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Rubio-Camacho M, Martínez-Tomé MJ, Mira A, Mallavia R, Mateo CR. Formation of Multicolor Nanogels Based on Cationic Polyfluorenes and Poly(methyl vinyl ether-alt-maleic monoethyl ester): Potential Use as pH-Responsive Fluorescent Drug Carriers. Int J Mol Sci 2021; 22:9607. [PMID: 34502514 PMCID: PMC8431760 DOI: 10.3390/ijms22179607] [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: 08/09/2021] [Revised: 08/26/2021] [Accepted: 09/01/2021] [Indexed: 12/19/2022] Open
Abstract
In this study, we employed the copolymer poly(methyl vinyl ether-alt-maleic monoethyl ester) (PMVEMA-Es) and three fluorene-based cationic conjugated polyelectrolytes to develop fluorescent nanoparticles with emission in the blue, green and red spectral regions. The size, Zeta Potential, polydispersity, morphology, time-stability and fluorescent properties of these nanoparticles were characterized, as well as the nature of the interaction between both PMVEMA-Es and fluorescent polyelectrolytes. Because PMVEMA-Es contains a carboxylic acid group in its structure, the effects of pH and ionic strength on the nanoparticles were also evaluated, finding that the size is responsive to pH and ionic strength, largely swelling at physiological pH and returning to their initial size at acidic pHs. Thus, the developed fluorescent nanoparticles can be categorized as pH-sensitive fluorescent nanogels, since they possess the properties of both pH-responsive hydrogels and nanoparticulate systems. Doxorubicin (DOX) was used as a model drug to show the capacity of the blue-emitting nanogels to hold drugs in acidic media and release them at physiological pH, from changes in the fluorescence properties of both nanoparticles and DOX. In addition, preliminary studies by super-resolution confocal microscopy were performed, regarding their potential use as image probes.
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Affiliation(s)
| | - María José Martínez-Tomé
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández, 03202 Elche, Spain; (M.R.-C.); (A.M.); (R.M.)
| | | | | | - Carmen Reyes Mateo
- Instituto de Investigación, Desarrollo e Innovación en Biotecnología Sanitaria de Elche (IDiBE), Universidad Miguel Hernández, 03202 Elche, Spain; (M.R.-C.); (A.M.); (R.M.)
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2
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Adams SA, Gerbaulet M, Schulz S, Gillespie RG, Uhl G. Chemical Species Recognition in a Tetragnatha Spider (Araneae: Tetragnathidae). J Chem Ecol 2021; 47:63-72. [PMID: 33392896 DOI: 10.1007/s10886-020-01237-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 11/12/2020] [Accepted: 11/26/2020] [Indexed: 11/27/2022]
Abstract
Much of our knowledge regarding the role of chemicals in species recognition in arthropods is based on a few taxonomic groups, predominantly insect pest species. To investigate the chemical underpinnings of species recognition cues in other arthropods, we conducted mate choice experiments and analyzed the chemical profiles of two species in the long-jawed spider genus Tetragnatha from allopatric populations across two different continents. In two separate bioassays, in which male T. extensa spiders were presented with either web silk or extracts from the silk of conspecific and heterospecific females, males consistently chose the silk or silk extract of conspecific females over those of heterospecifics. We examined the chemistry affecting this response using gas chromatography/mass spectrometry to analyze silk and whole-body extracts of the spiders. The major compounds in the extracts were identified as long chain aliphatic methyl ethers. The chemical profiles of the two species differed: the T. extensa profile consisted of 12,20-dimethylnonacosyl methyl ether (A), 8,14,20-trimethylnonacosyl methyl ether (B), and 6,14,20-trimethylnonacosyl methyl ether (C), while the profile of T. versicolor consisted of B and 14,20-dimethylnonacosyl methyl ether (D). Within each species, chemical profiles of females and males did not differ. Our results suggest that these methyl ethers are involved in species recognition of Tetragnatha spiders. This is the first study to propose compounds involved in species recognition in spiders.
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Affiliation(s)
- Seira A Adams
- Department of Environmental Science, Policy, and Management, University of California-Berkeley, 130 Mulford Hall, #3114, Berkeley, CA, 94720-3114, USA.
| | - Moritz Gerbaulet
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Stefan Schulz
- Institute of Organic Chemistry, Technische Universität Braunschweig, Hagenring 30, 38106, Braunschweig, Germany
| | - Rosemary G Gillespie
- Department of Environmental Science, Policy, and Management, University of California-Berkeley, 130 Mulford Hall, #3114, Berkeley, CA, 94720-3114, USA
| | - Gabriele Uhl
- Department of General and Systematic Zoology, Zoological Institute and Museum, University of Greifswald, Loitzer Straße 26, 17489, Greifswald, Germany
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3
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Julien M, Gori D, Höhener P, Robins RJ, Remaud GS. Intramolecular isotope effects during permanganate oxidation and acid hydrolysis of methyl tert-butyl ether. Chemosphere 2020; 248:125975. [PMID: 32007772 DOI: 10.1016/j.chemosphere.2020.125975] [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] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 10/01/2019] [Accepted: 01/19/2020] [Indexed: 06/10/2023]
Abstract
Stable isotopes have been widely used to monitor remediation of environmental contaminants over the last decades. This approach gives a good mechanistic description of natural or assisted degradation of organic pollutants, such as methyl tert-butyl ether (MTBE). Since abiotic degradation seems to be the most promising assisted attenuation method, the isotopic fractionation associated with oxidation and hydrolysis processes need to be further investigated in order to understand better these processes and make their monitoring more efficient. In this study, position-specific isotope effects (PSIEs) associated with permanganate oxidation and acid hydrolysis of MTBE were determined using isotope ratio monitoring by 13C Nuclear Magnetic Resonance Spectrometry (irm-13C NMR) combined with isotope ratio monitoring by Mass Spectrometry (irm-MS). The use of this Position-Specific Isotopic Analysis (PSIA) method makes it possible to observe a specific normal isotope effect (IE) associated with each of these two abiotic degradation mechanisms. The present work demonstrates that the 13C isotope pattern of the main degradation product, tert-butyl alcohol (TBA), depends on the chemical reaction by which it is produced. Furthermore, this study also demonstrates that PSIA at natural abundance can give new insights into reaction mechanisms and that this methodology is very promising for the future of modeling the remediation of organic contaminants.
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Affiliation(s)
- Maxime Julien
- Department of Environmental Chemistry and Engineering, Tokyo Institute of Technology, 4259 Nagatsuta-cho, Midori-ku, Yokohama, Kanagawa, 226-8503, Japan; EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière BP 92208, F-44322, Nantes, France.
| | - Didier Gori
- University of Aix-Marseille-CNRS, Laboratoire Chimie Environnement, UMR 7376, Place Victor Hugo 3, 13331 Marseille, France
| | - Patrick Höhener
- University of Aix-Marseille-CNRS, Laboratoire Chimie Environnement, UMR 7376, Place Victor Hugo 3, 13331 Marseille, France
| | - Richard J Robins
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière BP 92208, F-44322, Nantes, France
| | - Gérald S Remaud
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230, 2 Rue de la Houssinière BP 92208, F-44322, Nantes, France
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4
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Chen L, Zhu W, Lin NX, Mu B, Fan XH, Wang CY, Chen HM, Zhong J. Mechanism of separation and removal of water from dewatered sludge using L-DME to dissolve hydrophilic organic matter. Chemosphere 2020; 246:125648. [PMID: 31891851 DOI: 10.1016/j.chemosphere.2019.125648] [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] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 12/07/2019] [Accepted: 12/12/2019] [Indexed: 06/10/2023]
Abstract
Difficulties in advanced dewatering of dewatered sludge hinder sludge reduction and resource utilization. L-DME (liquified dimethyl ether) has been recently used for dewatering, but the effect of organic matter dissolution using L-DME during desorption and dehydration on water removal is not clear. In this study, dewatered sludge from urban sewage treatment plants was used to conduct experiments in sequencing dissolution-separation reactors. The changes in the dehydration rate, bound water and various organic matter levels at different times, L-DME additions, and the temperature were measured. The results show that L-DME can remove 90% of water, 100% of lipids, and 8-12% of organic matter in dewatered sludge. L-DME was mixed with the semi-like colloidal sludge, and high separation of water was achieved by mixing the L-DME with water and dissolving the hydrophilic organic matter to convert the solid-like into a two-phase (solid and liquid) substance, which can be easily separated. The dissolution of hydrophilic organic matter such as polysaccharides and proteins by L-DME promotes the conversion of bound water into free water, which is key to total water removal.
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Affiliation(s)
- Le Chen
- College of Civil and Transportation Engineering, Hohai University, Nanjing, 210098, PR China
| | - Wei Zhu
- College of Environment, Hohai University, Nanjing, 210098, PR China.
| | - Nai-Xi Lin
- College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Biao Mu
- College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Xi-Hui Fan
- College of Civil and Transportation Engineering, Hohai University, Nanjing, 210098, PR China
| | - Chen-Yu Wang
- College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Huai-Min Chen
- College of Environment, Hohai University, Nanjing, 210098, PR China
| | - Jun Zhong
- College of Environment, Hohai University, Nanjing, 210098, PR China
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Tawabini BS, Nielsen OJ, Sølling TI. Theoretical study of hydroxyl radical (OH˙) induced decomposition of tert-butyl methyl ether (MTBE). Environ Sci Process Impacts 2020; 22:1037-1044. [PMID: 32119021 DOI: 10.1039/c9em00588a] [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
We have characterized the various pathways for OH radical (OH˙) induced decomposition of tert-butyl methyl ether (MTBE) and found an oxidative pathway that leads to complete degradation under the prerequisite that OH radicals are present in excess. A simple polarizable continuum model is used to predict the behavior in an aqueous medium and the behavior is unchanged compared to that in the gas phase. The computational study has also revealed some of the fundamental aspects of hydrogen transfer from asymmetric ethers; the ˙OH assisted hydrogen abstraction has a barrier when the reaction takes place at a distance from the heteroatom, that is, at the tert-butyl group, whereas hydrogen abstraction from the methyl group proceeds without a barrier. The addition of ˙OH to (CH3)3COCH2˙ also proceeds without a barrier, and so does hydrogen abstraction from the resulting adduct ((CH3)3COCH2OH) to form (CH3)3COCH(OH)˙. However, a barrier is yet again found in the hydrogen abstraction from the latter to form (CH3)3COCH[double bond, length as m-dash]O and yet again in the formation of the formyl radical (CH3)3COC[double bond, length as m-dash]O˙ by hydrogen abstraction. The latter is the last step before the final stage of complete oxidation of MTBE to form CO2.
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Affiliation(s)
- Bassam S Tawabini
- Department of Geosciences, College of Petroleum & Geosciences, King Fahad University of Petroleum & Minerals (KFUPM), Dhahran 31261, Saudi Arabia
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d’Errico G, Aloj V, Ventorino V, Bottiglieri A, Comite E, Ritieni A, Marra R, Bolletti Censi S, Flematti GR, Pepe O, Vinale F. Methyl t-butyl ether-degrading bacteria for bioremediation and biocontrol purposes. PLoS One 2020; 15:e0228936. [PMID: 32084150 PMCID: PMC7034917 DOI: 10.1371/journal.pone.0228936] [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] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Accepted: 01/27/2020] [Indexed: 11/27/2022] Open
Abstract
A total of fifteen potential methyl t-butyl ether (MtBE)-degrading bacterial strains were isolated from contaminated soil. They have been identified as belonging to the genera Bacillus, Pseudomonas, Kocuria, Janibacter, Starkeya, Bosea, Mycolicibacterium, and Rhodovarius. Bacillus aryabhattai R1B, S. novella R8b, and M. mucogenicum R8i were able to grow using MtBE as carbon source, exhibiting different growth behavior and contaminant degradation ability. Their biocontrol ability was tested against various fungal pathogens. Both S. novella R8b and B. aryabhattai were effective in reducing the development of necrotic areas on leaves within 48 hours from Botritys cinerea and Alternaria alternata inoculation. Whereas, M. mucogenicum effectively controlled B. cinerea after 72 hours. Similar results were achieved using Pythium ultimum, in which the application of isolated bacteria increased seed germination. Only M. mucogenicum elicited tomato plants resistance against B. cinerea. This is the first report describing the occurrence of bioremediation and biocontrol activities in M. mucogenicum, B. aryabhattai and S. novella species. The production of maculosin and its antibiotic activity against Rhizoctonia solani has been reported for first time from S. novella. Our results highlight the importance of multidisciplinary approaches to achieve a consistent selection of bacterial strains useful for plant protection and bioremediation purposes.
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Affiliation(s)
- Giada d’Errico
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Veronica Aloj
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Valeria Ventorino
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Assunta Bottiglieri
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Ernesto Comite
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Alberto Ritieni
- University of Naples Federico II, Department of Pharmacy, Naples, Italy
| | - Roberta Marra
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | | | - Gavin R. Flematti
- School of Molecular Sciences, The University of Western Australia, Crawley, WA, Australia
| | - Olimpia Pepe
- University of Naples Federico II, Department of Agricultural Sciences, Portici (NA), Italy
| | - Francesco Vinale
- University of Naples Federico II, Department of Veterinary Medicine and Animal Production, Naples, Italy
- National Research Council, Institute for Sustainable Plant Protection, Portici (NA), Italy
- * E-mail:
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7
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Darabi J, Ghiasvand A. Chromium-Based Polypyrrole/MIL-101 Nanocomposite as an Effective Sorbent for Headspace Microextraction of Methyl tert-Butyl Ether in Soil Samples. Molecules 2020; 25:molecules25030644. [PMID: 32028571 PMCID: PMC7037173 DOI: 10.3390/molecules25030644] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2020] [Revised: 01/31/2020] [Accepted: 01/31/2020] [Indexed: 11/16/2022] Open
Abstract
The performance of headspace solid-phase microextraction (HS-SPME) was upgraded by easy and low-cost preparation of a new nanocomposite fiber. A polypyrrole/chromium-based metal–organic framework, PPy@MIL-101(Cr), nanocomposite was electrochemically synthesized and simultaneously coated on a steel wire as a microextraction sorbent. The morphology and chemical structure of the prepared nanocomposite was characterized by Fourier-transform infrared spectrometry (FT-IR), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX) techniques. The microsorbent was used for sampling of methyl-tert-butyl ether (MTBE) in solid samples, through an HS-SPME sampling strategy, followed by GC-FID measurement. The optimal experimental conditions, including extraction temperature, extraction time, and GC desorption conditions, were evaluated and optimized. The proposed procedure showed good sensitivity (limit of detection was 0.01 ng·g−1) and precision (relative standard deviation was 8.4% for six replicated analyses). The calibration curve was linear over the range of 5–40,000 ng·g−1, with a correlation coefficient of 0.994. The limit of quantification was 0.4 ng·g−1. The fabricated fiber exhibited good repeatability and reproducibility for the sampling of MTBE, with average recovery values of 88–114%. The intra-fiber and inter-fiber precisions were found to be 8.4% and 19%, respectively. The results demonstrated the superiority of the PPy@MIL-101(Cr)-coated fiber in comparison with handmade (polypyrrole, PPY) and commercial fibers (polyacrylate, PA; polydimethylsiloxane, PDMS; and divinylbenzene/carboxen/polydimethylsiloxane, DVB/CAR/PDMS) for the analysis of solid samples. The developed method was successfully employed for the analysis of MTBE in different soil samples contaminated by oil products.
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8
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Pongkua W, Dolphen R, Thiravetyan P. Bioremediation of gaseous methyl tert-butyl ether by combination of sulfuric acid modified bagasse activated carbon-bone biochar beads and Acinetobacter indicus screened from petroleum contaminated soil. Chemosphere 2020; 239:124724. [PMID: 31505447 DOI: 10.1016/j.chemosphere.2019.124724] [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: 03/07/2019] [Revised: 08/28/2019] [Accepted: 08/30/2019] [Indexed: 06/10/2023]
Abstract
Combination of sulfuric acid modified bagasse activated carbon-bone biochar beads and Acinetobacter indicus screened from petroleum contaminated soil was the best condition for gaseous methyl tert-butyl ether (MTBE) removal. It was found that H2SO4 modified bagasse AC in powder form had higher adsorption capacity (989.33 mg g-1) than that in bead form (1.94 mg g-1). In addition, bone biochar in powder form (3.51 mg g-1) also had higher adsorption capacity than that in bead form (1.63 mg g-1). This was the fact that material beads contained high moisture content that inhibited the penetration of gaseous MTBE into the material. And a mixed material of H2SO4 modified bagasse AC-bone biochar beads had the highest adsorption capacity (2.22 mg g-1) compared to individual H2SO4 modified bagasse AC beads (1.94 mg g-1) and bone biochar beads (1.63 mg g-1) due to a mixed material had more rough surface and high surface area on its material. So, gaseous MTBE can penetrate through this material more easily. Although the maximum adsorption capacity of H2SO4 modified bagasse AC in powder form was the highest but microorganism cannot sustain and survive in this form for a long time. Therefore, the material beads were more suitable for microorganism to grow and degrade gaseous MTBE. Microorganism can degrade MTBE and caused no secondary wastes. Moreover, A. indicus was a novel strain for MTBE removal that has not been previously reported. Therefore, a combination of A. indicus-mixed material beads was a good choice for MTBE removal in a biofilter system.
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Affiliation(s)
- Waleeporn Pongkua
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Rujira Dolphen
- Pilot Plant Development and Training Institute, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand
| | - Paitip Thiravetyan
- School of Bioresources and Technology, King Mongkut's University of Technology Thonburi, Bangkok, 10150, Thailand.
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9
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McCullough BS, Batsomboon P, Hutchinson KB, Dudley GB, Barrios AM. Synthesis and PTP Inhibitory Activity of Illudalic Acid and Its Methyl Ether, with Insights into Selectivity for LAR PTP over Other Tyrosine Phosphatases under Physiologically Relevant Conditions. J Nat Prod 2019; 82:3386-3393. [PMID: 31809044 DOI: 10.1021/acs.jnatprod.9b00663] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
The protein tyrosine phosphatase (PTP) family of enzymes includes many attractive therapeutic targets, such as those in the leukocyte common antigen-related (LAR) subfamily of receptor PTPs. Synthesis and PTP inhibitory activity of illudalic acid and its methyl ether are described, with a focus on selective inhibition of LAR PTP relative to a small collection of other representative PTPs. The synthesis comprises 16 steps and provides illudalic acid in up to 12% overall yield from neopentylene-fused benzoate 1 (20 steps from commercial materials). Illudalic acid dose-dependently (measured IC50 = 2.1 ± 0.2 μM) and time-dependently inhibits LAR consistent with previous reports of covalent binding. The kinetics of LAR inhibition by illudalic acid are consistent with a two-step mechanism in which the inhibitor and enzyme first interact noncovalently (KI = 130 ± 50 μM), followed by covalent ligation at a rate kinact = 1.3 ± 0.4 min-1. The kinact/KI ratio of 104 corresponds to a t∞1/2 of 0.5 min, as discussed herein. The phenol methyl ether of illudalic acid was found to be less potent in our dose-response assays (measured IC50 = 55 ± 6 μM) but more selective for LAR, with a weaker initial noncovalent interaction and faster covalent ligation of LAR as compared to illudalic acid itself. A truncated analogue of illudalic acid that lacks the neopentylene ring fusion was found to be devoid of significant activity under our assay conditions, in contrast to previous reports. These observations collectively help inform further development of illudalic acid analogues as potent and selective inhibitors of the LAR subfamily of tyrosine phosphatases.
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Affiliation(s)
- Brandon S McCullough
- Department of Medicinal Chemistry , University of Utah , Salt Lake City , Utah 84112 , United States
| | - Paratchata Batsomboon
- C. Eugene Bennett Department of Chemistry , West Virginia University , Morgantown , West Virginia 26506 , United States
| | - Kacey B Hutchinson
- Department of Medicinal Chemistry , University of Utah , Salt Lake City , Utah 84112 , United States
| | - Gregory B Dudley
- C. Eugene Bennett Department of Chemistry , West Virginia University , Morgantown , West Virginia 26506 , United States
| | - Amy M Barrios
- Department of Medicinal Chemistry , University of Utah , Salt Lake City , Utah 84112 , United States
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Kucharzyk KH, Rectanus HV, Bartling CM, Rosansky S, Minard-Smith A, Mullins LA, Neil K. Use of omic tools to assess methyl tert-butyl ether (MTBE) degradation in groundwater. J Hazard Mater 2019; 378:120618. [PMID: 31301927 DOI: 10.1016/j.jhazmat.2019.05.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [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: 03/13/2019] [Revised: 05/03/2019] [Accepted: 05/05/2019] [Indexed: 06/10/2023]
Abstract
This study employed innovative technologies to evaluate multiple lines of evidence for natural attenuation (NA) of methyl tertiary-butyl ether (MTBE) in groundwater at the 22 Area of Marine Corps Base (MCB) Camp Pendleton after decommissioning of a biobarrier system. For comparison, data from the 13 Area Gas Station where active treatment of MTBE is occurring was used to evaluate the effectiveness of omic techniques in assessing biodegradation. Overall, the 22 Area Gas Station appeared to be anoxic. MTBE was detected in large portion of the plume. In comparison, concentrations of MTBE at the 13 Area Gas Station were much higher (42,000 μg/L to 2800 μg/L); however, none of the oxygenates were detected. Metagenomic analysis of the indigenous groundwater microbial community revealed the presence of bacterial strains known to aerobically and anaerobically degrade MTBE at both sites. While proteomic analysis at the 22 Area Gas Station showed the presence of proteins of MTBE degrading microorganisms, the MTBE degradative proteins were only found at the 13 Area Gas Station. Taken together, these results provide evidence for previous NA of MTBE in the groundwater at 22 Area Gas Station and demonstrate the effectiveness of innovative-omic technologies to assist monitored NA assessments.
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Affiliation(s)
| | | | | | - Steve Rosansky
- Battelle Memorial Institute, Columbus, OH, United States
| | | | | | - Kenda Neil
- Naval Facilities Engineering Command (NAVFAC) Engineering and Expeditionary Warfare Center (EXWC), Port Huaneme, CA, United States
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11
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Davies SG, Fletcher AM, Roberts PM, Thomson JE, Yeung A. N-Acetylcolchinol Methyl Ether (a Natural Product); Suhailamine (a Phantom Natural Product). J Nat Prod 2019; 82:2659-2663. [PMID: 31486642 DOI: 10.1021/acs.jnatprod.9b00595] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [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 reported characterization data for the allocolchicinoid alkaloid suhailamine, isolated from Colchicum decaisnei and known to have an erroneous structure, have been reanalyzed. This analysis has led to the current proposal that suhailamine has the same structure as N-acetylcolchinol methyl ether (NCME), an assertion that is supported by comparison with previously reported data for NCME. Suhailamine is therefore a phantom natural product, while NCME represents a naturally occurring allocolchicinoid rather than a purely synthetic entity.
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Affiliation(s)
- Stephen G Davies
- Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K
| | - Ai M Fletcher
- Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K
| | - Paul M Roberts
- Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K
| | - James E Thomson
- Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K
| | - Angus Yeung
- Department of Chemistry, Chemistry Research Laboratory , University of Oxford , Mansfield Road , Oxford OX1 3TA , U.K
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12
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Jia X, Yin S, Xu J, Li N, Ren M, Qin Y, Zhou J, Wei Y, Guo Y, Gao M, Yu Y, Wang B, Li Z. An efficient method to simultaneously analyze multi-class organic pollutants in human serum. Environ Pollut 2019; 251:400-406. [PMID: 31100571 DOI: 10.1016/j.envpol.2019.05.008] [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: 11/28/2018] [Revised: 04/30/2019] [Accepted: 05/02/2019] [Indexed: 06/09/2023]
Abstract
The degree of population exposure to various organic pollutants (OPs), including polycyclic aromatic hydrocarbons, organochlorinated pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers, can be determined by measuring their concentrations in human serum. However, performing large-scale measurements with such a variety of compounds in serum is challenging in terms of efficiency and cost. We describe herein the development of a high-efficiency extraction and sample cleanup protocol for simultaneous and quantitative analyses of OPs using gas chromatography-mass spectrometry. OPs, together with crude lipid impurities, were extracted from human serum with a mixture of n-hexane and methyl tert-butyl ether. A disperse sorbent composed of primary secondary amine and C18 (PSA/C18) was used to roughly remove co-extracted impurities. A combined column of neutral silica gel and neutral alumina oxide (AlO/SiG) was then used for deep cleanup. For the removal of impurities, the overall performance of our protocol for the analysis of OPs in serum was comparable to that of traditional gel permeation chromatography (GPC) and dramatically better than that of PSA/C18, which is a frequently used QuEChERS (quick, easy, cheap, effective, rugged, safe) based method. While both the proposed protocol and GPC yielded recoveries of 80%-110% for four classes of OPs, our protocol consumed about 10 times less solvent, resulting in lower experimental expenses and a lower risk of contamination from residual OPs in the solvent and other supplies. In contrast to GPC, our protocol also permits efficient batch processing of serum samples, allowing for large sample sizes such as those encountered in epidemiological studies.
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Affiliation(s)
- Xiaoqian Jia
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Shengju Yin
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Junhui Xu
- Department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Nan Li
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Mengyuan Ren
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Yanan Qin
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
| | - Jiansuo Zhou
- Department of Laboratory Medicine, Peking University Third Hospital, Beijing, 100191, PR China
| | - Yuan Wei
- Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, 100191, PR China
| | - Yunhe Guo
- School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Miaomiao Gao
- School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Yanxin Yu
- School of Environment, Beijing Normal University, Beijing, 100875, PR China
| | - Bin Wang
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China.
| | - Zhiwen Li
- Institute of Reproductive and Child Health, Peking University/ Key Laboratory of Reproductive Health, National Health Commission of the People's Republic of China, Beijing, 100191, PR China; Department of Epidemiology and Biostatistics, School of Public Health, Peking University, Beijing, 100191, PR China
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13
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Chaurasiya ND, Zhao J, Pandey P, Doerksen RJ, Muhammad I, Tekwani BL. Selective Inhibition of Human Monoamine Oxidase B by Acacetin 7-Methyl Ether Isolated from Turnera diffusa (Damiana). Molecules 2019; 24:molecules24040810. [PMID: 30813423 PMCID: PMC6412401 DOI: 10.3390/molecules24040810] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [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: 12/29/2018] [Revised: 02/18/2019] [Accepted: 02/19/2019] [Indexed: 12/15/2022] Open
Abstract
The investigation of the constituents that were isolated from Turnera diffusa (damiana) for their inhibitory activities against recombinant human monoamine oxidases (MAO-A and MAO-B) in vitro identified acacetin 7-methyl ether as a potent selective inhibitor of MAO-B (IC50 = 198 nM). Acacetin 7-methyl ether (also known as 5-hydroxy-4′, 7-dimethoxyflavone) is a naturally occurring flavone that is present in many plants and vegetables. Acacetin 7-methyl ether was four-fold less potent as an inhibitor of MAO-B when compared to acacetin (IC50 = 50 nM). However, acacetin 7-methyl ether was >500-fold selective against MAO-B over MAO-A as compared to only two-fold selectivity shown by acacetin. Even though the IC50 for inhibition of MAO-B by acacetin 7-methyl ether was ~four-fold higher than that of the standard drug deprenyl (i.e., SelegilineTM or ZelaparTM, a selective MAO-B inhibitor), acacetin 7-methyl ether’s selectivity for MAO-B over MAO-A inhibition was greater than that of deprenyl (>500- vs. 450-fold). The binding of acacetin 7-methyl ether to MAO-B was reversible and time-independent, as revealed by enzyme-inhibitor complex equilibrium dialysis assays. The investigation on the enzyme inhibition-kinetics analysis with varying concentrations of acacetin 7-methyl ether and the substrate (kynuramine) suggested a competitive mechanism of inhibition of MAO-B by acacetin 7-methyl ether with Ki value of 45 nM. The docking scores and binding-free energies of acacetin 7-methyl ether to the X-ray crystal structures of MAO-A and MAO-B confirmed the selectivity of binding of this molecule to MAO-B over MAO-A. In addition, molecular dynamics results also revealed that acacetin 7-methyl ether formed a stable and strong complex with MAO-B. The selective inhibition of MAO-B suggests further investigations on acacetin 7-methyl as a potential new drug lead for the treatment of neurodegenerative disorders, including Parkinson’s disease.
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Affiliation(s)
- Narayan D Chaurasiya
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
| | - Jianping Zhao
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
| | - Pankaj Pandey
- Department of BioMolecular Sciences, Division of Medicinal Chemistry and Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
| | - Robert J Doerksen
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
- Department of BioMolecular Sciences, Division of Medicinal Chemistry and Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
| | - Ilias Muhammad
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
| | - Babu L Tekwani
- National Center for Natural Products Research, Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
- Department of BioMolecular Sciences, Division of Medicinal Chemistry and Research Institute of Pharmaceutical Sciences, School of Pharmacy, The University of Mississippi, Oxford, MS 38677, USA.
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14
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Purswani J, Guisado IM, Coello-Cabezas J, González-López J, Pozo C. Social microbial inocula confer functional stability in a methyl tert-butyl ether extractive membrane biofilm bioreactor. Environ Pollut 2019; 244:855-860. [PMID: 30390459 DOI: 10.1016/j.envpol.2018.10.100] [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] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 10/19/2018] [Accepted: 10/24/2018] [Indexed: 06/08/2023]
Abstract
Methyl tert-butyl ether (MTBE) degradation technologies based on two-phase partitioning systems such as extractive membrane biofilm reactors (EMBFR) permit separation of biological and contaminant compartments, thus allowing optimization of the biological section. In this study, we set-up an EMBFR with three MTBE-degrading and cooperating strains (termed social biofilm: Agrobacterium sp. MS2, Paenibacillus etheri SH7T and Rhodococcus ruber EE6). The removal efficiency of the social-biofilm EMBFR was 80%, and functional stability was observed in the reactor, i.e. more efficient than previous studies (single-strain inoculated EMBFR, <50% removal efficiency and unstable function). Metabolite tert-butyl alcohol was not observed, and the EC50 values were higher than those observed in single-strain EMBFRs. Comparative analysis of the MTBE enzymatic pathway and the social-biofilm was performed, where the mechanism of cooperation observed within the social-biofilm is likely due to enzymatic redundancy. Functional outcomes were equal to previous batch tests, hence 100% scalability was obtained. Overall, higher functional and stability outcomes are obtained with the use of the social-biofilm in an MTBE-EMBFR.
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Affiliation(s)
- Jessica Purswani
- Environmental Microbiology Group, Institute of Water Research, University of Granada, Granada, Spain; Department of Microbiology, University of Granada, Granada, Spain.
| | - Isabel M Guisado
- Environmental Microbiology Group, Institute of Water Research, University of Granada, Granada, Spain; Department of Microbiology, University of Granada, Granada, Spain
| | - Julio Coello-Cabezas
- Environmental Microbiology Group, Institute of Water Research, University of Granada, Granada, Spain
| | - Jesús González-López
- Environmental Microbiology Group, Institute of Water Research, University of Granada, Granada, Spain; Department of Microbiology, University of Granada, Granada, Spain
| | - Clementina Pozo
- Environmental Microbiology Group, Institute of Water Research, University of Granada, Granada, Spain; Department of Microbiology, University of Granada, Granada, Spain
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15
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Mukhtar YM, Adu-Frimpong M, Xu X, Yu J. Biochemical significance of limonene and its metabolites: future prospects for designing and developing highly potent anticancer drugs. Biosci Rep 2018; 38:BSR20181253. [PMID: 30287506 PMCID: PMC6239267 DOI: 10.1042/bsr20181253] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [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: 07/26/2018] [Revised: 09/17/2018] [Accepted: 09/27/2018] [Indexed: 01/04/2023] Open
Abstract
Monocyclic monoterpenes have been recognized as useful pharmacological ingredients due to their ability to treat numerous diseases. Limonene and perillyl alcohol as well as their metabolites (especially perillic acid and its methyl ester) possess bioactivities such as antitumor, antiviral, anti-inflammatory, and antibacterial agents. These therapeutic properties have been well documented. Based on the aforementioned biological properties of limonene and its metabolites, their structural modification and development into effective drugs could be rewarding. However, utilization of these monocyclic monoterpenes as scaffolds for the design and developments of more effective chemoprotective agents has not received the needed attention by medicinal scientists. Recently, some derivatives of limonene metabolites have been synthesized. Nonetheless, there have been no thorough studies on their pharmacokinetic and pharmacodynamic properties as well as their inhibition against isoprenylation enzymes. In this review, recent research progress in the biochemical significance of limonene and its metabolites was summarized with emphasis on their antitumor effects. Future prospects of these bioactive monoterpenes for drug design and development are also highlighted.
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Affiliation(s)
- Yusif M Mukhtar
- Department of Pharmaceutics and Tissue Engineering, School of pharmacy, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu Province, P.R. China
| | - Michael Adu-Frimpong
- Department of Pharmaceutics and Tissue Engineering, School of pharmacy, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu Province, P.R. China
- Department of Basic and Biomedical Sciences, College of Health and Well-Being, P. O. Box 9, Kintampo, Ghana
| | - Ximing Xu
- Department of Pharmaceutics and Tissue Engineering, School of pharmacy, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu Province, P.R. China
| | - Jiangnan Yu
- Department of Pharmaceutics and Tissue Engineering, School of pharmacy, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013, Jiangsu Province, P.R. China
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16
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Varuvel EG, Sonthalia A, Subramanian T, Aloui F. NOx-smoke trade-off characteristics of minor vegetable oil blends synergy with oxygenate in a commercial CI engine. Environ Sci Pollut Res Int 2018; 25:35715-35724. [PMID: 30357667 DOI: 10.1007/s11356-018-3484-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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: 05/06/2018] [Accepted: 10/16/2018] [Indexed: 06/08/2023]
Abstract
The present study investigates the effect of blending oxygenate namely diethylene glycol dimethyl ether (diglyme) with minor vegetable oil namely rubber seed oil (RSO), babassu oil (BSO), and their blends in various proportions (R75B25, R50B50, and R25B75) on NOx-smoke trade-off and other engine characteristics. The tests were conducted on a commercial twin cylinder compression-ignition (CI) engine commonly used in tractors. The potential of the blends with diglyme is assessed based on performance, emission, and combustion characteristics of the engine at different load conditions. The tests were conducted at a constant speed of 1500 rpm maintaining the original injection timing and pressure. Compared to diesel, RSO, and BSO, and their blends exhibited inferior combustion due to poor physical properties like high viscosity and density. This resulted in a lower brake thermal efficiency with increase in HC, CO, and smoke emissions compared to diesel at all the load conditions. The augmented effect is observed with increase in BSO proportion for the blends and neat BSO. The poor combustion of minor vegetable oil and its blends lead to lower NOx emission as a result of lower in-cylinder temperature. To improve the performance and NOx-smoke trade-off, diglyme (DGM) was added with all the test fuels with the optimum share of 20% (by volume). Addition of DGM, increased brake thermal efficiency by 2-7% for all the test fuels due to improved combustion as a result of additional fuel bound oxygen in DGM and improved fuel blend properties. DGM addition reduced smoke, HC, and CO emission drastically with a slight increase in NOx emission compared to minor vegetable oil blends. The study shows that addition of DGM showed a promising note in NOx-smoke trade-off without affecting the other engine parameters.
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Affiliation(s)
- Edwin Geo Varuvel
- Department of Automobile Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India
| | - Ankit Sonthalia
- Department of Automobile Engineering, SRM Institute of Science and Technology, NCR Campus, Modi Nagar, 201204, India
| | - Thiyagarajan Subramanian
- Department of Automobile Engineering, SRM Institute of Science and Technology, Kattankulathur, Tamil Nadu, 603203, India.
| | - Fethi Aloui
- Department of Mechanical Engineering, University of Valenciennes (UVHC), Campus Mont-Houy, LAMIH UMR CNRS 8201, F-59313, Valenciennes Cedex 9, France
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17
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Bragadeshwaran A, Kasianantham N, Ballusamy S, Tarun KR, Dharmaraj AP, Kaisan MU. Experimental study of methyl tert-butyl ether as an oxygenated additive in diesel and Calophyllum inophyllum methyl ester blended fuel in CI engine. Environ Sci Pollut Res Int 2018; 25:33573-33590. [PMID: 30269280 DOI: 10.1007/s11356-018-3318-y] [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: 04/24/2018] [Accepted: 09/24/2018] [Indexed: 06/08/2023]
Abstract
This work presents the effect of the ternary oxygenated additive on diesel biodiesel blended fuel to evaluate the engine characteristics. The Calophyllum inophyllum trees being abundant in India can lessen the dependence on petroleum imports to a specific extent. Methyl tertiary butyl ether is used as an oxygenated additive for the ternary blends preparation as 5-20% by volume. Seven blends of neat baseline diesel, biodiesel (Calophyllum inophyllum Methyl Ester), a blend of diesel (50%)-biodiesel (50%), a blend of diesel (50%)-biodiesel-methyl tert-butyl ether (5, 10, 15, and 20%) are prepared which are tested on a single cylinder, constant speed diesel engine. The experimental results were revealed that the replacement of biodiesel by MTBE has shown a slight reduction in brake thermal efficiency with a slight increase in brake-specific fuel consumption. Further, the MTBE addition in ternary blends reduced the unburned hydrocarbon, CO, and NOx by 63.9, 6.4, and 3.37% respectively. In addition, the carbon dioxide emission is almost similar to diesel fuel at a higher addition of MTBE with diesel-biodiesel blend. In the combustion point of view, the addition of 5% MTBE resulted in 3.49 and 5.1% reduction of peak pressure and heat release rate are observed as compared to diesel fuel. Critical analysis in combustion aspects is also carried out and it is witnessed with prolonged ignition delay during MTBE addition with diesel-biodiesel blends.
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Affiliation(s)
| | | | - Saravanan Ballusamy
- Department of Mechanical and Aerospace Engineering, Indian Institute of Technology (IIT), Hyderabad, India
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18
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Liadi MA, Tawabini B, Shawabkeh R, Jarrah N, Oyehan TA, Shaibani A, Makkawi M. Treating MTBE-contaminated water using sewage sludge-derived activated carbon. Environ Sci Pollut Res Int 2018; 25:29397-29407. [PMID: 30128970 DOI: 10.1007/s11356-018-2737-0] [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: 04/15/2018] [Accepted: 07/06/2018] [Indexed: 06/08/2023]
Abstract
In this study, sewage sludge-derived activated carbon (SDAC) was synthesized, characterized, and tested for its potential as an adsorbent of methyl tert-butyl ether (MTBE). The SDAC was produced by activating the sludge with zinc chloride and subsequently subjected to various ranges of pyrolytic temperatures. It was then characterized using SEM/EDX, BET, and TGA. The SEM-EDX analyses showed that impurities like Fe, Al, Mg, Mn, Ca, and Na of the raw sludge were removed by the higher pyrolytic temperature and acid-washing procedures. TGA showed the thermal stability of the produced material. Results of the BET revealed a significant increase in surface area of the sludge from 1.5 m2/g to 385 m2/g after acid washing. The MTBE removal efficiency of 70% was achieved after 60 min with 2 g/L of SDAC at pH 6, and initial MTBE concentration of 1 ppm. The adsorption kinetics of SDAC fitted into pseudo-second-order reactions. This work demonstrated a beneficial use of a bio-waste material (sewage sludge) in water treatment technologies.
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Affiliation(s)
- Musiliu A Liadi
- Geosciences Department, King Fahd University of Petroleum and Minerals (KFUPM), P.O. Box 189, Dhahran, 31261, Saudi Arabia
| | - Bassam Tawabini
- Geosciences Department, King Fahd University of Petroleum and Minerals (KFUPM), P.O. Box 189, Dhahran, 31261, Saudi Arabia.
| | - Reyad Shawabkeh
- Chemical Engineering Department, University of Jordan, Amman, Jordan
| | - Nabil Jarrah
- Chemical Engineering Department, Mutah University, Karak, Jordan
| | - Tajudeen A Oyehan
- Geosciences Department, King Fahd University of Petroleum and Minerals (KFUPM), P.O. Box 189, Dhahran, 31261, Saudi Arabia
| | - Abdulaziz Shaibani
- Geosciences Department, King Fahd University of Petroleum and Minerals (KFUPM), P.O. Box 189, Dhahran, 31261, Saudi Arabia
| | - Mohammed Makkawi
- Geosciences Department, King Fahd University of Petroleum and Minerals (KFUPM), P.O. Box 189, Dhahran, 31261, Saudi Arabia
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Thakkar BS, Svendsen JSM, Engh RA. Density Functional Studies on Secondary Amides: Role of Steric Factors in Cis/Trans Isomerization. Molecules 2018; 23:molecules23102455. [PMID: 30257481 PMCID: PMC6222500 DOI: 10.3390/molecules23102455] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 09/21/2018] [Accepted: 09/21/2018] [Indexed: 11/16/2022] Open
Abstract
Cis/trans isomerization of amide bonds is a key step in a wide range of biological and synthetic processes. Occurring through C-N amide bond rotation, it also coincides with the activation of amides in enzymatic hydrolysis. In recently described QM studies of cis/trans isomerization in secondary amides using density functional methods, we highlighted that a peptidic prototype, such as glycylglycine methyl ester, can suitably represent the isomerization and complexities arising out of a larger molecular backbone, and can serve as the primary scaffold for model structures with different substitution patterns in order to assess and compare the steric effect of the substitution patterns. Here, we describe our theoretical assessment of such steric effects using tert-butyl as a representative bulky substitution. We analyze the geometries and relative stabilities of both trans and cis isomers, and effects on the cis/trans isomerization barrier. We also use the additivity principle to calculate absolute steric effects with a gradual increase in bulk. The study establishes that bulky substitutions significantly destabilize cis isomers and also increases the isomerization barrier, thereby synergistically hindering the cis/trans isomerization of secondary amides. These results provide a basis for the rationalization of kinetic and thermodynamic properties of peptides with potential applications in synthetic and medicinal chemistry.
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Affiliation(s)
- Balmukund S Thakkar
- Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway.
| | | | - Richard A Engh
- Department of Chemistry, UiT The Arctic University of Norway, N-9037 Tromsø, Norway.
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20
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Abstract
Shotgun lipidomics offers fast and reproducible identification and quantification of lipids in clinical samples. Lipid extraction procedures based on the methyl tert-butyl protocol are well established for performing shotgun lipidomics in biomedical research. Here, we describe a shotgun lipidomics workflow that is well suited for the analysis of clinical samples such as tissue samples, blood plasma, and peripheral blood mononuclear cells.
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Affiliation(s)
- Lars F Eggers
- Division of Bioanalytical Chemistry, Research Center Borstel, Borstel, 23845, Germany
| | - Dominik Schwudke
- Division of Bioanalytical Chemistry, Research Center Borstel, Borstel, 23845, Germany.
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21
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Catizzone E, Bonura G, Migliori M, Frusteri F, Giordano G. CO₂ Recycling to Dimethyl Ether: State-of-the-Art and Perspectives. Molecules 2017; 23:E31. [PMID: 29295541 PMCID: PMC5943932 DOI: 10.3390/molecules23010031] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [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: 11/13/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 12/02/2022] Open
Abstract
This review reports recent achievements in dimethyl ether (DME) synthesis via CO₂ hydrogenation. This gas-phase process could be considered as a promising alternative for carbon dioxide recycling toward a (bio)fuel as DME. In this view, the production of DME from catalytic hydrogenation of CO₂ appears as a technology able to face also the ever-increasing demand for alternative, environmentally-friendly fuels and energy carriers. Basic considerations on thermodynamic aspects controlling DME production from CO₂ are presented along with a survey of the most innovative catalytic systems developed in this field. During the last years, special attention has been paid to the role of zeolite-based catalysts, either in the methanol-to-DME dehydration step or in the one-pot CO₂-to-DME hydrogenation. Overall, the productivity of DME was shown to be dependent on several catalyst features, related not only to the metal-oxide phase-responsible for CO₂ activation/hydrogenation-but also to specific properties of the zeolites (i.e., topology, porosity, specific surface area, acidity, interaction with active metals, distributions of metal particles, …) influencing activity and stability of hybridized bifunctional heterogeneous catalysts. All these aspects are discussed in details, summarizing recent achievements in this research field.
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Affiliation(s)
- Enrico Catizzone
- Department of Environmental and Chemical Engineering, University of Calabria, Via P. Bucci, 87036 Rende (CS), Italy.
| | - Giuseppe Bonura
- CNR-ITAE "Nicola Giordano", Via S. Lucia Sopra Contesse 5, 98126 Messina, Italy.
| | - Massimo Migliori
- Department of Environmental and Chemical Engineering, University of Calabria, Via P. Bucci, 87036 Rende (CS), Italy.
| | - Francesco Frusteri
- CNR-ITAE "Nicola Giordano", Via S. Lucia Sopra Contesse 5, 98126 Messina, Italy.
| | - Girolamo Giordano
- Department of Environmental and Chemical Engineering, University of Calabria, Via P. Bucci, 87036 Rende (CS), Italy.
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22
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Namdaung U, Athipornchai A, Khammee T, Kuno M, Suksamrarn S. 2-Arylbenzofurans from Artocarpus lakoocha and methyl ether analogs with potent cholinesterase inhibitory activity. Eur J Med Chem 2017; 143:1301-1311. [PMID: 29126732 DOI: 10.1016/j.ejmech.2017.10.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [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: 06/13/2017] [Revised: 07/30/2017] [Accepted: 10/09/2017] [Indexed: 11/19/2022]
Abstract
In vitro screening for acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of the Artocarpus lakoocha root-bark extracts revealed interesting results. Bioassay-guided fractionation resulted in the isolation of two new (1 and 2) and six known 2-arylbenzofurans 3-8, along with one stilbenoid 9 and one flavonoid 10. The structures of the isolated compounds were elucidated by UV, IR, 1D- and 2D-NMR and MS spectroscopic data analysis. Compounds 4, 6 and 7 exhibited more potent AChE inhibitory activity (IC50 = 0.87-1.10 μM) than the reference drug, galantamine. Compounds 4, 8 and 9 displayed greater BChE inhibition than the standard drug. The preferential inhibition of BChE over AChE indicated that 4 also showed a promising dual AChE and BChE inhibitor. The synthetic mono-methylated analogs 4a-c and 6a-b were found to be good BChE inhibitors with IC50 values ranging between 0.31 and 1.11 μM. Based on the docking studies, compounds 4 and 6 are well-fitted in the catalytic triad of AChE. Compounds 4 and 6 showed different binding orientations on BChE, and the most potent BChE inhibitor 4 occupied dual binding to both CAS and PAS more efficiently.
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Affiliation(s)
- Umalee Namdaung
- Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand
| | - Anan Athipornchai
- Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Burapha University, Chon-Buri 20131, Thailand
| | - Thongchai Khammee
- Department of Chemistry, Faculty of Science and Technology, Phranakhon Rajabhat University, Bangkok 10220, Thailand
| | - Mayuso Kuno
- Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand
| | - Sunit Suksamrarn
- Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand; Center of Excellence for Innovation in Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand.
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Bussy U, Chung-Davidson YW, Buchinger TJ, Li K, Li W. High-sensitivity determination of estrogens in fish plasma using chemical derivatization upstream UHPLC-MSMS. Steroids 2017; 123:13-19. [PMID: 28456451 DOI: 10.1016/j.steroids.2017.04.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 04/07/2017] [Accepted: 04/12/2017] [Indexed: 10/19/2022]
Abstract
This article describes the development and validation of a sensitive LC-MSMS method for determination of estrogen in fish plasma. Dansyl chloride derivatization of the phenol functional group in estrogen was used to enhance the response to atmospheric pressure ionization leading to improve the sensitivity. Individual 13C internal standards were selected after comparison with deuterated standards. Liquid-liquid extraction (ethyl acetate or methyl tert-butyl ether) and protein precipitation (acetonitrile, methanol or acetone) were compared for the extraction and clean-up of estrogens from fish plasma. Ethyl acetate was selected as the best alternative with recovery ranging from 61 to 96% and matrix effect ranging from 88 to 106%. Limits of quantification ranged from 0.5 to 1pg/mL showing a gain in sensitivity of 10,000 times over electrospray ionization of underivatized estrogens. Accuracy and precision were validated over three consecutive days and the method was applied to measure estrogen in sea lamprey (Petromyzon marinus) and lake trout (Salvelinus namaycush) plasma. Estrone and estriol were detected in fish below 1ng/mL in plasma, justifying the need of a highly sensitive LC-MSMS quantification method.
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Affiliation(s)
- Ugo Bussy
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA
| | - Yu-Wen Chung-Davidson
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA
| | - Tyler J Buchinger
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA
| | - Ke Li
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA
| | - Weiming Li
- Department of Fisheries and Wildlife, Michigan State University, Room 13 Natural Resources Building, 480 Wilson Road, East Lansing, MI 48824, USA.
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Belmessieri D, Gozlan C, Duclos MC, Molinier V, Aubry JM, Dumitrescu O, Lina G, Redl A, Duguet N, Lemaire M. Synthesis, surfactant properties and antimicrobial activities of methyl glycopyranoside ethers. Eur J Med Chem 2017; 128:98-106. [PMID: 28157594 DOI: 10.1016/j.ejmech.2017.01.038] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [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: 11/04/2016] [Revised: 12/20/2016] [Accepted: 01/23/2017] [Indexed: 11/30/2022]
Abstract
A series of amphiphilic methyl glucopyranoside ethers incorporating various alkyl chain lengths has been synthesized from commercially available methyl glucopyranosides following an acetalisation/hydrogenolysis sequence. The amphiphilic properties of ethers and acetal intermediates were evaluated. Both families exhibit excellent surfactant properties with a maximum efficiency obtained for compounds bearing a linear dodecyl chain (CMC = 0.012 mM, γsat. = 30 mN m-1). Antimicrobial activity studies revealed an efficient activity (0.03 < MIC < 0.12 mM) against Gram-positive bacteria such as Listeria monocytogenes, Enterococcus faecalis, Enterococcus faecium and Staphylococcus aureus. More importantly, these compounds were found to be active against multi-resistant strains such as vancomycin-, methicillin- and daptomycin-resistant strains. Finally, it was found that antimicrobial activities are closely related to physicochemical properties and are also influenced by the nature of the carbohydrate moiety.
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Affiliation(s)
- Dorine Belmessieri
- Univ Lyon, Université Claude Bernard Lyon1, CNRS, INSA-Lyon, CPE-Lyon, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, (ICBMS), UMR 5246, Equipe CAtalyse, SYnthèse et ENvironnement (CASYEN), 43 Boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France; Univ Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, CNRS, UMR5308, International Center for Infectiology Research (CIRI), Inserm U1111, 7 rue Guillaume Paradin, F-69008 Lyon, France; Centre National de Référence des Staphylocoques, 59 Boulevard Louis Pinel, F-69677 Bron Cedex, France
| | - Charlotte Gozlan
- Univ Lyon, Université Claude Bernard Lyon1, CNRS, INSA-Lyon, CPE-Lyon, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, (ICBMS), UMR 5246, Equipe CAtalyse, SYnthèse et ENvironnement (CASYEN), 43 Boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France; Tereos Syral SAS, Z.I et Portuaire, B.P.32, 67390 Marckolsheim, France
| | - Marie-Christine Duclos
- Univ Lyon, Université Claude Bernard Lyon1, CNRS, INSA-Lyon, CPE-Lyon, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, (ICBMS), UMR 5246, Equipe CAtalyse, SYnthèse et ENvironnement (CASYEN), 43 Boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France
| | - Valérie Molinier
- Univ. Lille, CNRS, ENSCL, UMR 8181, UCCS - Unité de Catalyse et Chimie du Solide, F-59000 Lille, Cité Scientifique, France
| | - Jean-Marie Aubry
- Univ. Lille, CNRS, ENSCL, UMR 8181, UCCS - Unité de Catalyse et Chimie du Solide, F-59000 Lille, Cité Scientifique, France
| | - Oana Dumitrescu
- Univ Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, CNRS, UMR5308, International Center for Infectiology Research (CIRI), Inserm U1111, 7 rue Guillaume Paradin, F-69008 Lyon, France; Centre National de Référence des Staphylocoques, 59 Boulevard Louis Pinel, F-69677 Bron Cedex, France
| | - Gérard Lina
- Univ Lyon, Université Claude Bernard Lyon 1, Ecole Normale Supérieure de Lyon, CNRS, UMR5308, International Center for Infectiology Research (CIRI), Inserm U1111, 7 rue Guillaume Paradin, F-69008 Lyon, France; Centre National de Référence des Staphylocoques, 59 Boulevard Louis Pinel, F-69677 Bron Cedex, France
| | - Andreas Redl
- Tereos Syral SAS, Z.I et Portuaire, B.P.32, 67390 Marckolsheim, France
| | - Nicolas Duguet
- Univ Lyon, Université Claude Bernard Lyon1, CNRS, INSA-Lyon, CPE-Lyon, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, (ICBMS), UMR 5246, Equipe CAtalyse, SYnthèse et ENvironnement (CASYEN), 43 Boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France.
| | - Marc Lemaire
- Univ Lyon, Université Claude Bernard Lyon1, CNRS, INSA-Lyon, CPE-Lyon, Institut de Chimie et Biochimie Moléculaires et Supramoléculaires, (ICBMS), UMR 5246, Equipe CAtalyse, SYnthèse et ENvironnement (CASYEN), 43 Boulevard du 11 novembre 1918, F-69622 Villeurbanne Cedex, France.
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Prapalert W, Santiarworn D, Liawruangrath S, Liawruangrath B. The Isolation of Lutein and Lutein 3'-methyl ether from Peristrophe lanceolaria. Nat Prod Commun 2016; 11:1793-1795. [PMID: 30508335] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023] Open
Abstract
Two carotenoids, lutein (1) and lutein 3'-methyl ether (2), have been isolated from the EtOAc fraction othe MeOH extract of Peristrophe lanceolaria, growing in Thailand. The structures of these compounds were elucidated from their ID and 2D NMR spectroscopic data and from comparisons made with the literature data. This is the first report of the isolation of lutein-3'-methyl ether as a natural product.
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Yang K, Dilthey BG, Gross RW. Shotgun Lipidomics Approach to Stabilize the Regiospecificity of Monoglycerides Using a Facile Low-Temperature Derivatization Enabling Their Definitive Identification and Quantitation. Anal Chem 2016; 88:9459-9468. [PMID: 27532157 PMCID: PMC5538723 DOI: 10.1021/acs.analchem.6b01862] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [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: 11/28/2022]
Abstract
Monoglycerides play a central role in lipid metabolism and are important signaling metabolites. Quantitative analysis of monoglyceride molecular species has remained challenging due to rapid isomerization via α-hydroxy acyl migration. Herein, we describe a shotgun lipidomics approach that utilizes a single-phase methyl tert-butyl ether extraction to minimize acyl migration, a facile low temperature diacetyl derivatization to stabilize regiospecificity, and tandem mass spectrometric analysis to identify and quantify regioisomers of monoglycerides in biological samples. The rapid and robust diacetyl derivatization at low temperatures (e.g., -20 °C, 30 min) prevents postextraction acyl migration and preserves regiospecificity of monoglyceride structural isomers. Furthermore, ionization of ammonium adducts of diacetyl monoglyceride derivatives in positive-ion mode markedly increases analytic sensitivity (low fmol/μL). Critically, diacetyl derivatization enables the differentiation of discrete monoglyceride regioisomers without chromatography through their distinct signature fragmentation patterns during collision induced dissociation. The application of this approach in the analysis of monoglycerides in multiple biologic tissues demonstrated diverse profiles of molecular species. Remarkably, the regiospecificity of individual monoglyceride molecular species is also diverse from tissue to tissue. Collectively, this developed approach enables the profiling, identification and quantitation of monoglyceride regioisomers directly from tissue extracts.
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Affiliation(s)
- Kui Yang
- Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Beverly G. Dilthey
- Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Richard W. Gross
- Division of Bioorganic Chemistry and Molecular Pharmacology, Departments of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, United States
- Developmental Biology, Washington University School of Medicine, St. Louis, Missouri 63110, United States
- Department of Chemistry, Washington University, St. Louis, Missouri 63130, United States
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27
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Smeds AI, Eklund PC, Willför SM. Chemical characterization of high-molar-mass fractions in a Norway spruce knotwood ethanol extract. Phytochemistry 2016; 130:207-17. [PMID: 27256310 DOI: 10.1016/j.phytochem.2016.05.006] [Citation(s) in RCA: 4] [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: 01/29/2016] [Revised: 04/21/2016] [Accepted: 05/18/2016] [Indexed: 05/23/2023]
Abstract
The low-molar-mass (LMM) fraction, only, i.e., the GC-eluting compounds, which are mainly lignans, has been characterized in Norway spruce knotwood hydrophilic extracts previously. Of this fraction, many lignans and sesquilignans and all GC peaks supposedly representing dilignans remain unidentified. In this work, dilignans and the GC non-eluting compounds (the high-molar mass fractions, HMM) were characterized in a 7-hydroxymatairesinol-reduced knotwood ethanol extract of Norway spruce by using several fractionation and analytical techniques. A methyl tert-butyl ether (MTBE) insoluble fraction of the extract contained mainly HMM material, of which the main part was shown to consist of lignan oligomers. The oligolignans (with a molar mass up to approximately 3700 Da) seemed to be linked by 55' bonds, some of them containing one or two guaiacylglycerol ether units linked to the lignan by βO4 or β5 bonds. Several oligolignans were identified or tentatively identified. The MTBE soluble fraction, which accounted for the major part (81%) of the extract, contained mainly LMM material (lignans, sesqui- and dilignans). The part of the HMM material in the MTBE soluble fraction that was easily isolable (2%) seemed to contain polymers of fatty acids and alcohols, resin acids, and sterols.
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Affiliation(s)
- Annika I Smeds
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, c/o Laboratory of Wood and Paper Chemistry, Porthansgatan 3-5, 20500 Turku, Finland.
| | - Patrik C Eklund
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, c/o Laboratory of Organic Chemistry, Biskopsgatan 8, 20500 Turku, Finland.
| | - Stefan M Willför
- Johan Gadolin Process Chemistry Centre, Åbo Akademi University, c/o Laboratory of Wood and Paper Chemistry, Porthansgatan 3-5, 20500 Turku, Finland.
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28
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Mehrata M, Moralejo C, Anderson WA. Adsorbent comparisons for anesthetic gas capture in hospital air emissions. J Environ Sci Health A Tox Hazard Subst Environ Eng 2016; 51:805-809. [PMID: 27222158 DOI: 10.1080/10934529.2016.1181438] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [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: 06/05/2023]
Abstract
For the development of emission control strategies, activated carbon, zeolite, molecular sieves, and a silica gel were tested for adsorption of the newer anesthetic gases isoflurane, sevoflurane, and desflurane from air. The activated carbon Norit GCA 48 was selected for the best performance, and adsorption isotherms at room temperature were developed for the three anesthetics. Equilibrium capacities for this carbon were in the range of 500 to 1,000 mg g(-1) for these anesthetics at partial pressures ranging from 5 to 45 Torr, with the most volatile compound (desflurane) showing the least favorable adsorption. Activated carbons are therefore suggested for use as effective adsorbents in emission control of these anesthetic gases from hospitals.
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Affiliation(s)
- Mina Mehrata
- a Department of Chemical Engineering , University of Waterloo , Waterloo , Ontario, Canada
| | - Carol Moralejo
- a Department of Chemical Engineering , University of Waterloo , Waterloo , Ontario, Canada
| | - William A Anderson
- a Department of Chemical Engineering , University of Waterloo , Waterloo , Ontario, Canada
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29
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Metcalf MJ, Stevens GJ, Robbins GA. Application of first order kinetics to characterize MTBE natural attenuation in groundwater. J Contam Hydrol 2016; 187:47-54. [PMID: 26878650 DOI: 10.1016/j.jconhyd.2016.02.001] [Citation(s) in RCA: 5] [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: 09/26/2015] [Revised: 12/24/2015] [Accepted: 02/02/2016] [Indexed: 06/05/2023]
Abstract
Methyl tertiary butyl ether (MTBE) was a gasoline oxygenate that became widely used in reformulated gasoline as a means to reduce air pollution in the 1990s. Unfortunately, many of the underground storage tanks containing reformulated gasoline experienced subsurface releases which soon became a health concern given the increase in public and private water supplies containing MTBE. Many states responded to this by banning the use of MTBE as an additive, including Connecticut. Although MTBE dissipates by natural attenuation, it continues to be prevalent in groundwater long after the Connecticut ban in 2004. This study estimated the rate of the natural attenuation in groundwater following the Connecticut ban by evaluating the MTBE concentration two years prior to and two years after the MTBE ban at eighty-three monitoring wells from twenty-two retail gasoline stations where MTBE contamination was observed. Sites chosen for this study had not undergone active remediation ensuring no artificial influence to the natural attenuation processes that controls the migration and dissipation of MTBE. Results indicate that MTBE has dissipated in the natural environment, at more than 80% of the sites and at approximately 82% of the individual monitoring wells. In general, dissipation approximated first order kinetics. Dissipation half-lives, calculated using concentration data from the two year period after the ban, ranged from approximately three weeks to just over seven years with an average half-life of 7.3 months with little variability in estimates for different site characteristics. The accuracy of first order estimates to predict further MTBE dissipation were tested by comparing predicted concentrations with those observed after the two year post-ban period; the predicted concentrations closely match the observed concentrations which supports the use of first order kinetics for predictions of this nature.
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Affiliation(s)
- Meredith J Metcalf
- Environmental Earth Science Department, Eastern Connecticut State University, 83 Windham Street, Willimantic, CT 06226, United States.
| | - Graham J Stevens
- Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Storrs, CT 06269, United States.
| | - Gary A Robbins
- Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Storrs, CT 06269, United States.
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30
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Balseiro-Romero M, Kidd PS, Monterroso C. Leachability of volatile fuel compounds from contaminated soils and the effect of plant exudates: A comparison of column and batch leaching tests. J Hazard Mater 2016; 304:481-489. [PMID: 26619047 DOI: 10.1016/j.jhazmat.2015.11.017] [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: 06/25/2015] [Revised: 11/07/2015] [Accepted: 11/10/2015] [Indexed: 06/05/2023]
Abstract
Volatile fuel compounds such as fuel oxygenates (FO) (MTBE and ETBE) and BTEX (benzene, toluene, ethylbenzene and xylene) are some of the most soluble components of fuel. Characterizing the leaching potential of these compounds is essential for predicting their mobility through the soil profile and assessing the risk of groundwater contamination. Plant root exudates can play an important role in the modification of contaminant mobility in soil-plant systems, and such effects should also be considered in leaching studies. Artificially spiked samples of A and B horizons from an alumi-umbric Cambisol were leached in packed-columns and batch experiments using Milli-Q water and plant root exudates as leaching agents. The leaching potential and rate were strongly influenced by soil-contaminant interactions and by the presence of root exudates. Organic matter in A horizon preferably sorbed the most non-polar contaminants, lowering their leaching potential, and this effect was enhanced by the presence of root exudates. On the other hand, the inorganic components of the B horizon, showed a greater affinity for polar molecules, and the presence of root exudates enhanced the desorption of the contaminants. Column experiments resulted in a more realistic protocol than batch tests for predicting the leaching potential of volatile organic compounds in dissimilar soils.
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Affiliation(s)
- María Balseiro-Romero
- Department of Soil Science and Agricultural Chemistry, University of Santiago de Compostela, Campus Vida, 15782 Santiago de Compostela, Spain.
| | - Petra S Kidd
- Instituto de Investigacións Agrobiolóxicas de Galicia (IIAG), Consejo Superior de Investigaciones Científicas (CSIC), 15780 Santiago de Compostela, Spain
| | - Carmen Monterroso
- Department of Soil Science and Agricultural Chemistry, University of Santiago de Compostela, Campus Vida, 15782 Santiago de Compostela, Spain
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Barekati-Goudarzi M, Boldor D, Nde DB. In-situ transesterification of seeds of invasive Chinese tallow trees (Triadica sebifera L.) in a microwave batch system (GREEN(3)) using hexane as co-solvent: Biodiesel production and process optimization. Bioresour Technol 2016; 201:97-104. [PMID: 26638139 DOI: 10.1016/j.biortech.2015.11.028] [Citation(s) in RCA: 6] [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: 10/07/2015] [Revised: 11/11/2015] [Accepted: 11/12/2015] [Indexed: 06/05/2023]
Abstract
In-situ transesterification (simultaneous extraction and transesterification) of Chinese tallow tree seeds into methyl esters using a batch microwave system was investigated in this study. A high degree of oil extraction and efficient conversion of oil to biodiesel were found in the proposed range. The process was further optimized in terms of product yields and conversion rates using Doehlert optimization methodology. Based on the experimental results and statistical analysis, the optimal production yield conditions for this process were determined as: catalyst concentration of 1.74wt.%, solvent ratio about 3 (v/w), reaction time of 20min and temperature of 58.1°C. H(+)NMR was used to calculate reaction conversion. All methyl esters produced using this method met ASTM biodiesel quality specifications.
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Affiliation(s)
- Mohamad Barekati-Goudarzi
- Louisiana State University Agricultural Center, BAE Department, Baton Rouge, LA 70803, United States
| | - Dorin Boldor
- Louisiana State University Agricultural Center, BAE Department, Baton Rouge, LA 70803, United States.
| | - Divine B Nde
- Louisiana State University Agricultural Center, BAE Department, Baton Rouge, LA 70803, United States; University of Bamenda, Department of Food Science and Bio-resource Technology, College of Technology, P.O. Box 39, Bamenda, Cameroon
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Abstract
Remediation of a soil contaminated with methyl tertiary butyl ether (MTBE) was studied by using the electrokinetic technique. A series of experimental tests were carried out on contaminated soil in an electro-osmotic apparatus at different applied gradients of voltage and time. The tests were conducted with distilled water and ethylenediaminetetra acetic acid (EDTA) solution as electrolyte. During each test the values of pH at anode and cathode reservoirs and also the discharge from cathode were measured. At the end of each test a number of soil samples were extracted from the middle of the soil at different distances from the anode and the removal of contaminant was measured by a gas chromatography apparatus. The results indicate that with EDTA as electrolyte the highest efficiency for removal of MTBE is achieved with 2.0 V/cm gradient and in the duration of 14 days. In addition, EDTA causes the values of pH to increase and decrease in the cathode and anode reservoirs, respectively. It also decreases the effluent and electro-osmotic permeability in comparison with distilled water. Experimental data were analysed by ANOVA and t-test methods. These statistical analyses showed significant difference (at 5% level) between the reference and other tests.
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Affiliation(s)
- A R Estabragh
- a Faculty of Soil and Water Engineering , University of Tehran , Karaj , Iran
| | - A T Bordbar
- a Faculty of Soil and Water Engineering , University of Tehran , Karaj , Iran
| | - F Ghaziani
- b Faculty of Agricultural , University of Tehran , Karaj , Iran
| | - A A Javadi
- c Computational Geomechanics Group, College of Engineering, Mathematics and Physical Sciences , University of Exeter , Devon , UK
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Ray JA, Kushnir MM, Rockwood AL, Meikle AW. Direct Measurement of Free Estradiol in Human Serum and Plasma by Equilibrium Dialysis-Liquid Chromatography-Tandem Mass Spectrometry. Methods Mol Biol 2016; 1378:99-108. [PMID: 26602122 DOI: 10.1007/978-1-4939-3182-8_12] [Citation(s) in RCA: 6] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We describe a direct method of measurement of free estradiol using equilibrium dialysis followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Serum aliquots and internal standards are extracted by liquid-liquid extraction using methyl-tert-butyl ether (MTBE) followed by derivatization with dansyl chloride. An API 5500 mass spectrometer operated in positive electrospray mode is used for detection.
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Affiliation(s)
- Julie A Ray
- ARUP Institute for Clinical and Experimental Pathology, 500 Chipeta Way, Salt Lake City, UT, 84108, USA.
| | - Mark M Kushnir
- ARUP Institute for Clinical and Experimental Pathology, 500 Chipeta Way, Salt Lake City, UT, 84108, USA.
| | - Alan L Rockwood
- ARUP Institute for Clinical and Experimental Pathology, 500 Chipeta Way, Salt Lake City, UT, 84108, USA.
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT, USA.
| | - A Wayne Meikle
- ARUP Institute for Clinical and Experimental Pathology, 500 Chipeta Way, Salt Lake City, UT, 84108, USA
- Department of Pathology, University of Utah, Salt Lake City, UT, USA
- Department of Medicine, University of Utah, Salt Lake City, UT, USA
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Tabélé C, Curti C, Kabri Y, Primas N, Vanelle P. Cross-Coupling Synthesis of Methylallyl Alkenes: Scope Extension and Mechanistic Study. Molecules 2015; 20:22890-9. [PMID: 26703547 PMCID: PMC6331887 DOI: 10.3390/molecules201219886] [Citation(s) in RCA: 7] [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: 11/20/2015] [Revised: 12/09/2015] [Accepted: 12/14/2015] [Indexed: 11/16/2022] Open
Abstract
Cross-coupling reactions between 2-methyl-2-propen-1-ol and various boronic acids are used to obtain aromatic-(2-methylallyl) derivatives. However, deboronation or isomerization side reactions may occur for several boronic acids. We describe herein the synthesis of original alkenes with good yields under mild reaction conditions that decrease these side reactions. The scope of this environmentally benign reaction is thereby extended to a wide variety of boronic acids. A mechanistic study was conducted and suggested a plausible catalytic cycle mechanism, pointing to the importance of the Lewis acidity of the boronic acid used.
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Affiliation(s)
- Clémence Tabélé
- Aix-Marseille Université, CNRS, ICR, UMR 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin-CS30064, 13385 Marseille cedex 05, France.
| | - Christophe Curti
- Aix-Marseille Université, CNRS, ICR, UMR 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin-CS30064, 13385 Marseille cedex 05, France.
| | - Youssef Kabri
- Aix-Marseille Université, CNRS, ICR, UMR 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin-CS30064, 13385 Marseille cedex 05, France.
| | - Nicolas Primas
- Aix-Marseille Université, CNRS, ICR, UMR 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin-CS30064, 13385 Marseille cedex 05, France.
| | - Patrice Vanelle
- Aix-Marseille Université, CNRS, ICR, UMR 7273, Laboratoire de Pharmaco-Chimie Radicalaire, Faculté de Pharmacie, 27 Boulevard Jean Moulin-CS30064, 13385 Marseille cedex 05, France.
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Piscitelli D, Zingaretti D, Verginelli I, Gavasci R, Baciocchi R. The fate of MtBE during Fenton-like treatments through laboratory scale column tests. J Contam Hydrol 2015; 183:99-108. [PMID: 26544517 DOI: 10.1016/j.jconhyd.2015.10.007] [Citation(s) in RCA: 2] [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: 05/12/2015] [Revised: 10/12/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
In Situ Chemical Oxidation (ISCO) based on the Fenton's process is a proven technology for the treatment of groundwater contaminated by organic compounds. Nevertheless, the application of this treatment process to methyl tert-butyl ether (MtBE) is questioned, as there are concerns about its capacity to achieve complete mineralization. Many existing studies have focused on water contaminated by MtBE and are thus not representative of in situ treatments since they do not consider the presence of soil. In this work, the effectiveness of a Fenton-like process for MtBE treatment was proven in soil column tests performed at operating conditions (i.e., oxidant and contaminant concentration and flow rates) resembling those typically used for in situ applications. No MtBE by-products were detected in any of the tested conditions, thus suggesting that the tert-butyl group of MtBE was completely degraded. A mass balance based on the CO2 produced was used as evidence that most of the MtBE removed was actually mineralized. Finally, the obtained results show that preconditioning of soil with a chelating agent (EDTA) significantly enhanced MtBE oxidation.
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Affiliation(s)
- Daniela Piscitelli
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - Daniela Zingaretti
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - Iason Verginelli
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - Renato Gavasci
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy
| | - Renato Baciocchi
- Laboratory of Environmental Engineering, Department of Civil Engineering and Computer Science Engineering, University of Rome "Tor Vergata", Via del Politecnico 1, 00133 Rome, Italy.
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36
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Julien M, Nun P, Robins RJ, Remaud GS, Parinet J, Höhener P. Insights into Mechanistic Models for Evaporation of Organic Liquids in the Environment Obtained by Position-Specific Carbon Isotope Analysis. Environ Sci Technol 2015; 49:12782-8. [PMID: 26443423 DOI: 10.1021/acs.est.5b03280] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Position-specific isotope effects (PSIEs) have been measured by isotope ratio monitoring (13)C nuclear magnetic resonance spectrometry during the evaporation of 10 liquids of different polarities under 4 evaporation modes (passive evaporation, air-vented evaporation, low pressure evaporation, distillation). The observed effects are used to assess the validity of the Craig-Gordon isotope model for organic liquids. For seven liquids the overall isotope effect (IE) includes a vapor-liquid contribution that is strongly position-specific in polar compounds but less so in apolar compounds and a diffusive IE that is not position-specific, except in the alcohols, ethanol and propan-1-ol. The diffusive IE is diminished under forced evaporation. The position-specific isotope pattern created by liquid-vapor IEs is manifest in five liquids, which have an air-side limitation for volatilization. For the alcohols, undefined processes in the liquid phase create additional PSIEs. Three other liquids with limitations on the liquid side have a lower, highly position-specific, bulk diffusive IE. It is concluded that evaporation of organic pollutants creates unique position-specific isotope patterns that may be used to assess the progress of remediation or natural attenuation of pollution and that the Craig-Gordon isotope model is valid for the volatilization of nonpolar organic liquids with air-side limitation of the volatilization rate.
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Affiliation(s)
- Maxime Julien
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230 , 2 rue de la Houssinière BP 92208, F-44322 Nantes, France
| | - Pierrick Nun
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230 , 2 rue de la Houssinière BP 92208, F-44322 Nantes, France
| | - Richard J Robins
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230 , 2 rue de la Houssinière BP 92208, F-44322 Nantes, France
| | - Gérald S Remaud
- EBSI Team, CEISAM, University of Nantes-CNRS UMR 6230 , 2 rue de la Houssinière BP 92208, F-44322 Nantes, France
| | - Julien Parinet
- Laboratoire Chimie Environnement, University of Aix-Marseille-CNRS FRE 3416 , place Victor Hugo 3, F-13331 Marseille, France
| | - Patrick Höhener
- Laboratoire Chimie Environnement, University of Aix-Marseille-CNRS FRE 3416 , place Victor Hugo 3, F-13331 Marseille, France
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Farobie O, Matsumura Y. Energy analysis for the production of biodiesel in a spiral reactor using supercritical tert-butyl methyl ether (MTBE). Bioresour Technol 2015; 196:65-71. [PMID: 26231125 DOI: 10.1016/j.biortech.2015.07.049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 06/04/2015] [Revised: 07/14/2015] [Accepted: 07/16/2015] [Indexed: 06/04/2023]
Abstract
In this study, energy analysis was conducted for the production of biodiesel in a spiral reactor using supercritical tert-butyl methyl ether (MTBE). This study aims to determine the net energy ratio (NER) and energy efficiency for the production of biodiesel using supercritical MTBE and to verify the effectiveness of the spiral reactor in terms of heat recovery efficiency. The analysis results revealed that the NER for this process was 0.92. Meanwhile, the energy efficiency was 0.98, indicating that the production of biodiesel in a spiral reactor using supercritical MTBE is an energy-efficient process. By comparing the energy supply required for biodiesel production between spiral and conventional reactors, the spiral reactor was more efficient than the conventional reactor.
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Affiliation(s)
- Obie Farobie
- Division of Energy and Environmental Engineering, Institute of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan
| | - Yukihiko Matsumura
- Division of Energy and Environmental Engineering, Institute of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan.
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38
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Wei M, Rakoczy J, Vogt C, Harnisch F, Schumann R, Richnow HH. Enhancement and monitoring of pollutant removal in a constructed wetland by microbial electrochemical technology. Bioresour Technol 2015; 196:490-499. [PMID: 26282780 DOI: 10.1016/j.biortech.2015.07.111] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [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: 05/30/2015] [Revised: 07/27/2015] [Accepted: 07/29/2015] [Indexed: 06/04/2023]
Abstract
A bench-scale constructed wetland combined with microbial electrochemical technology (MET-CW) was run for 400days with groundwater contaminated with benzene, methyl-tert-butyl ether (MTBE), and ammonium (NH4(+)). Four vertically stacked anode modules were embedded into a sand bed and connected with a stainless steel cathode placed in an open water pond. In the zone of presence of anode modules, significantly more benzene and MTBE were removed in the MET-CW compared to the control CW without MET in the first 150 operation days. Benzene was identified as primary electron donor at the anode. Benzene removal and current densities were linearly correlated, implying the potential of the system for electrochemically monitoring benzene biodegradation. Compound-specific isotope analysis (CSIA) indicated that benzene was initially activated by monohydroxylation forming intermediates which were subsequently oxidized accompanied by extracellular electron transfer, leading to current production. NH4(+) removal was not stimulated by MET.
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Affiliation(s)
- Manman Wei
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany; Faculty of Natural Sciences, Hohenheim University, 70593 Stuttgart, Germany
| | - Jana Rakoczy
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
| | - Carsten Vogt
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany.
| | - Falk Harnisch
- Department of Environmental Microbiology, Helmholtz Centre for Environmental Research-UFZ, Permoserstraße 15, 04318 Leipzig, Germany
| | - Reinhard Schumann
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
| | - Hans H Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ, Permoserstraβe 15, 04318 Leipzig, Germany
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Abedini Najafabadi H, Vossoughi M, Pazuki G. The role of co-solvents in improving the direct transesterification of wet microalgal biomass under supercritical condition. Bioresour Technol 2015; 193:90-96. [PMID: 26117240 DOI: 10.1016/j.biortech.2015.06.045] [Citation(s) in RCA: 5] [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: 04/10/2015] [Revised: 06/09/2015] [Accepted: 06/10/2015] [Indexed: 06/04/2023]
Abstract
In this research, direct conversion of wet algal biomass into biodiesel using supercritical methanol was studied. In this process, microalgal lipids simultaneously was extracted and converted to biodiesel under high pressure and temperature conditions without using any catalyst. Several experiments have been performed to optimize the methanol amount and it has been revealed that the best performance was achieved by using methanol/wet biomass ratio of 8:1. The effect of using various co-solvents in increasing the efficiency of the supercritical process was investigated. It has been shown that hexane was the most effective co-solvent and its optimal ratio respect to wet biomass was 6:1. The results indicated that compare to conventional extraction plus transesterification reaction, fatty acid methyl esters (FAMEs) yield was slightly higher in the direct conversion process. Moreover, increasing the moisture content up to 80% has no significant effect on reducing the performance of this process.
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Affiliation(s)
| | - Manouchehr Vossoughi
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran; Institute for Biotechnology and Environment (IBE), Sharif University of Technology, Tehran, Iran.
| | - Gholamreza Pazuki
- Department of Chemical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
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40
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Mihaich E, Erler S, Le Blanc G, Gallagher S. Short-term fish reproduction assays with methyl tertiary butyl ether with zebrafish and fathead minnow: Implications for evaluation of potential for endocrine activity. Environ Toxicol Chem 2015; 34:2013-2022. [PMID: 25866897 DOI: 10.1002/etc.3017] [Citation(s) in RCA: 2] [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: 11/20/2014] [Revised: 12/19/2014] [Accepted: 04/09/2015] [Indexed: 06/04/2023]
Abstract
The authors report on short-term fish reproduction assays in zebrafish and fathead minnow conducted to examine the potential for methyl tertiary butyl ether (MTBE) to cause effects on the endocrine system. Both studies were performed under good laboratory practice and in accordance with Organisation for Economic Co-operation and Development and US Environmental Protection Agency test guidelines. The results of the first study demonstrated that exposure to a high test concentration (147 mg/L) of MTBE impaired reproductive output of female zebrafish, evident by a reduction in fecundity. Based on the endpoints evaluated in the present study however, there was no supporting evidence to indicate that this effect was caused by disruption of or interaction with the endocrine system. In the second study, fathead minnows exposed to a wider but lower range of test concentrations showed no effects on any reproductive parameter of male or female fish, at the maximum recommended testing concentration of 100 mg/L (62 mg/L measured). The results of these 2 guideline studies indicate that MTBE does not interact with the hypothalamic-pituitary-gonadal axis of zebrafish or fathead minnow.
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Affiliation(s)
- Ellen Mihaich
- Environmental and Regulatory Resources, Durham, North Carolina, USA
| | - Steffen Erler
- SABIC, Saudi Basic Industries Corporation, Pittsfield, Massachusettes, USA
| | - Gerald Le Blanc
- Department of Biological Sciences, North Carolina State University, Raleigh, North Carolina, USA
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Farobie O, Matsumura Y. A comparative study of biodiesel production using methanol, ethanol, and tert-butyl methyl ether (MTBE) under supercritical conditions. Bioresour Technol 2015; 191:306-311. [PMID: 26004381 DOI: 10.1016/j.biortech.2015.04.102] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [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: 03/12/2015] [Revised: 04/26/2015] [Accepted: 04/27/2015] [Indexed: 06/04/2023]
Abstract
In this study, biodiesel production under supercritical conditions among methanol, ethanol, and tert-butyl methyl ether (MTBE) was compared in order to elucidate the differences in their reaction behavior. A continuous reactor was employed, and experiments were conducted at various reaction temperatures (270-400 °C) and reaction times (3-30 min) and at a fixed pressure of 20 MPa and an oil-to-reactant molar ratio of 1:40. The results showed that under the same reaction conditions, the supercritical methanol method provided the highest yield of biodiesel. At 350 °C and 20 MPa, canola oil was completely converted to biodiesel after 10, 30, and 30 min in the case of - supercritical methanol, ethanol, and MTBE, respectively. The reaction kinetics of biodiesel production was also compared for supercritical methanol, ethanol, and MTBE.
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Affiliation(s)
- Obie Farobie
- Department of Mechanical Science and Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan
| | - Yukihiko Matsumura
- Division of Energy and Environmental Engineering, Institute of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527, Japan.
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42
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Lin RYY, Wu FL, Li CT, Chen PY, Ho KC, Lin JT. High-performance aqueous/organic dye-sensitized solar cells based on sensitizers containing triethylene oxide methyl ether. ChemSusChem 2015; 8:2503-2513. [PMID: 26098636 DOI: 10.1002/cssc.201500589] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [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: 04/30/2015] [Revised: 05/19/2015] [Indexed: 06/04/2023]
Abstract
Metal-free dyes (EO1 to EO4) containing the hydrophilic triethylene oxide methyl ether (TEOME) unit in the spacer have been synthesized and used in dye-sensitized solar cells (DSSCs). Efficient lithium-ion trapping by TEOME results in improved open-circuit voltage (VOC ), leading to excellent conversion efficiency of the cells, ranging from 9.02 to 9.98 % with I(-) /I3 (-) electrolyte in acetonitrile under AM 1.5 illumination. The TEOME unit also enhances the wettability of the dye molecules for application in aqueous-based DSSCs. Aqueous-based DSSCs with a dual TEMPO/iodide electrolyte exhibit high VOC values (0.80-0.88 V) and very promising cell performances of up to 5.97 %.
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Affiliation(s)
- Ryan Yeh-Yung Lin
- Institute of Chemistry, Academia Sinica, Nankang 11529, Taipei (Taiwan)ca.edu.tw
| | - Feng-Ling Wu
- Institute of Chemistry, Academia Sinica, Nankang 11529, Taipei (Taiwan)ca.edu.tw
| | - Chun-Ting Li
- Department of Chemical Engineering, National Taiwan University, Taipei 10617 (Taiwan)
| | - Pei-Yu Chen
- Department of Chemical Engineering, National Taiwan University, Taipei 10617 (Taiwan)
| | - Kuo-Chuan Ho
- Department of Chemical Engineering, National Taiwan University, Taipei 10617 (Taiwan).
- Institute of Polymer Science and Engineering, National Taiwan University, Taipei 10617 (Taiwan).
| | - Jiann T Lin
- Institute of Chemistry, Academia Sinica, Nankang 11529, Taipei (Taiwan)ca.edu.tw.
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43
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Abstract
We present a method which uses DFT (quantum, QM) calculations to improve free energies of binding computed with classical force fields (classical, MM). To overcome the incomplete overlap of configurational spaces between MM and QM, we use a hybrid Monte Carlo approach to generate quickly correct ensembles of structures of intermediate states between a MM and a QM/MM description, hence taking into account a great fraction of the electronic polarization of the quantum system, while being able to use thermodynamic integration to compute the free energy of transition between the MM and QM/MM. Then, we perform a final transition from QM/MM to full QM using a one-step free energy perturbation approach. By using QM/MM as a stepping stone toward the full QM description, we find very small convergence errors (<1 kJ/mol) in the transition to full QM. We apply this method to compute hydration free energies, and we obtain consistent improvements over the MM values for all molecules we used in this study. This approach requires large-scale DFT calculations as the full QM systems involved the ligands and all waters in their simulation cells, so the linear-scaling DFT code ONETEP was used for these calculations.
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Affiliation(s)
- Chris Sampson
- †School of Chemistry, University of Southampton, University Road, Southampton, Hampshire, SO17 1BJ, United Kingdom
| | | | | | - Christopher Woods
- §School of Chemistry, University of Bristol, Cantocks Close, Bristol, Somerset, BS8 1TS, United Kingdom
| | - Chris-Kriton Skylaris
- †School of Chemistry, University of Southampton, University Road, Southampton, Hampshire, SO17 1BJ, United Kingdom
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44
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Bayse CA, Shoaf AL. Effect of Methoxy Substituents on the Activation Barriers of the Glutathione Peroxidase-Like Mechanism of an Aromatic Cyclic Seleninate. Molecules 2015; 20:10244-52. [PMID: 26046321 PMCID: PMC6272359 DOI: 10.3390/molecules200610244] [Citation(s) in RCA: 7] [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: 05/12/2015] [Revised: 05/26/2015] [Accepted: 06/01/2015] [Indexed: 01/09/2023] Open
Abstract
Density functional theory (DFT) models including explicit water molecules have been used to model the redox scavenging mechanism of aromatic cyclic seleninates. Experimental studies have shown that methoxy substitutions affect the rate of scavenging of reactive oxygen species differently depending upon the position. Activities are enhanced in the para position, unaffected in the meta, and decreased in the ortho. DFT calculations show that the activation barrier for the oxidation of the selenenyl sulfide, a proposed key intermediate, is higher for the ortho methoxy derivative than for other positions, consistent with the low experimental conversion rate.
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Affiliation(s)
- Craig A Bayse
- Department of Chemistry and Biochemistry, Old Dominion University, Hampton Boulevard, Norfolk, VA 23529, USA.
| | - Ashley L Shoaf
- Department of Chemistry and Biochemistry, Old Dominion University, Hampton Boulevard, Norfolk, VA 23529, USA.
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45
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Zhang W, Dong ZX, Gu T, Li NG, Zhang PX, Wu WY, Yu SP, Tang YP, Yang JP, Shi ZH. A new and efficient synthesis of 6-O-methylscutellarein, the major metabolite of the natural medicine scutellarin. Molecules 2015; 20:10184-91. [PMID: 26042857 PMCID: PMC6272442 DOI: 10.3390/molecules200610184] [Citation(s) in RCA: 5] [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: 04/23/2015] [Revised: 05/28/2015] [Accepted: 05/29/2015] [Indexed: 11/16/2022] Open
Abstract
In this paper, a new and efficient synthesis of 6-O-methylscutellarein (3), the major metabolite of the natural medicine scutellarin, is reported. Two hydroxyl groups at C-4′ and C-7 in 2 were selectively protected by chloromethyl methyl ether after the reaction conditions were optimized, then 6-O-methyl-scutellarein (3) was produced in high yield after methylation of the hydroxyl group at C-6 and subsequent deprotection of the two methyl ether groups.
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Affiliation(s)
- Wei Zhang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Ze-Xi Dong
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Ting Gu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Nian-Guang Li
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Peng-Xuan Zhang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Wen-Yu Wu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Shao-Peng Yu
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Yu-Ping Tang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Jian-Ping Yang
- National and Local Collaborative Engineering Center of Chinese Medicinal Resources, Industrialization and Formulae Innovative Medicine, Nanjing University of Chinese Medicine, Nanjing 210023, China.
| | - Zhi-Hao Shi
- Department of Organic Chemistry, China Pharmaceutical University, Nanjing 211198, China.
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Wang LH, Zhang ZD, Hong CY, He XH, You W, You YZ. Anion-dipole interactions make the homopolymers self-assemble into multiple nanostructures. Adv Mater 2015; 27:3202-3207. [PMID: 25873566 DOI: 10.1002/adma.201405579] [Citation(s) in RCA: 20] [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: 12/05/2014] [Revised: 02/23/2015] [Indexed: 06/04/2023]
Abstract
Anion-dipole interactions can make homopolymers self-assemble like an amphiphilic block copolymer. Generally, common homopolymers cannot self-assemble into multiple nanostructures. Here, it is reported that anion-dipole interactions can enable a number of homopolymers to achieve a variety of self-assembly behaviors in aqueous solution. Such interactions and self-assembly features have been exclusively reserved for amphiphilic (block) polymers until now.
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Affiliation(s)
- Long-Hai Wang
- Key Laboratory of Soft Matter Chemistry, Chinese Academy of Sciences, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Zi-Dan Zhang
- Department of Chemistry, Tianjin University, Tianjin, 300072, China
| | - Chun-Yan Hong
- Key Laboratory of Soft Matter Chemistry, Chinese Academy of Sciences, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
| | - Xue-Hao He
- Department of Chemistry, Tianjin University, Tianjin, 300072, China
| | - Wei You
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599-3290, USA
| | - Ye-Zi You
- Key Laboratory of Soft Matter Chemistry, Chinese Academy of Sciences, Department of Polymer Science and Engineering, University of Science and Technology of China, Hefei, 230026, Anhui, China
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47
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Ding CS, Meng Z, Xu YY, Miao J. [Formation Mechanism of the Disinfection By-product 1, 1-Dichloroacetone in Drinking Water]. Huan Jing Ke Xue 2015; 36:1662-1667. [PMID: 26314113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
A novel method using methyl tertiary butyl ether (MTBE) as extractant and 1,2-dibromopropane as internal standard for the determination of the disinfection by-producs 1,1-dichloroacetone (DCAce) by gas chromatography mass spectrometry (GC-MS) was described. The formation process of DCAce and its influencing factors were discussed with L-leucine as the precursor during the chloramination process. The results indicated that the DCAce production increased with the increase of chloramine dosage when the chloramine addition was in the range of 5-30 mg · L(-1). The DCAce amount produced under alkaline condition was higher than those produced under the neutral and acidic conditions, and the DCAce amount reduced with the increase of pH value. Temperature was another important factor that affected the DCAce formation from methylamine especially in the range of 15-35°C , and the higher the temperature, the more the DCAce produced. The formation process of DCAce from L-leucine by chloramine consisted of a series of complicated reactions, including substitution, oxidation, bond breaking, amino diazotization, reduction and so on, and eventually DCAce was formed.
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48
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Sheng H, Tang W, Yerabolu R, Kong JY, Williams PE, Zhang M, Kenttämaa HI. Mass spectrometric identification of the N-monosubstituted N-hydroxylamino functionality in protonated analytes via ion/molecule reactions in tandem mass spectrometry. Rapid Commun Mass Spectrom 2015; 29:730-734. [PMID: 26406487 DOI: 10.1002/rcm.7154] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Revised: 01/24/2015] [Accepted: 01/24/2015] [Indexed: 06/05/2023]
Abstract
RATIONALE N-Monosubstituted hydroxylamines correspond to an important class of metabolites for many bioactive molecules. In this study, a tandem mass spectrometric method based on ion/molecule reactions was developed for the identification of compounds with the N-monosubstituted hydroxylamino functionality. METHODS The diagnostic ion/molecule reaction occurs between protonated analytes with 2-methoxypropene (MOP) inside a linear quadrupole ion trap mass spectrometer. RESULTS Most protonated compounds with N-monosubstituted and disubstituted hydroxylamino and oxime functional groups react with MOP via proton transfer and formation of a stable adduct in a linear quadrupole ion trap mass spectrometer. However, only protonated compounds with N-monosubstituted hydroxylamino groups form the characteristic MOP adduct-MeOH product. Possible mechanisms of this reaction are discussed. CONCLUSIONS A method based on functional group-selective ion/molecule reactions in a linear quadrupole ion trap mass spectrometer has been demonstrated to allow the identification of protonated compounds with the N-monosubstituted hydroxylamino functionality. Only N-monosubstituted hydroxylamines react with MOP via formation of an adduct that has eliminated methanol.
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Affiliation(s)
- Huaming Sheng
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | - Weijuan Tang
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | - Ravikiran Yerabolu
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | - John Y Kong
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | - Peggy E Williams
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
| | | | - Hilkka I Kenttämaa
- Purdue University, Department of Chemistry, West Lafayette, IN, 47907, USA
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Zhang N, Schindelka J, Herrmann H, George C, Rosell M, Herrero-Martín S, Klán P, Richnow HH. Investigation of humic substance photosensitized reactions via carbon and hydrogen isotope fractionation. Environ Sci Technol 2015; 49:233-42. [PMID: 25427194 DOI: 10.1021/es502791f] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Humic substances (HS) acting as photosensitizers can generate a variety of reactive species, such as OH radicals and excited triplet states ((3)HS*), promoting the degradation of organic compounds. Here, we apply compound-specific stable isotope analysis (CSIA) to characterize photosensitized mechanisms employing fuel oxygenates, such as methyl tert-butyl ether (MTBE) and ethyl tert-butyl ether (ETBE), as probes. In oxygenated aqueous media, Λ (Δδ(2)H/Δδ(13)C) values of 23 ± 3 and 21 ± 3 for ETBE obtained by photosensitization by Pahokee Peat Humic Acid (PPHA) and Suwannee River Fulvic Acid (SRFA), respectively, were in the range typical for H-abstraction by OH radicals generated by photolysis of H2O2 (Λ = 24 ± 2). However, (3)HS* may become a predominant reactive species upon the quenching of OH radicals (Λ = 14 ± 1), and this process can also play a key role in the degradation of ETBE by PPHA photosensitization in deoxygenated media (Λ = 11 ± 1). This is in agreement with a model photosensitization by rose bengal (RB(2-)) in deoxygenated aqueous solutions resulting in one-electron oxidation of ETBE (Λ = 14 ± 1). Our results demonstrate that the use of CSIA could open new avenues for the assessment of photosensitization pathways.
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Affiliation(s)
- Ning Zhang
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research-UFZ , Permoserstrasse 15, 04318 Leipzig, Germany
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Cavanagh BA, Johnson PC, Daniels EJ. Reduction of diffusive contaminant emissions from a dissolved source in a lower permeability layer by sodium persulfate treatment. Environ Sci Technol 2014; 48:14582-14589. [PMID: 25386986 DOI: 10.1021/es5040443] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Residual contamination contained in lower permeability zones is difficult to remediate and can, through diffusive emissions to adjacent higher permeability zones, result in long-term impacts to groundwater. This work investigated the effectiveness of oxidant delivery for reducing diffusive emissions from lower permeability zones. The experiment was conducted in a 1.2 m tall × 1.2 m wide × 6 cm thick tank containing two soil layers having 3 orders of magnitude contrast in hydraulic conductivity. The lower permeability layer initially contained dissolved methyl tert-butyl ether (MTBE) and benzene, toluene, ethylbenzene, and p-xylenes (BTEX). The treatment involved delivery of 10% w/w nonactivated sodium persulfate (Na2S2O8) solution to the high permeability layer for 14 days. The subsequent diffusion into the lower permeability layer and contaminant emission response were monitored for about 240 days. The S2O8(2-) diffused about 14 cm at 1% w/w into the lower permeability layer during the 14 day delivery and continued diffusing deeper into the layer as well as back toward the higher-lower permeability interface after delivery ceased. Over 209 days, the S2O8(2-) diffused 60 cm into the lower permeability layer, the BTEX mass and emission rate were reduced by 95-99%, and the MTBE emission rate was reduced by 63%. The overall treatment efficiency was about 60-110 g-S2O8(2-)delivered/g-hydrocarbon oxidized, with a significant fraction of the oxidant delivered likely lost by back-diffusion and not involved in hydrocarbon destruction.
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Affiliation(s)
- Bridget A Cavanagh
- School of Sustainable Engineering and the Built Environment, Ira A Fulton Schools of Engineering, Arizona State University , Tempe, Arizona 85287, United States
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