuner Str. 3, Freiberg 09599, Germany.
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23
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Gounden AN, Jonnalagadda SB. Advances in Treatment of Brominated Hydrocarbons by Heterogeneous Catalytic Ozonation and Bromate Minimization. Molecules 2019; 24:molecules24193450. [PMID: 31547554 PMCID: PMC6803844 DOI: 10.3390/molecules24193450] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 09/13/2019] [Accepted: 09/19/2019] [Indexed: 11/16/2022] Open
Abstract
The formation of carcinogenic bromate ions is a constraint when ozone is used for the remediation of water containing brominated organic materials. With its strong oxidizing ability, ozone rapidly transforms bromide in aqueous media to bromate, through a series of reactions involving hydroxyl radicals. Several strategies, such as limiting the ozone concentration, maintaining pH < 6, or the use of ammonia or hydrogen peroxide were explored to minimize bromate generation. However, most of the above strategies had a negative effect on the ozonation efficiency. The advanced oxidation processes, using catalysts together with ozone, have proven to be a promising technology for the degradation of pollutants in wastewater, but very few studies have been conducted to find ways to minimize bromate formation during this approach. The proposed article, therefore, presents a comprehensive review on recent advances in bromate reduction in water by catalytic ozonation and proposes reaction mechanisms associated with the catalytic process. The main aim is to highlight any gaps in the reported studies, thus creating a platform for future research and a quest to find environment friendly and efficacious catalysts for minimizing bromate formation in aqueous media during ozonation of brominated organic compounds.
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Affiliation(s)
- Asogan N Gounden
- Department of Chemistry, Mangosuthu University of Technology, P.O. Box 12363, Jacobs 4026, South Africa.
| | - Sreekantha B Jonnalagadda
- School of Chemistry, Westville Campus, University of KwaZulu-Natal, P Bag X54001, Durban 4000, South Africa.
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24
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Wang K, Huang X, Lin K. Multiple catalytic roles of chloroperoxidase in the transformation of phenol: Products and pathways. Ecotoxicol Environ Saf 2019; 179:96-103. [PMID: 31026755 DOI: 10.1016/j.ecoenv.2019.04.061] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Revised: 04/15/2019] [Accepted: 04/19/2019] [Indexed: 06/09/2023]
Abstract
Chloroperoxidase (CPO) is a hybrid of two different families of enzymes, peroxidases and P450s. However, it is poorly understood on CPO's multiple catalytic functions. Herein, phenol was selected as a model substrate to investigate the multiple catalytic roles of CPO. Results showed that phenol was readily transformed into a variety of brominated organic compounds (BOCs) via the CPO-mediated oxidative process. A total of 16 BOCs were identified using gas and liquid chromatography coupled with mass spectrometry. Possible reaction pathways could be attributable to four CPO-mediated processes, including bromination, radical coupling, intramolecular cyclization and debromination. Higher bromide concentrations and lower pH conditions both facilitated the formation of brominated products. While a higher bromination capacity was observed in pH 3.0 solutions, CPO-mediated radical couplings were more favorable at pH 5.0 and 6.0. Although CPO might catalyze chlorination when chloride and bromide coexisted in the solution, BOCs were the dominant products of CPO-mediated phenol oxidation. Results of this study suggest that various catalytic roles of CPO may contribute to the biotic formation of BOCs in the natural environment.
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Affiliation(s)
- Kun Wang
- The Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Center for Marine Environmental Chemistry and Toxicology, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China
| | - Xinwen Huang
- College of Environment, Zhejiang University of Technology, Hangzhou, 310032, China
| | - Kunde Lin
- The Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, Center for Marine Environmental Chemistry and Toxicology, College of the Environment and Ecology, Xiamen University, Xiamen, 361102, China.
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25
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Lörchner D, Kraus W, Köppen R. Photodegradation of the novel brominated flame retardant 2,4,6-Tris-(2,4,6-tribromophenoxy)-1,3,5-triazine in solvent system: Kinetics, photolysis products and pathway. Chemosphere 2019; 229:77-85. [PMID: 31075705 DOI: 10.1016/j.chemosphere.2019.04.184] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 06/09/2023]
Abstract
In this study the direct and indirect photolysis of the novel brominated flame retardant 2,4,6-Tris-(2,4,6-tribromophenoxy)-1,3,5-triazine (TTBP-TAZ) in an organic solvent mixture (60:30:10, ACN:MeOH:THF) under UV-(C) and simulated sunlight irradiation was investigated, and the formed photo-transformation products were identified for the first time. TTBP-TAZ was almost completely degraded within 10 min under UV-(C) irradiation. Due to the fast degradation no specific kinetic order could be observed. In comparison, the reaction under simulated sunlight irradiation was much slower and thus, the kinetic first-order could be determined. The observed photolysis rate constant k as well as the half-life time t1/2 were estimated to be k = (0.0163 ± 0.0002) h-1 and t1/2 = 42.3 h, respectively. The addition of 2-propanol and hydrogen peroxide to investigate the influence of indirect photolysis under UV-(C) irradiation causes no influence on the degradation of TTBP-TAZ. Nevertheless, the removal of TTBP-TAZ under UV-(C) and simulated sunlight without additional chemicals (except solvent) indicates that the direct photolysis plays a significant role in the degradation mechanism of TTBP-TAZ. In both irradiation experiments, TTBP-TAZ was quantitatively degraded that involve the formation of previously unknown PTPs. Overall, two main PTPs were determined when irradiated with UV-(C) and eight sequential debromination products were observed when irradiated by simulated sunlight. These were determined by HPLC-DAD and - MS/(MS), respectively. Based on the chosen experimental conditions the consecutive debromination as well as photo-Fries rearrangement was confirmed as the main degradation pathway by high resolution mass spectrometry and X-ray diffraction.
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Affiliation(s)
- Dominique Lörchner
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Str. 11, D-12489, Berlin, Germany; TU Berlin, Institut für Lebensmitteltechnologie und Lebensmittelchemie, Gustav-Meyer-Allee 25, D-13305, Berlin, Germany
| | - Werner Kraus
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Str. 11, D-12489, Berlin, Germany
| | - Robert Köppen
- Bundesanstalt für Materialforschung und -prüfung (BAM), Richard-Willstätter-Str. 11, D-12489, Berlin, Germany.
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26
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Zhang X, Wilson JH, Lawson AJ, Hohenstein EG, Jans U. Stereoisomer specific reaction of hexabromocyclododecane with reduced sulfur species in aqueous solutions. Chemosphere 2019; 226:238-245. [PMID: 30928716 DOI: 10.1016/j.chemosphere.2019.03.134] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 06/09/2023]
Abstract
The individual degradation rates of the three dominant stereoisomers (α, β, γ) of hexabromocyclododecane (HBCDD) with bisulfide and polysulfides were investigated at pH 9 in methanol/water solutions at two different temperatures (25 °C and 40 °C). Under all conditions investigated, α-HBCDD reacts 10 to 20 times slower with bisulfide than β-HBCDD and γ-HBCDD. The difference in reactivity of HBCDD isomers can be explained by the different populations of stable conformers with large dihedral angle between the vicinal bromine atoms. It was also observed that the reaction of HBCDD with polysulfides is about six times faster than with bisulfide. The experiments performed in solvent mixtures with increased water content at 40 °C indicated that the reaction of HBCDD with bisulfide is faster with higher percentage of water. The much slower abiotic reaction of α-HBCDD compared to β-HBCDD and γ-HBCDD could potentially contribute to the fact that α-HBCDD is more persistent in the environment than γ-HBCDD. Only one isomer of tetrabromocyclododecene (TBCDe-5) was identified as a degradation product of the reaction of HBCDD with reduced sulfur species. TBCDe-5 itself reacts about ten times slower with bisulfide and twenty times slower with polysulfide than HBCDD. The study demonstrates that polysulfides and bisulfides can reduce HBCDD sufficiently in natural anoxic environments and the dominant pathway for the degradation of HBCDD by reduced sulfur species is very likely to be the reductive debromination of vicinal dibromides via concerted anti-elimination.
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Affiliation(s)
- Xianmiao Zhang
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States
| | - John H Wilson
- Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Ariel J Lawson
- Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Edward G Hohenstein
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States; Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States
| | - Urs Jans
- Chemistry Program, The Graduate Center of the City University of New York, New York, NY, 10016, United States; Department of Chemistry and Biochemistry, The City College of New York, CUNY, New York, NY, 10031, United States.
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27
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Heeb NV, Schalles S, Lehner S, Schinkel L, Schilling I, Lienemann P, Bogdal C, Kohler HPE. Biotransformation of short-chain chlorinated paraffins (SCCPs) with LinA2: A HCH and HBCD converting bacterial dehydrohalogenase. Chemosphere 2019; 226:744-754. [PMID: 30965245 DOI: 10.1016/j.chemosphere.2019.03.169] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 03/19/2019] [Accepted: 03/24/2019] [Indexed: 06/09/2023]
Abstract
Short-chain chlorinated paraffins (SCCPs) are polyhalogenated hydrocarbons as are hexachlorocyclohexanes (HCHs) and hexabromocyclododecanes (HBCDs). They all have been classified as persistent organic pollutants (POPs) under the UN Stockholm Convention. Per se such compounds are transformed slowly in the environment, transported over long distances and accumulate in biota. Several Sphingomonadacea strains isolated from HCH dump sites have evolved to express enzymes that can transform HCHs and HBCDs. We hypothesized that LinA2, a dehydrohalogenase expressed in such bacteria, may also transform CPs to chlorinated olefins (COs). Three mixtures of penta- to deca-chlorinated undecanes (C11), dodecanes (C12) and tridecanes (C13) were exposed to LinA2. High-resolution full-scan mass spectra (R∼8'000) of CPs and COs were obtained applying a soft ionization method, enhancing chloride-adduct [M+Cl]- formation. A mathematical deconvolution procedure was used to separate interfering spectra to verify that LinA2 indeed catalyzed the conversion of CPs to COs. About 20-40% of the material was transformed in 24 h, about 50-70% was converted in 200 h. A bimodal first-order kinetic model could describe transformations of reactive and persistent CPs. Under the given conditions reactive CPs (τ1/2 = 1.4-6.9 h) were converted 30 to 190-times faster than the persistent ones (τ1/2 = 150-260 h). Proportions of persistent isomers (pp) varied from 60 to 80%. Lower chlorinated homologues contained higher proportions of persistent isomers. In conclusion, SCCP mixtures contain both, material that is readily converted by LinA2, and persistent material that is not or only slowly transformed.
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Affiliation(s)
- Norbert V Heeb
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland.
| | - Simone Schalles
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland; RWTH, Aachen University, Institute for Environmental Sciences, Worringerweg 1, D-52074, Aachen, Germany; ETH, Swiss Federal Institute of Technology, Institute of Biogeochemistry and Pollutant Dynamic, Universitätsstrasse 16, CH-8092, Zurich, Switzerland
| | - Sandro Lehner
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland; ZHAW, Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Reidbach, CH-8820, Wädenswil, Switzerland
| | - Lena Schinkel
- Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland; ETH, Swiss Federal Institute of Technology, Institute of Chemical and Bioengineering, Vladimir-Prelog-Weg 1, CH-8093, Zurich, Switzerland
| | - Iris Schilling
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600, Dübendorf, Switzerland
| | - Peter Lienemann
- ZHAW, Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Reidbach, CH-8820, Wädenswil, Switzerland
| | - Christian Bogdal
- ETH, Swiss Federal Institute of Technology, Institute of Biogeochemistry and Pollutant Dynamic, Universitätsstrasse 16, CH-8092, Zurich, Switzerland; present address: FOR, Zurich Forensic Science Institute, Zeughausstrasse 11, CH-8004, Zurich, Switzerland
| | - Hans-Peter E Kohler
- Eawag, Swiss Federal Institute of Aquatic Science and Technology, Überlandstrasse 133, CH-8600, Dübendorf, Switzerland
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28
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Shao Y, Wang J, Wang J, Du Z, Li B, Zhu L, Juhasz A, Liu X, Xu Y, Li W. Oxidative stress and genotoxic effects in earthworms induced by five imidazolium bromide ionic liquids with different alkyl chains. Chemosphere 2019; 227:570-579. [PMID: 31004823 DOI: 10.1016/j.chemosphere.2019.04.091] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Revised: 04/11/2019] [Accepted: 04/12/2019] [Indexed: 06/09/2023]
Abstract
In this study, the acute and subchronic toxicity of 1-alkyl-3-methyl imidazole bromide ionic liquids (ILs) [Cnmim]Br (n = 2, 4, 6, 10, 12) was evaluated utilizing earthworms (Eisenia fetida) as a basis for their impact on terrestrial ecosystems. The filter paper tests and artificial soil tests were conducted as acute toxicity tests to investigate the LC50 of ILs, while in subchronic toxicity tests, earthworms were exposed to ILs in artificial soil (5, 10, 20 and 40 mg kg-1) for 28 d. Reactive oxygen species (ROS), antioxidant enzymes, detoxifying enzymes and oxidative damage were measured to determine subchronic effects of ILs on E. fetida. The results showed that when the earthworms were exposed to these five ILs in acute toxicity experiments, [C2mim]Br had the lowest toxicity, as the alkyl length increased, the toxicity increased up to [C10mim]Br: a "cut-off effect" (decreased toxicity) was observed at [C12mim]Br. The results highlight the varying toxicity of ILs with different alkyl chains to E. fetida and provide valuable data for detailing the impact of ILs on ecological receptors.
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Affiliation(s)
- Yuting Shao
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Jinhua Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Jun Wang
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Zhongkun Du
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Bing Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Lusheng Zhu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Albert Juhasz
- Future Industries Institute, University of South Australia, Mawson Lakes, SA, 5095, Australia.
| | - Xiaoyan Liu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Yaqi Xu
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
| | - Wenxiu Li
- College of Resources and Environment, Shandong Agricultural University, Key Laboratory of Agricultural Environment in Universities of Shandong, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, 61 Daizong Road, Taian, 271018, China.
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Koch C, Sures B. Degradation of brominated polymeric flame retardants and effects of generated decomposition products. Chemosphere 2019; 227:329-333. [PMID: 30999173 DOI: 10.1016/j.chemosphere.2019.04.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2019] [Revised: 03/24/2019] [Accepted: 04/05/2019] [Indexed: 06/09/2023]
Abstract
Brominated flame retardants are often associated with adverse environmental effects. Nevertheless, these chemicals are required in order to comply with fire safety standards. Therefore, a better environmental profile is desirable. A "new" class of flame retardants is claimed to fulfil this request while still being feasible for established industrial processes. Different to previous brominated flame retardants, this new group is based on a polymeric structure that could indeed lead to a better environmental profile. However, not much is known about the long-term behaviour of such flame retardants. This short review summarizes what has already been published. With an annual production volume of 26,000 metric tons, "Polymeric FR" is currently the only industrially produced representative of this group. It has been shown to degrade under specific circumstances (following UV and heat exposure). Detected degradation products cause almost no acute toxicity, whereas chronic toxicity might be relevant. Nevertheless, as long as polymeric flame retardants are only used in building insulation, the actual risk seems to be rather limited.
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Affiliation(s)
- Christoph Koch
- Aquatic Ecology and Centre for Water and Environmental Research (ZWU), University Duisburg-Essen, 45141, Essen, Germany; Deutsche Rockwool GmbH & Co. KG, 45966, Gladbeck, Germany.
| | - Bernd Sures
- Aquatic Ecology and Centre for Water and Environmental Research (ZWU), University Duisburg-Essen, 45141, Essen, Germany
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Yang M, Liang LF, Yao LG, Liu HL, Guo YW. A new brominated polyacetylene from Chinese marine sponge Xestospongia testudinaria. J Asian Nat Prod Res 2019; 21:573-578. [PMID: 30612465 DOI: 10.1080/10286020.2018.1548013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 11/10/2018] [Accepted: 11/11/2018] [Indexed: 06/09/2023]
Abstract
A new brominated polyacetylene xestonariene J (1), bearing a rare 2,4-dibromo-1-ene-3-yne terminal in the molecule, along with two known related analogues (2 and 3), was obtained from Chinese marine sponge Xestospongia testudinaria. Its structure was determined on the basis of detailed spectroscopic analysis and comparison with literature data.
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Affiliation(s)
- Min Yang
- a State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203 , China
- b University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Lin-Fu Liang
- a State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203 , China
- c College of Materials Science and Engineering , Central South University of Forestry and Technology , Changsha 410004 , China
| | - Li-Gong Yao
- a State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203 , China
| | - Hai-Li Liu
- a State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203 , China
| | - Yue-Wei Guo
- a State Key Laboratory of Drug Research , Shanghai Institute of Materia Medica, Chinese Academy of Sciences , Shanghai 201203 , China
- b University of Chinese Academy of Sciences , Beijing 100049 , China
- d Open Studio for Druggability Research of Marine Natural Products , Pilot National Laboratory for Marine Science and Technology , Qingdao 266237 , China
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31
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Almásy L, Bende A. Intermolecular Interaction in Methylene Halide ( CH2F2, CH2Cl2, CH2Br2 and CH2I2) Dimers. Molecules 2019; 24:E1810. [PMID: 31083344 PMCID: PMC6539938 DOI: 10.3390/molecules24091810] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Revised: 04/27/2019] [Accepted: 05/01/2019] [Indexed: 02/06/2023] Open
Abstract
The intermolecular interaction in difluoromethane, dichloromethane, dibromomethane, and diiodomethane dimers has been investigated using high level quantum chemical methods. The potential energy curve of intermolecular interaction along the C⋯C bond distance obtained using the coupled-cluster theory with singles, doubles, and perturbative triples excitations CCSD(T) were compared with values given by the same method, but applying the local (LCCSD(T)) and the explicitly correlated (CCSD(T)-F12) approximations. The accuracy of other theoretical methods-Hartree-Fock (HF), second order Møller-Plesset perturbation (MP2), and dispersion corrected DFT theory-were also presented. In the case of MP2 level, the canonical and the local-correlation cases combined with the density-fitting technique (DF-LMP2)theories were considered, while for the dispersion-corrected DFT, the empirically-corrected BLYP-D and the M06-2Xexchange-correlation functionals were applied. In all cases, the aug-cc-pVTZ basis set was used, and the results were corrected for the basis set superposition error (BSSE) using the counterpoise method. For each molecular system, several dimer geometries were found, and their mutual orientations were compared with the nearest neighbor orientations obtained in recent neutron scattering studies. The nature of the intermolecular interaction energy was discussed.
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MESH Headings
- Dimerization
- Hydrocarbons, Brominated/analysis
- Hydrocarbons, Brominated/chemistry
- Hydrocarbons, Chlorinated/analysis
- Hydrocarbons, Chlorinated/chemistry
- Hydrocarbons, Fluorinated/analysis
- Hydrocarbons, Fluorinated/chemistry
- Hydrocarbons, Iodinated/analysis
- Hydrocarbons, Iodinated/chemistry
- Inorganic Chemicals/analysis
- Inorganic Chemicals/chemistry
- Models, Chemical
- Models, Molecular
- Quantum Theory
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Affiliation(s)
- László Almásy
- State Key Laboratory of Environment-friendly Energy Materials, Southwest University of Science and Technology, Mianyang 621010, China.
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, Konkoly Thege út 29-33, 1121 Budapest, Hungary.
| | - Attila Bende
- Molecular and Biomolecular Physics Department, National Institute for Research and Development of Isotopic and Molecular Technologies, Donat Street, No. 67-103, Ro-400293 Cluj-Napoca, Romania.
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Weggel LA, Pandya AA. Acute Administration of Desformylflustrabromine Relieves Chemically Induced Pain in CD-1 Mice. Molecules 2019; 24:molecules24050944. [PMID: 30866543 PMCID: PMC6432607 DOI: 10.3390/molecules24050944] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Revised: 02/27/2019] [Accepted: 03/04/2019] [Indexed: 01/28/2023] Open
Abstract
Neuronal nicotinic acetylcholine receptors are cell membrane-bound ion channels that are widely distributed in the central nervous system. The α4β2 subtype of neuronal nicotinic acetylcholine receptor plays an important role in modulating the signaling pathways for pain. Previous studies have shown that agonists, partial agonists, and positive allosteric modulators for the α4β2 receptors are effective in relieving pain. Desformylflustrabromine is a compound that acts as an allosteric modulator of α4β2 receptors. The aim of this study was to assess the effects of desformylflustrabromine on chemically induced pain. For this purpose, the formalin-induced pain test and the acetic acid-induced writhing response test were carried out in CD-1 mice. Both tests represent chemical assays for nociception. The results show that desformylflustrabromine is effective in producing an analgesic effect in both tests used for assessing nociception. These results suggest that desformylflustrabromine has the potential to become a clinically used drug for pain relief.
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Affiliation(s)
- Loni A Weggel
- Department of Biosciences, College of Rural and Community Development, 101D Harper Building, 810 Draanjik Drive, University of Alaska Fairbanks, Fairbanks, AK 99709-3419, USA.
| | - Anshul A Pandya
- Department of Biosciences, College of Rural and Community Development, 101D Harper Building, 810 Draanjik Drive, University of Alaska Fairbanks, Fairbanks, AK 99709-3419, USA.
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Abstract
The development of a general, nickel-catalyzed alkyl-Mizoroki-Heck reaction of unactivated alkyl bromides is described. The mild reaction proceeds efficiently using a wide range of primary and secondary alkyl bromides, and examples of intermolecular cross-couplings are provided. Reaction alkene regioselectivity is significantly enhanced over prior carbocyclizations using palladium catalysis. Mechanistic investigations are consistent with a direct carbocyclization in contrast to the auto-tandem atom-transfer cyclization and halide elimination previously observed with palladium catalysis.
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Affiliation(s)
- Megan R. Kwiatkowski
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (USA),
| | - Erik J. Alexanian
- Department of Chemistry, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599 (USA),
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Okonski K, Melymuk L, Kohoutek J, Klánová J. Hexabromocyclododecane: concentrations and isomer profiles from sources to environmental sinks. Environ Sci Pollut Res Int 2018; 25:36624-36635. [PMID: 30377961 DOI: 10.1007/s11356-018-3381-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 10/01/2018] [Indexed: 06/08/2023]
Abstract
Concentrations and isomer compositions of hexabromocyclododecane (HBCD) were measured in six matrices in the Czech Republic (HBCD technical mixture; consumer products; indoor and outdoor air at industrial, urban and background locations; soils; and sediments) to provide insight into changes in concentrations and isomer profiles between environmental sources and environmental sinks. A distinct gradient of air concentrations was observed, from 1600 ng/m3 in the industrial area to < 10 pg/m3 in urban and background air. Isomer profiles also showed a distinct gradient in air, from 95% γ-HBCD in industrial air to 40% γ-HBCD in background air, suggesting the influence of differential atmospheric transport and phototransformation of γ- to α-HBCD. Concentrations and isomer compositions in consumer products were highly variable and indicated differences between products with intentional addition of HBCD as a flame retardant versus those with HBCD as an impurity, e.g., from recycled plastic. Understanding the isomer-specific environmental distributions and processes remains important for risk assessment and toxicology, considering the continued use of HBCD and the isomer-specific differences in uptake, metabolism, and toxicity, and further, demonstrates the utility of isomer profiles to better understand environmental processes of HBCDs.
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Affiliation(s)
- Krzysztof Okonski
- Faculty of Science, RECETOX (Research Centre for Toxic Compounds in the Environment), Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Lisa Melymuk
- Faculty of Science, RECETOX (Research Centre for Toxic Compounds in the Environment), Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic.
| | - Jiří Kohoutek
- Faculty of Science, RECETOX (Research Centre for Toxic Compounds in the Environment), Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
| | - Jana Klánová
- Faculty of Science, RECETOX (Research Centre for Toxic Compounds in the Environment), Masaryk University, Kamenice 753/5, 625 00, Brno, Czech Republic
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Shen J, Smyth SA, Droste R, Delâge D. Variability of release rate of flame retardants in wastewater treatment plants. Environ Sci Pollut Res Int 2018; 25:34740-34752. [PMID: 30324373 PMCID: PMC6245005 DOI: 10.1007/s11356-018-3403-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Accepted: 10/04/2018] [Indexed: 06/08/2023]
Abstract
Information on variability is important in the assessment of the releases and potential risks of brominated flame retardants (BRFs) in the environment, but related data are limited. In this study, two release-characterizing parameters, release fraction to final effluent and influent-biosolids transfer coefficient, were used to quantify releases of five BFRs from eight secondary wastewater treatment plants (WWTPs). The five BFRs are recalcitrant, hydrophobic, and low in volatility. The two parameters for these BFRs were found to vary from day to day and season to season within individual WWTPs as well as from one WWTP to another. These temporal and spatial variations were, however, comparable to each other and both within a factor of 3 above or below the parameter averages. Averages for release fraction were in the range of 0.02-0.29 and those for influent-biosolids transfer coefficient in the range of 3-26 L/g, depending upon a given BFR at a given WWTP. These ranges and the observed factor-3 variability are not only useful for estimating releases of the five BFRs, but more importantly provide read-across data for the assessment of substances with similar physical-chemical properties.
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Affiliation(s)
- Jesse Shen
- Science and Risk Assessment Directorate, Science and Technology Branch, Environment and Climate Change Canada, 351 Saint Joseph Boulevard, Gatineau, Quebec, K1A 0H3, Canada.
| | - Shirley Anne Smyth
- Science and Risk Assessment Directorate, Science and Technology Branch, Environment and Climate Change Canada, 351 Saint Joseph Boulevard, Gatineau, Quebec, K1A 0H3, Canada
| | - Ronald Droste
- Department of Civil Engineering, University of Ottawa, Ottawa, ON, K1N 6N5, Canada
| | - Danaëlle Delâge
- Science and Risk Assessment Directorate, Science and Technology Branch, Environment and Climate Change Canada, 351 Saint Joseph Boulevard, Gatineau, Quebec, K1A 0H3, Canada
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36
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Liu B, Yang Y, Sun H, Sun Z. Dissociative Ionization and Coulomb Explosion of Molecular Bromocyclopropane in an Intense Femtosecond Laser Field. Molecules 2018; 23:molecules23123096. [PMID: 30486415 PMCID: PMC6321640 DOI: 10.3390/molecules23123096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Revised: 11/20/2018] [Accepted: 11/24/2018] [Indexed: 11/16/2022] Open
Abstract
The dissociative ionization and Coulomb explosion of molecular bromocyclopropane (BCP) has been experimentally investigated by time-of-flight mass spectrum and dc-slice imaging technology. The sliced 2D images, kinetic energy releases and angular distributions of the fragment ions are obtained under the intense femtosecond laser fields (8.0 × 1013–2.0 × 1014 W/cm2). The results indicated that the low kinetic energy release (KER) components come from dissociative ionization of BCP+, while the high KER components come from Coulomb explosion of BCP2+. The chemical reaction path of BCP+ has been calculated by ab initio calculation, furthermore, the C-Br bond cleavage involved Coulomb explosion channels have been revealed, and the corresponding dehydrogenation mechanism has been confirmed.
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Affiliation(s)
- Botong Liu
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
| | - Yan Yang
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
| | - Haitao Sun
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
| | - Zhenrong Sun
- State Key Laboratory of Precision Spectroscopy, School of Physics and Materials Science, East China Normal University, Shanghai 200062, China.
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
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Lin W, Li X, Yang M, Lee K, Chen B, Zhang BH. Brominated Flame Retardants, Microplastics, and Biocides in the Marine Environment: Recent Updates of Occurrence, Analysis, and Impacts. Adv Mar Biol 2018; 81:167-211. [PMID: 30471656 DOI: 10.1016/bs.amb.2018.09.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Emerging contaminants (ECs) may pose adverse effects on the marine ecosystem and human health. Based on the analysis of publications filed in recent years, this paper provides a comprehensive overview on three prominent groups of ECs, i.e., brominated flame retardants, microplastics, and biocides. It includes detailed discussions on: (1) the occurrence of ECs in seawater, sediment, and biota; (2) analytical detection and monitoring approaches for these target ECs; and (3) the biological impacts of the ECs on humans and other trophic levels. This review provides a summary of recent advances in the field and remaining knowledge gaps to address, to enable the assessment of risk and support the development of regulations and mitigation technologies for the control of ECs in the marine environment.
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Affiliation(s)
- Weiyun Lin
- Faculty of Engineering and Applied Science, Memorial University, St. John's, NL, Canada
| | - Xixi Li
- The Northern Region Persistent Organic Pollution Control (NRPOP) Laboratory, Faculty of Engineering and Applied Science, Memorial University of Newfoundland, St. John's, NL, Canada
| | - Min Yang
- Faculty of Engineering and Applied Science, Memorial University, St. John's, NL, Canada
| | - Kenneth Lee
- Ecosystem Science, Fisheries and Oceans Canada, Ottawa, ON, Canada
| | - Bing Chen
- Faculty of Engineering and Applied Science, Memorial University, St. John's, NL, Canada
| | - Baiyu Helen Zhang
- Faculty of Engineering and Applied Science, Memorial University, St. John's, NL, Canada.
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38
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Pirard C, Charlier C. Simple and fast method for the measurement of legacy and novel brominated flame retardants in human serum. Chemosphere 2018; 211:918-925. [PMID: 30119023 DOI: 10.1016/j.chemosphere.2018.08.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 08/02/2018] [Accepted: 08/03/2018] [Indexed: 06/08/2023]
Abstract
Recent and reliable human biomonitoring data on brominated flame retardants (BFRs), either legacy or new BFRs, are still needed to assess human exposure. The aim of this work was therefore to develop and validate an accurate, fast and user-friendly analytical strategy for the determination of 15 legacy and novel BFRs in human serum namely 8 polybrominated diphenylethers (BDE-28, -47, -99, -100, -153, -154, -183, and -209), 1 hexabromobiphenyl (PBB-153), and 6 novel BFRs (pentabromotoluene, hexabromobenzene, pentabromoethylbenzene, 2-ethylhexy-2,3,4,5-tetrabromobenzoate, 1,2-bis(2,4,6-tribromophenoxy)ethane, and decabromodiphenylethane). This analytical procedure consisted in a simple liquid-liquid extraction followed by elution on a PHREE cartridge avoiding further laborious purification steps. The final determination was performed by gas chromatography coupled to mass spectrometry in electron capture negative ionization mode (GC-ECNI-MS). The 15 m long RTX-1614 allowed the simultaneous measurement of the 15 BFRs including low and high brominated species within a single injection on a single column. Except for 2-ethylhexy-2,3,4,5-tetrabromobenzoate (EHTBB) which showed very high response variations resulting in poor linearity, trueness and precision, and decabromodiphenylethane for which very low sensitivity was achieved, the 13 other BFRs passed the validation process with recoveries varying between 56 and 82%, and limits of quantification (LOQs) ranging from 2.5 to 6.0 pg/ml (34.5 pg/ml for BDE-209). Within the validated range of concentrations, the relative bias from the introduced levels were below 20% while the intra and inter precisions were maintained below 15%. The reliability of the technique was confirmed by successfully analyzing interlaboratory test materials (AMAP ring test for POPs in human serum).
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Affiliation(s)
- Catherine Pirard
- Laboratory of Clinical, Forensic and Environmental Toxicology, CHU of Liege, B35, 4000 Liege, Belgium; Center for Interdisciplinary Research on Medicines (CIRM), University of Liege (ULg), CHU (B35), 4000 Liege, Belgium.
| | - Corinne Charlier
- Laboratory of Clinical, Forensic and Environmental Toxicology, CHU of Liege, B35, 4000 Liege, Belgium; Center for Interdisciplinary Research on Medicines (CIRM), University of Liege (ULg), CHU (B35), 4000 Liege, Belgium.
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39
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Khaled A, Richard C, Rivaton A, Jaber F, Sleiman M. Photodegradation of brominated flame retardants in polystyrene: Quantum yields, products and influencing factors. Chemosphere 2018; 211:943-951. [PMID: 30223340 DOI: 10.1016/j.chemosphere.2018.07.147] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 07/21/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
Brominated flame retardants (BFRs) are widely used as additives in plastics, textiles and electronics materials. Here, we investigated the photodegradation of four BFRs including decabromobiphenylether (BDE-209), tetrabromobipsphenol A (TBBPA), tetrabromobisphenol A-bis(2,3-dibromopropylether) (TBBPA-DBPE) and tetrabromobisphenol A bis (allyl) ether (TBBPA-BAE). Experiments were carried out in polystyrene (PS) films using monochromatic and polychromatic irradiations. For comparison, irradiations were also carried in a solvent (tetrahydrofuran: THF). Monitoring of BFR degradation was performed using bulk and surface infrared (IR) measurements, as well as by extraction and HPLC-UV. Photoproducts were characterized using HPLC-high resolution electrospray ionization mass spectrometry (HPLC-ESI-Orbitrap-MS). All four BFRs underwent photochemical transformation in THF at 290 nm with a quantum yield (Φ) ranging from 0.05 for TBBPA to 0.27 for BDE-209, indicating an increase of photoreactivity with the number of Br atoms in BFRs. On the other hand, no major difference in the Φ values was observed when BFRs were embedded in PS films (Φ: 0.82-0.89). The higher photoreactivity in PS appears to be associated with a fast oxidation of PS as revealed by infrared (IR) analysis and yellowing of the films. Interestingly, the faster the yellowing occurred, the faster the BFR degradation was inhibited due to light screening effect. Several major photoproducts were identified for TBBPA and TBBPA-DBPE. Additional photoproducts possibly arising from PS oxidation and bromination by Br● were observed for the first time. This work provides a better understanding of the reactivity and fate of BFRs in polymers allowing for a better assessment of their environmental impacts.
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Affiliation(s)
- Amina Khaled
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Claire Richard
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Agnès Rivaton
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France
| | - Farouk Jaber
- Laboratory of Analysis of Organic Compounds (509), Faculty of Sciences I, Lebanese University, Hadath, Beirut, Lebanon
| | - Mohamad Sleiman
- Université Clermont Auvergne, CNRS, SIGMA Clermont, Institut de Chimie de Clermont-Ferrand, F-63000 Clermont-Ferrand, France.
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Liu X, Zheng M, Wang L, Ke R, Lou Y, Zhang X, Dong X, Zhang Y. Sorption behaviors of tris-(2,3-dibromopropyl) isocyanurate and hexabromocyclododecanes on polypropylene microplastics. Mar Pollut Bull 2018; 135:581-586. [PMID: 30301076 DOI: 10.1016/j.marpolbul.2018.07.061] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Revised: 07/17/2018] [Accepted: 07/21/2018] [Indexed: 06/08/2023]
Abstract
In recent years, microplastics in oceans have become a serious environmental problem and the focus of attention. In the present study, the sorption of TBC and HBCDs by microplastics in simulated seawater is examined. The effects of particle size, temperature, salinity, and concentration on the adsorption of TBC and HBCDs by microplastics are studied. Results indicate that the first-order adsorption kinetic model is more suitable than the pseudo-second-order kinetic model to describe adsorption. The equilibrium adsorption times are 15 h and 10 h for TBC and HBCDs, respectively. The adsorption capacity increases with the decrease in particle size. The adsorption capacity gradually increases at first and then decreases with the increase in salinity and temperature. The maximum adsorption capacity is at 15 °C and 14% salinity. Compared with the linear and Freundlich models, the Langmuir model is more suitable; this indicates that the main adsorption mechanism might be chemical adsorption.
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Affiliation(s)
- Xiaowen Liu
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Minggang Zheng
- Research Center for Marine Ecology, The First Institute of Oceanic Administration of China, Qingdao 266061, China
| | - Ling Wang
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China.
| | - Runhui Ke
- National Food Quality Supervision and Inspection Center, Beijing 100015, China
| | - Yinghua Lou
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Xiaojun Zhang
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Xiaofeng Dong
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
| | - Yu Zhang
- Environmental Science and Engineering, Qingdao University, Qingdao 266071, China
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41
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Barghi M, Shin ES, Choi SD, Dahmardeh Behrooz R, Chang YS. HBCD and TBBPA in human scalp hair: Evidence of internal exposure. Chemosphere 2018; 207:70-77. [PMID: 29772426 DOI: 10.1016/j.chemosphere.2018.05.032] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/03/2018] [Accepted: 05/04/2018] [Indexed: 06/08/2023]
Abstract
Human biomonitoring is a reliable method for evaluating human exposure to specific contaminants. Although blood is an ideal matrix for monitoring purposes, it is regarded as an invasive matrix. Therefore, current developments in the field of human biomonitoring are based on introducing new methods that use non-invasive matrices, such as hair. In this study, we examined the efficiencies of several extraction methods for the analysis of hexabromocyclododecane (HBCD) and tetrabromobisphenol-A (TBBPA) in human hair. The selected pretreatment method was validated through a general QA/QC process that included spiking experiments, and then, the method was used for the determination of HBCD and TBBPA concentrations in scalp hair samples collected from individuals in Korea (n = 24) and Iran (n = 15). The HBCD and TBBPA concentrations in the collected hair samples ranged from ND to 3.24 ng g-1 and ND to 16.04 ng g-1, respectively. Significantly higher concentrations of TBBPA were found in hair samples from Korea than those in hair samples from Iran (p < 0.05), which is expected to be the result of the large market and higher exposure of TBBPA in Korea. HBCD was not detected in hair samples from Iran. According to our knowledge this is the first study demonstrating the presence of TBBPA in human hair with nonspecific exposure. Lastly, we investigated the important factors that influence the interpretation of the contributions of endogenous and exogenous contaminations in hair. Based on the information, the HBCD and TBBPA in the collected hair samples were most likely from endogenous exposure. Therefore, our study showed that hair is potentially a suitable indicator for the monitoring of internal exposure to HBCD and TBBPA in different populations.
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Affiliation(s)
- Mandana Barghi
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Republic of Korea
| | - Eun-Su Shin
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Republic of Korea
| | - Sung-Deuk Choi
- School of Urban and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulsan, 44919, Republic of Korea
| | - Reza Dahmardeh Behrooz
- Department of Environmental Sciences, Faculty of Natural Resources, University of Zabol, Zabol, Iran
| | - Yoon-Seok Chang
- Division of Environmental Science and Engineering, Pohang University of Science and Technology (POSTECH), 77 Cheongam-ro, Pohang, 37673, Republic of Korea.
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42
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Heeb NV, Mazenauer M, Wyss S, Geueke B, Kohler HPE, Lienemann P. Kinetics and stereochemistry of LinB-catalyzed δ-HBCD transformation: Comparison of in vitro and in silico results. Chemosphere 2018; 207:118-129. [PMID: 29793023 DOI: 10.1016/j.chemosphere.2018.05.057] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/04/2018] [Accepted: 05/09/2018] [Indexed: 06/08/2023]
Abstract
LinB is a haloalkane dehalogenase found in Sphingobium indicum B90A, an aerobic bacterium isolated from contaminated soils of hexachlorocyclohexane (HCH) dumpsites. We showed that this enzyme also converts hexabromocyclododecanes (HBCDs). Here we give new insights in the kinetics and stereochemistry of the enzymatic transformation of δ-HBCD, which resulted in the formation of two pentabromocyclododecanols (PBCDols) as first- (P1δ, P2δ) and two tetrabromocyclododecadiols (TBCDdiols) as second-generation products (T1δ, T2δ). Enzymatic transformations of δ-HBCD, α1-PBCDol, one of the transformation products, and α2-PBCDol, its enantiomer, were studied and modeled with Michaelis-Menten (MM) kinetics. Respective MM-parameters KM, vmax, kcat/KM indicated that δ-HBCD is the best LinB substrate followed by α2- and α1-PBCDol. The stereochemistry of these transformations was modeled in silico, investigating respective enzyme-substrate (ES) and enzyme-product (EP) complexes. One of the four predicted ES-complexes led to the PBCDol product P1δ, identical to α2-PBCDol with the 1R,2R,5S,6R,9R,10S-configuration. An SN2-like substitution of bromine at C6 of δ-HBCD by Asp-108 of LinB and subsequent hydrolysis of the alkyl-enzyme led to α2-PBCDol. Modeling results further indicate that backside attacks at C1, C9 and C10 are reasonable too, selectively binding leaving bromide ions in a halide pocket found in LinB. Docking with α2-PBCDol, also allowed productive enzyme binding. A TBCD-1,5-diol with the 1S,2S,5R,6R,9S,10R-configuration is the predicted second-generation product T1δ. In conclusion, in vitro- and in silico findings now allow a detailed description of step-wise enzymatic dehalohydroxylation reactions of δ-HBCD to specific PBCDols and TBCDdiols at Å-resolution and predictions of their stereochemistry.
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Affiliation(s)
- Norbert V Heeb
- Swiss Federal Institute for Materials Science and Technology (Empa), Laboratory of Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland.
| | - Manuel Mazenauer
- Swiss Federal Institute for Materials Science and Technology (Empa), Laboratory of Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland; Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Reidbach, 8820 Wädenswil, Switzerland
| | - Simon Wyss
- Swiss Federal Institute for Materials Science and Technology (Empa), Laboratory of Advanced Analytical Technologies, Überlandstrasse 129, CH-8600, Dübendorf, Switzerland; Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Reidbach, 8820 Wädenswil, Switzerland
| | - Birgit Geueke
- Swiss Federal Institute of Aquatic Research and Technology (Eawag), Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Hans-Peter E Kohler
- Swiss Federal Institute of Aquatic Research and Technology (Eawag), Überlandstrasse 129, 8600 Dübendorf, Switzerland
| | - Peter Lienemann
- Zurich University of Applied Sciences, Institute of Chemistry and Biological Chemistry, Reidbach, 8820 Wädenswil, Switzerland
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Tang J, Li X, Yu X, Li G, Khan S, Cai C. Application of triolein-embedded cellulose acetate membrane (TECAM) passive sampler to study phase distribution of hexabromocyclododecanes (HBCDs) in sediment. Environ Sci Pollut Res Int 2018; 25:20823-20832. [PMID: 29761355 DOI: 10.1007/s11356-018-2254-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/02/2018] [Accepted: 05/07/2018] [Indexed: 06/08/2023]
Abstract
Hexabromocyclododecanes (HBCDs) are a class of widely used brominated flame retardants (BFRs) that exhibit strong hydrophobicity. The ubiquity and persistence of HBCDs in sediment have attracted significant attention because of public health concerns. The environmental fate and ecological risks of HBCDs closely depend on their phase distribution in sediments. However, little information is available regarding the freely dissolved concentrations (Cfree) of HBCDs in sediment porewater. In this study, we developed a method to measure Cfree of HBCDs in sediment porewater using triolein-embedded cellulose acetate membranes (TECAM). The TECAM-to-water partitioning coefficient (log KTECAM) was 4.69, 4.77, and 4.63 for α-HBCD, β-HBCD, and γ-HBCD, respectively. In sediments, HBCDs sorbed to the sediment solid phase accounted for more than 99% of the total chemical mass. The dissolved organic carbon (DOC)-water partition coefficient (KDOC) values were derived from TECAM measurements, and the log KDOC values ranged from 5.77 to 6.23 for the three HBCD diastereomers, suggesting a strong tendency for HBCDs to sorb to DOC. The high sorption of HBDCs for DOC implies a potential for DOC-facilitated transport which may enhance the environmental mobility of HBCDs.
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Affiliation(s)
- Jianfeng Tang
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China.
- Ningbo Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo, 315800, China.
- Zhejiang Provincial Key Laboratory of Health Risk Factors for Seafood, Zhoushan Municipal Center for Disease Control and Prevention, Zhoushan, 316021, China.
| | - Xinhu Li
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Xinwei Yu
- Zhejiang Provincial Key Laboratory of Health Risk Factors for Seafood, Zhoushan Municipal Center for Disease Control and Prevention, Zhoushan, 316021, China
| | - Gang Li
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
- Ningbo Key Laboratory of Urban Environmental Processes and Pollution Control, Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo, 315800, China
| | - Sardar Khan
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
| | - Chao Cai
- Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, 361021, China
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Abstract
Nickel-catalyzed cross-electrophile couplings have recently emerged as highly effective and practical methods for the formation of C-C bonds. By merging this process with well-established π-π coupling chemistry, a new method for the synthesis of tetrasubstituted alkenes has been developed. The procedure relies on the use of chlorosilanes as a means of generating reactive vinylnickel intermediates, which are capable of undergoing a reductive cross-electrophile coupling with alkyl halides. The method not only generates highly substituted allylic alcohol derivatives but also obviates the need for stoichiometric organometallic nucleophiles and provides greatly improved scope and functional group tolerance compared with previously developed methods.
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Affiliation(s)
- Kirk W. Shimkin
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan, 48109-1055, United States
| | - John Montgomery
- Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan, 48109-1055, United States
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45
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Xia W, Wang J, Yang H, Zhang H, Yang B, Zeng Y, Xu J, Li Z, Qian M. Bioaccumulation and Distribution of Hexabromocyclododecane Isomers in Duck Tissues. Bull Environ Contam Toxicol 2018; 100:754-759. [PMID: 29713751 DOI: 10.1007/s00128-018-2342-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
Eighty ducks (Sheldrake, Anas platyrhynchos) from Zhejiang Province, China were fed capsules containing commercialized hexabromocyclododecanes (HBCDs) at low (0.8 mg/kg/day) or high (1.6 mg/kg/day) exposure level, or only maize starch for 21 days. Then the next 21 days was set as depuration period. Ducks were euthanizated at 0, 7, 14 and 21 days after last dose and ten duck tissues including skin, tongue, intestines, heart, gizzard, muscle, liver, lung, brain and blood were sampled, separately. Three HBCDs including α-HBCD, β-HBCD and γ-HBCD in duck tissue samples were analyzed. At the end of depuration period, the total HBCDs concentration in skin was significantly higher than those in the other tissues (p < 0.05). The elimination rates of the three isomers in skin, tongue, intestines, heart, gizzard and brain were in the order β- > γ- > α-HBCD. The enantioselectivity of three HBCDs enantiomers was also studied in ten duck tissues. It was shown that the EF (enrichment factor) for two γ-HBCD enantiomers was significant lower than 0.5 (p < 0.05) in gizzard, heart, muscle, tongue, intestinal and liver at the end of depuration day, showing a selective accumulation of (+)-γ-HBCD in these tissues. This study provided a reference for evaluation on the accumulation of the persistent contamination of HBCDs in edible poultry.
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Affiliation(s)
- Wei Xia
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Jianmei Wang
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Hua Yang
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Hu Zhang
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Bo Yang
- Hubei Engineering Research Center of Viral Vector, Wuhan Institute of Bioengineering, Wuhan, 430415, People's Republic of China
| | - Yinhuan Zeng
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Jie Xu
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China
| | - Zuguang Li
- College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, People's Republic of China.
| | - Mingrong Qian
- State Key Lab Breeding Base Zhejiang Sustainable, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, Zhejiang, People's Republic of China.
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Peng YH, Chen YJ, Chang M, Shih YH. The effect of zerovalent iron on the microbial degradation of hexabromocyclododecane. Chemosphere 2018; 200:419-426. [PMID: 29501032 DOI: 10.1016/j.chemosphere.2018.02.123] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/17/2018] [Accepted: 02/20/2018] [Indexed: 06/08/2023]
Abstract
Hexabromocyclododecane (HBCD), a commonly used brominated flame retardant (BFR), has been listed as a persistent organic pollutant (POP). In order to remediate HBCD in the environment, the influence of microscale zerovalent iron (MZVI) on the HBCD degrading microcosm was evaluated. In the acclimated microcosm collected from river sediment, 49% of HBCD was initially removed through adsorption and then 30% of HBCD was biodegraded through non-debromination processes. In contrast to MZVI only, over 60% of HBCD was gradually degraded by MZVI through a debromination reaction. In the microcosm-MZVI combined system, the biodegradation ability of the microcosm was inhibited. The aqueous chemistry was changed by the addition of MZVI, which led to the alteration of microbial composition and biodegradation ability. These better understandings can facilitate an evaluation of the impact of MZVI on HBCD biodegradation when ZVI was used to remediate this BFR.
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Affiliation(s)
- Yu-Huei Peng
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei City, 10617, Taiwan
| | - Ya-Jou Chen
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei City, 10617, Taiwan
| | - Ming Chang
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei City, 10617, Taiwan
| | - Yang-Hsin Shih
- Department of Agricultural Chemistry, National Taiwan University, No. 1, Sec. 4, Roosevelt Road, Taipei City, 10617, Taiwan.
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47
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Olukunle OI, Venier M, Hites RA, Salamova A. Atmospheric concentrations of hexabromocyclododecane (HBCDD) diastereomers in the Great Lakes region. Chemosphere 2018; 200:464-470. [PMID: 29501037 DOI: 10.1016/j.chemosphere.2018.02.109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/15/2018] [Accepted: 02/17/2018] [Indexed: 06/08/2023]
Abstract
The concentrations of α-, β-, and γ-hexabromocyclododecane (HBCDD) diastereomers in atmospheric particle phase samples were determined at four United States Integrated Atmospheric Deposition Network (IADN) sites located in the North American Great Lakes basin collected between 1 January and 31 December 2014. The concentrations ranged from 0.37 to 8.9 pg/m3, 0.12-4.0 pg/m3, and 0.26-22 pg/m3 for α-, β-, and γ-HBCDD, respectively among the four sampling sites. The median ΣHBCDD concentrations for the four sites were 2.0 pg/m3, 2.1 pg/m3, 1.7 pg/m3 and 5.2 pg/m3 for Chicago, Cleveland, Sturgeon Point and Sleeping Bear Dunes, respectively. Higher levels of ∑HBCDD were observed at the remote site of Sleeping Bear Dunes with comparable levels at the remaining three sites. α-HBCDD and γ-HBCDD were the dominant isomers with an average contribution of about 40% and 50% to ΣHBCDD concentrations, respectively. These HBCDD concentrations were compared with the levels of other brominated flame retardants measured in these samples, including polybrominated diphenyl ethers (PBDEs), 2,3,4,5-tetrabromoethylhexyl benzoate (EHTBB), bis(2-ethylhexyl) tetrabromophthalate (BEHTBP), and decabromodiphenylethane (DBDPE). ∑HBCDD concentrations were significantly lower than or indistinguishable from those of PBDEs, EHTBB, BEHTBP, and DBDPE at all sites except Sleeping Bear Dunes. No significant correlations were found between ΣHBCDD and ΣPBDE, EHTBB, BEHTBP, and DBDPE concentrations, suggesting a different source of HBCDD contamination. This is the first study reporting concentrations of HBCDD isomers in the Great Lakes ambient air, and our results indicate that HBCDD is ubiquitous in the Great Lakes basin, including at remote sites.
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Affiliation(s)
- Olubiyi I Olukunle
- School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, USA
| | - Marta Venier
- School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, USA
| | - Ronald A Hites
- School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, USA
| | - Amina Salamova
- School of Public and Environmental Affairs, Indiana University, Bloomington, IN 47405, USA.
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Wu X, Iwata T, Scharf A, Qin T, Reichl KD, Porco JA. Asymmetric Synthesis of Gonytolide A: Strategic Use of an Aryl Halide Blocking Group for Oxidative Coupling. J Am Chem Soc 2018; 140:5969-5975. [PMID: 29658717 PMCID: PMC5943148 DOI: 10.1021/jacs.8b02535] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The first synthesis of the chromanone lactone dimer gonytolide A has been achieved employing vanadium(V)-mediated oxidative coupling of the monomer gonytolide C. An o-bromine blocking group strategy was employed to favor para- para coupling and to enable kinetic resolution of (±)-gonytolide C. Asymmetric conjugate reduction enabled practical kinetic resolution of a chiral, racemic precursor and the asymmetric synthesis of (+)-gonytolide A and its atropisomer.
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Affiliation(s)
| | | | - Adam Scharf
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - Tian Qin
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - Kyle D. Reichl
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
| | - John A. Porco
- Department of Chemistry and Center for Molecular Discovery (BU-CMD),
Boston University, Boston, Massachusetts 02215, United States
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49
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Emery KJ, Young A, Arokianathar JN, Tuttle T, Murphy JA. KO tBu as a Single Electron Donor? Revisiting the Halogenation of Alkanes with CBr₄ and CCl₄. Molecules 2018; 23:molecules23051055. [PMID: 29724009 PMCID: PMC6102552 DOI: 10.3390/molecules23051055] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 04/24/2018] [Accepted: 04/26/2018] [Indexed: 11/29/2022] Open
Abstract
The search for reactions where KOtBu and other tert-alkoxides might behave as single electron donors led us to explore their reactions with tetrahalomethanes, CX4, in the presence of adamantane. We recently reported the halogenation of adamantane under these conditions. These reactions appeared to mirror the analogous known reaction of NaOH with CBr4 under phase-transfer conditions, where initiation features single electron transfer from a hydroxide ion to CBr4. We now report evidence from experimental and computational studies that KOtBu and other alkoxide reagents do not go through an analogous electron transfer. Rather, the alkoxides form hypohalites upon reacting with CBr4 or CCl4, and homolytic decomposition of appropriate hypohalites initiates the halogenation of adamantane.
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Affiliation(s)
- Katie J Emery
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - Allan Young
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - J Norman Arokianathar
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - Tell Tuttle
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, UK.
| | - John A Murphy
- Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, UK.
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50
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Abdallah MAE, Sharkey M, Berresheim H, Harrad S. Hexabromocyclododecane in polystyrene packaging: A downside of recycling? Chemosphere 2018; 199:612-616. [PMID: 29459351 DOI: 10.1016/j.chemosphere.2018.02.084] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 02/12/2018] [Accepted: 02/13/2018] [Indexed: 06/08/2023]
Abstract
While there are no regulatory fire safety obligations for polystyrene (PS) when used as packaging material, concerns exist that such packaging material may contain the flame retardant hexabromocyclododecane (HBCDD) as a result of uncontrolled recycling activities. To evaluate these concerns, we collected 50 samples of PS packaging materials from the UK and 20 from Ireland. HBCDD was detected in 63 (90%) of samples, with concentrations in 4 samples from Ireland exceeding the EU's low POP concentration limit (LPCL) of 0.1% above which articles may not be recycled. Moreover, 2 further samples contained HBCDD >0.01%. While our samples were obtained in the 12 month period prior to the March 2016 introduction of the EU's 0.01% concentration limit above which articles may not be placed on the market, our data suggest that continued monitoring is required to assess compliance with this limit value. Ratios of α vs. γ-HBCDD in our EPS packaging samples (average = 0.63) exceeded significantly (p = 0.025) those in EPS building insulation material samples (average = 0.24) reported previously for Ireland. This shift towards α-HBCDD in packaging EPS is consistent with the additional thermal processing experienced by recycled PS and suggests the source of HBCDD in PS packaging is recycled PS insulation foam. This is of concern owing to the higher bioavailability and lower metabolic clearance of α-HBCDD compared to the β- and γ-isomers.
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Affiliation(s)
- Mohamed Abou-Elwafa Abdallah
- School of Geography, Earth & Environmental Sciences, University of Birmingham, UK; Department of Analytical Chemistry, Faculty of Pharmacy, Assiut University, 71526 Assiut, Egypt
| | - Martin Sharkey
- School of Physics, National University of Ireland Galway, Ireland
| | | | - Stuart Harrad
- School of Geography, Earth & Environmental Sciences, University of Birmingham, UK.
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