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He C, Gao Q, Ye C, Yang G, Zhang P, Yang R, Zhang Q, Ma K. Development of a Purity Certified Reference Material for Vinyl Acetate. Molecules 2023; 28:6245. [PMID: 37687073 PMCID: PMC10488496 DOI: 10.3390/molecules28176245] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 08/21/2023] [Accepted: 08/22/2023] [Indexed: 09/10/2023] Open
Abstract
Vinyl acetate is a restricted substance in food products. The quantification of the organic impurities in vinyl acetate is a major problem due to its activity, instability, and volatility. In this paper, while using the mass balance method to determine the purity of vinyl acetate, an improved method was established for the determination of the content of three impurities in vinyl acetate reference material, and the GC-FID peak area normalization for vinyl acetate was calibrated. The three trace organic impurities were identified by gas chromatography tandem high-resolution mass spectrometry to be methyl acetate, ethyl acetate, and vinyl propionate. The content and relative correction factors for the three organic impurities were measured. The purity of vinyl acetate determined by the mass balance method was 99.90% with an expanded uncertainty of 0.30%, and the total content of organic impurities was 0.08% with a relative correction factor of 1.23%. The vinyl acetate reference material has been approved as a national certified reference material in China as GBW (E) 062710.
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Affiliation(s)
- Chen He
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Qin Gao
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Changwen Ye
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Guotao Yang
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Pengfei Zhang
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Rongchao Yang
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Qing Zhang
- Zhengzhou Tobacco Research Institute of China National Tobacco Corporation, Zhengzhou 450001, China; (C.H.); (Q.G.); (C.Y.); (G.Y.); (P.Z.); (R.Y.)
| | - Kang Ma
- Division of Chemical Metrology and Analytical Science, National Institute of Metrology, Beijing 100013, China
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Zhang X, Kang L, Zhu M. Density Functional Theory Study of Low-Dimensional (2D, 1D, 0D) Boron Nitride Nanomaterials Catalyzing Acetylene Acetate Reaction. Int J Mol Sci 2022; 23:9997. [PMID: 36077397 DOI: 10.3390/ijms23179997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 08/26/2022] [Accepted: 08/29/2022] [Indexed: 11/16/2022] Open
Abstract
In this paper, density functional theory (DFT) was used to study the possibility of low-dimensional (2D, 1D, 0D) boron nitride nanomaterials to catalyze acetylene acetate reaction, and further explore the possible source of this catalytic activity. It is found that the catalytic activity of boron nitride nanomaterials for acetylene acetate reaction will change with the change of the geometric structure (dimension) and reaction site of the catalyst. From the geometric structure, the reaction components and the zero-dimensional BN catalyst can form chemical bonds and form complexes, while only physical adsorption occurs on the surface of the one-dimensional and two-dimensional BN catalysts. From the reaction site, the properties of different C sites on the B12N12NC-C2H2 complexes are different. Namely, a C atom connected with a B atom is more likely to have an electrophilic reaction with H+, and a C atom connected with an N atom is more likely to have a nucleophilic reaction with CH3COO−. Through the study of three kinds of BN nanomaterials with low dimensions, we found that the zero-dimensional B12N12 nanocage broke the inherent reaction inertia of BN materials and showed good catalytic activity in an acetylene acetate reaction, which is very likely to be a non-metallic catalyst for the acetylene gas-phase preparation of vinyl acetate.
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Faraji M, Asnaashariisfahani M, Baharvand H, Fard HK. Decorated magnetic nanoparticles with polyvinyl alcohol brushes modified with metal chelate affinity groups for purification of proteins. Biotechnol Appl Biochem 2022; 70:560-567. [PMID: 35723527 DOI: 10.1002/bab.2378] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Accepted: 06/16/2022] [Indexed: 11/11/2022]
Abstract
Refining is a serious challenge in the production of recombinant proteins, and this study proposes a new and easy strategy for the synthesis of magnetic affinity nanoparticles. First, the nanoparticles attached to polyvinyl alcohol brushes were synthesized, and then the hydroxyl groups of this polymer were converted to chelate groups. The nanoparticles were examined by (SEM) scanning electron microscopy, (TEM) transmission electron microscopy, (DLS) dynamic light scattering, (FT-IR) Fourier transform infrared, (XRD) X-ray powder diffraction, (VSM) vibrating sample magnetometry, and (TGA) thermal gravimetric analysis. The results confirm that uniform and spherical magnetic polymer nanoparticles with high magnetization and superparamagnetic properties were successfully synthesized. The S100A9 protein, a His-tagged recombinant protein, was expressed and purified using the synthesized nanoparticles. According to the (SDS-PAGE) sulfate-polyacrylamide gel electrophoresis results, there is a high degree of resolution in protein separation. The synthesized nanoparticles have a high protein binding capacity of about 208 mg of protein per gram of nanoparticles.
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Affiliation(s)
- Maedeh Faraji
- Department of Chemistry, Islamic Azad University, North Tehran Branch, Tehran, Iran
| | | | - Habibollah Baharvand
- Faculty of Polymer Science, Iran Polymer and Petrochemical Institute, P.O. Box: 112/14975, Tehran, Iran
| | - Hassan Kabiri Fard
- Department of Chemistry, Islamic Azad University, North Tehran Branch, Tehran, Iran
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Durán U, Monroy O, Gómez J, Ramírez F. Influence of oxygen on the vinyl acetate elimination pathway and microbial community structure of methanogenic sludge. Water Environ Res 2022; 94:e1666. [PMID: 34837253 DOI: 10.1002/wer.1666] [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: 08/05/2021] [Revised: 11/10/2021] [Accepted: 11/17/2021] [Indexed: 06/13/2023]
Abstract
Methanogenic-aerobic coupled processes were used to biological degradation of vinyl acetate (VA) to provide evidence of oxygen role for their complete elimination from different angles. First, physiological characterization of a continuous methanogenic-aerobic reactor fed by VA and glucose (G) showed that by adding G, the VA got 100% hydrolyzed to acetate, and then, by adding 1 mg·L-1 ·d-1 of dissolved oxygen (DO), this acetate got methanized by 40% and aerobically mineralized by 60%. Second, batch assays in the presence and absence of sodium azide suggest that VA at different concentrations was eliminated by both anaerobic and aerobic metabolic pathways, because without azide and in the presence of 1 mg DO·L-1 increased methane and carbon dioxide formation rates at 80% and 75%, respectively. Finally, microbial population dynamics analysis of the reactor by DGGE-sequencing highlighted that Brevibacillus agri (aerobic) and Methanosarcina barkeri (anaerobic) were identified as responsible for VA elimination by up to 98.6%. PRACTITIONER POINTS: Vinyl acetate is removed by simultaneous methanation and aerobic respiration. Methanosarcina barkeri and Brevibacillus agri removed up to 99% of vinyl acetate. DO and VA have a selective effect on the metabolism and population dynamics.
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Affiliation(s)
- Ulises Durán
- Environmental Engineering Department, Engineering Institute UNAM, Mexico City, Mexico
| | - Oscar Monroy
- Biotechnology Department, Universidad Autónoma Metropolitana, Mexico City, Mexico
| | - Jorge Gómez
- Biotechnology Department, Universidad Autónoma Metropolitana, Mexico City, Mexico
| | - Florina Ramírez
- Biotechnology Department, Universidad Autónoma Metropolitana, Mexico City, Mexico
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Wolpers A, Baffie F, Monteil V, D'Agosto F. Statistical and Block Copolymers of Ethylene and Vinyl Acetate via Reversible Addition-Fragmentation Chain Transfer Polymerization. Macromol Rapid Commun 2021; 42:e2100270. [PMID: 34145658 DOI: 10.1002/marc.202100270] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 06/01/2021] [Indexed: 11/10/2022]
Abstract
A dithiocarbamate chain transfer agent (CTA) based on Z-group substituted with a diphenyl amine (-NPh2 ) moiety is selected for the synthesis of statistical and diblock copolymers of ethylene and vinyl acetate via reversible addition-fragmentation chain transfer polymerization. Benefiting from the good chain growth control of polyethylene (PE), poly(vinyl acetate) (PVAc), and poly(ethylene-co-vinyl acetate) (EVA) achieved with this CTA, linear diblock copolymers of the type EVA-b-PE, EVA-b-EVA, and PVAc-b-EVA are successfully synthesized. A three-arm EVA star is additionally obtained starting from a trifunctional dithiocarbamate CTA.
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Affiliation(s)
- Arne Wolpers
- Univ Lyon, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), Université Claude Bernard Lyon 1, 43 Bd du 11 Novembre 1918, Villeurbanne, 69616, France
| | - Florian Baffie
- Univ Lyon, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), Université Claude Bernard Lyon 1, 43 Bd du 11 Novembre 1918, Villeurbanne, 69616, France
| | - Vincent Monteil
- Univ Lyon, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), Université Claude Bernard Lyon 1, 43 Bd du 11 Novembre 1918, Villeurbanne, 69616, France
| | - Franck D'Agosto
- Univ Lyon, CPE Lyon, CNRS, UMR 5128, Catalysis, Polymerization, Processes and Materials (CP2M), Université Claude Bernard Lyon 1, 43 Bd du 11 Novembre 1918, Villeurbanne, 69616, France
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Park SK, Choi M, Kim DW, Park BJ, Shin EJ, Park S, Yun S. Dielectric Elastomers UV-Cured from Poly(dimethylsiloxane) Solution in Vinyl Acetate. Polymers (Basel) 2020; 12:E2660. [PMID: 33187228 DOI: 10.3390/polym12112660] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/04/2020] [Accepted: 11/05/2020] [Indexed: 12/31/2022] Open
Abstract
Poly(dimethylsiloxane) (PDMS) has been extensively used as an electroactive polymer material because it exhibits not only excellent moldability but also mechanical properties sufficient enough for electroactive performance despite low dielectric permittivity. Its low dielectric property is due to its molecular non-polarity. Here, we introduce a polar group into a PDMS elastomer by using vinyl acetate (VAc) as a crosslinker to improve the dielectric permittivity. We synthesized a high-molecular weight PDMS copolymer containing vinyl groups, namely poly(dimethylsiloxane-co-methylvinylsiloxane) (VPDMS), and prepared several of the VPDMS solutions in VAc. We obtained transparent PDMS films by UV curing of the solution layers. Electromechanical actuation-related physical properties of one of the UV-cured films were almost equivalent to or superior to those of platinum-catalyzed hydrosilylation-cured PDMS films. In addition, saponification of the UV-cured film significantly improved the electrical and mechanical properties (ɛ′ ~ 44.1 pF/m at 10 kHz, E ~ 350 kPa, ɛ ~ 320%). The chemical introduction of VAc into PDMS main chains followed by saponification would offer an efficacious method of enhancing the electroactive properties of PDMS elastomers.
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Wolpers A, Baffie F, Verrieux L, Perrin L, Monteil V, D'Agosto F. Iodine-Transfer Polymerization (ITP) of Ethylene and Copolymerization with Vinyl Acetate. Angew Chem Int Ed Engl 2020; 59:19304-19310. [PMID: 32667118 DOI: 10.1002/anie.202008872] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 07/10/2020] [Indexed: 11/09/2022]
Abstract
Controlled radical polymerization of ethylene using different commercially available, cheap, and non-toxic iodo alkyls is performed by iodine transfer polymerization (ITP) under mild conditions (≤100 °C and ≤200 bar). The formed well-defined iodo end-capped polyethylene (PE-I) species is very stable upon storage. Narrow molar-mass distributions (dispersities around 1.6) were obtained up to number average molar masses of 7300 g mol-1 . The ethylene copolymerization by ITP (ITcoP) with vinyl acetate allowed to form a broad range of poly(ethylene-co-vinyl acetate) (EVA) containing from 0 to 85 mol % of VAc unit. In addition, EVA-b-PE block copolymers or EVA-b-EVA gradient block copolymers with different content of VAc in the blocks were obtained for the first time using ITP. Finally, reactivity trends were explored by a theoretical mechanistic study. This highly versatile synthetic platform provides a straightforward access to a diverse range of well-defined PE based polymer materials.
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Affiliation(s)
- A Wolpers
- Université de Lyon, Université Lyon 1, CPE Lyon, CNRS UMR 5265, Laboratoire C2P2, Équipe LCPP, 69616, Villeurbanne, CEDEX, France
| | - F Baffie
- Université de Lyon, Université Lyon 1, CPE Lyon, CNRS UMR 5265, Laboratoire C2P2, Équipe LCPP, 69616, Villeurbanne, CEDEX, France
| | - L Verrieux
- Université de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, INSA-Lyon, CNRS, UMR 5246, ICBMS, 43 Bd du 11 Novembre 1918, 69616, Villeurbanne, France
| | - L Perrin
- Université de Lyon, Université Claude Bernard Lyon 1, CPE Lyon, INSA-Lyon, CNRS, UMR 5246, ICBMS, 43 Bd du 11 Novembre 1918, 69616, Villeurbanne, France
| | - V Monteil
- Université de Lyon, Université Lyon 1, CPE Lyon, CNRS UMR 5265, Laboratoire C2P2, Équipe LCPP, 69616, Villeurbanne, CEDEX, France
| | - F D'Agosto
- Université de Lyon, Université Lyon 1, CPE Lyon, CNRS UMR 5265, Laboratoire C2P2, Équipe LCPP, 69616, Villeurbanne, CEDEX, France
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Zhang Y, Bei W, Qin Z. Preparation and Characterization of Soap-Free Vinyl Acetate/Butyl Acrylate Copolymer Latex. Materials (Basel) 2020; 13:E865. [PMID: 32075137 PMCID: PMC7078716 DOI: 10.3390/ma13040865] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 02/11/2020] [Accepted: 02/13/2020] [Indexed: 11/16/2022]
Abstract
The soap-free emulsion of vinyl acetate (VAc)/butyl acrylate (BA) copolymer was prepared by a semi-continuous and pre-emulsification polymerization method, using ammonium sulfate allyloxy nonylphenoxy poly(ethyleneoxy) (10) ether (DNS-86) as a reactive emulsifier. The effects of DNS-86 on the stability of the emulsion and the properties of the latex film were investigated. The infrared spectrum, thermal stability, glass transition temperature and micromorphology of latex were also studied. The results showed that the emulsion had the best stability and the conversion rate reached a maximum of 98.46% when the DNS-86 amount was 4 wt % of the total amount of monomers. Compared with the PVAc latex synthesized with octylphenol polyoxyethylene ether (10) (OP-10), the latex prepared with DNS-86 has higher thermal stability and ionic stability, whereas the latex film has better water resistance.
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Affiliation(s)
| | | | - Zhiyong Qin
- School of Resources, Environment and Materials, Guangxi university, Nanning 530000, China; (Y.Z.); (W.B.)
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9
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Hung KC, Yang CN, Yang TC, Wu TL, Chen YL, Wu JH. Characterization and Thermal Stability of Acetylated Slicewood Production by Alkali-Catalyzed Esterification. Materials (Basel) 2017; 10:ma10040393. [PMID: 28772751 PMCID: PMC5506890 DOI: 10.3390/ma10040393] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 03/28/2017] [Accepted: 04/04/2017] [Indexed: 11/16/2022]
Abstract
This study was compared and characterized two different alkali (potassium carbonate (PC) and potassium acetate (PA))-catalyzed acetylations of slicewood with vinyl acetate (VA) by a vapor phase reaction. The results revealed that the esterification reaction between VA and the hydroxyl groups of slicewood could be improved by using PC or PA as a catalyst. Additionally, a significant weight percent gain was obtained after VA acetylation with 5% of catalyst. Furthermore, the reactivity of the cellulose hydroxyl groups for VA acetylation was more pronounced at the C2 reactive site compared to acetylation with acetic anhydride. On the other hand, the apparent activation energy of thermal decomposition between 10% and 70% conversion is 174–183, 194–200, and 183–186 kJ/mol for unmodified slicewood and VA-acetylated slicewood with PC and PA, respectively. Accordingly, the thermal stability of the slicewood could be effectively enhanced by VA acetylation, especially for using the PC as a catalyst.
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Affiliation(s)
- Ke-Chang Hung
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
| | - Chen-Ning Yang
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
| | - Teng-Chun Yang
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
| | - Tung-Lin Wu
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
| | - Yong-Long Chen
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
| | - Jyh-Horng Wu
- Department of Forestry, National Chung Hsing University, Taichung 402, Taiwan.
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De Yan H, Li Q, Wang Z. Efficient kinetic resolution of (±)-menthol by a lipase from Thermomyces lanuginosus. Biotechnol Appl Biochem 2015; 64:87-91. [PMID: 26549685 DOI: 10.1002/bab.1457] [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] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Accepted: 11/03/2015] [Indexed: 12/30/2022]
Abstract
A lipase from Thermomyces lanuginosus (Lipozyme TL IM) exhibited high enantioselectivity for kinetic resolution of (±)-menthol in organic solvent. The various reaction parameters affecting the conversion and enantioselectivity were studied. The optimum reaction conditions for the transesterification reaction were found with vinyl acetate in the solvent of methyl tert-butyl ether with a vinyl acetate:(±)-menthol molar ratio of 5:1 and an enzyme concentration of 200 g/L at 30 °C. In these conditions, (-)-menthyl acetate with 99.3% enantiomeric excess was obtained, whereas the conversion was 34.7% with the reaction time of 12 H at the substrate concentration of 0.5 M. In addition, the enzyme allowed the substrate loading to be increased up to 1.5 M without the decrease of the enantioselectivity. These results indicated that Lipozyme TL IM was a promising biocatalyst in the resolution of (±)-menthol.
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Affiliation(s)
- Hong De Yan
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou, People's Republic of China
| | - Qin Li
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou, People's Republic of China
| | - Zhao Wang
- College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou, People's Republic of China
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Devendran S, Yadav GD. Lipase-catalyzed kinetic resolution of (±)-1-(2-furyl) ethanol in nonaqueous media. Chirality 2014; 26:286-92. [PMID: 24733779 DOI: 10.1002/chir.22317] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Accepted: 02/03/2014] [Indexed: 12/20/2022]
Abstract
S-1-(2-Furyl) ethanol serves as an important chiral building block for the preparation of various natural products, fine chemicals, and is widely used in the chemical and pharmaceutical industries. In this work, lipase-catalyzed kinetic resolution of (R/S)-1-(2-furyl) ethanol using different acyl donors was investigated. Vinyl esters are good acyl donors vis-à-vis alkyl esters for kinetic resolution. Among them, vinyl acetate was found to be the best acyl donor. Different immobilized lipases such as Rhizomucor miehei lipase, Thermomyces lanuginosus lipase, and Candida antarctica lipase B were evaluated for this reaction, among which C. antarctica lipase B, immobilized on acrylic resin (Novozym 435), was found to be the best catalyst in n-heptane as solvent. The effect of various parameters was studied in a systematic manner. Maximum conversion of 47% and enantiomeric excess of the substrate (ees ) of 89% were obtained in 2 h using 5 mg of enzyme loading with an equimolar ratio of alcohol to vinyl acetate at 60 °C at a speed of 300 rpm in a batch reactor. From the analysis of progress curve and initial rate data, it was concluded that the reaction followed the ordered bi-bi mechanism with dead-end ester inhibition. Kinetic parameters were obtained by using nonlinear regression. This process is more economical, green, and easily scalable than the chemical processes.
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Affiliation(s)
- Saravanan Devendran
- Department of Chemical Engineering, Institute of Chemical Technology, Nathalal Parekh Marg, Mumbai-400019, India
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Budinsky R, Gollapudi B, Albertini RJ, Valentine R, Stavanja M, Teeguarden J, Fensterheim R, Rick D, Lardie T, McFadden L, Green A, Recio L. Nonlinear responses for chromosome and gene level effects induced by vinyl acetate monomer and its metabolite, acetaldehyde in TK6 cells. Environ Mol Mutagen 2013; 54:755-768. [PMID: 24038327 DOI: 10.1002/em.21809] [Citation(s) in RCA: 6] [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: 03/08/2013] [Revised: 06/26/2013] [Accepted: 07/08/2013] [Indexed: 06/02/2023]
Abstract
Vinyl acetate monomer (VAM) produced rat nasal tumors at concentrations in the hundreds of parts per million. However, VAM is weakly genotoxic in vitro and shows no genotoxicity in vivo. A European Union Risk Assessment concluded that VAM's hydrolysis to acetaldehyde (AA), via carboxylesterase, is a critical key event in VAM's carcinogenic potential. In the following study, we observed increases in micronuclei (MN) and thymidine kinase (Tk) mutants that were dependent on the ability of TK6 cell culture conditions to rapidly hydrolyze VAM to AA. Heat-inactivated horse serum demonstrated a high capacity to hydrolyze VAM to AA; this activity was highly correlated with a concomitant increase in MN. In contrast, heat-inactivated fetal bovine serum (FBS) did not hydrolyze VAM and no increase in MN was observed. AA's ability to induce MN was not impacted by either serum since it directly forms Schiff bases with DNA and proteins. Increased mutant frequency at the Tk locus was similarly mitigated when AA formation was not sufficiently rapid, such as incubating VAM in the presence of FBS for 4 hr. Interestingly, neither VAM nor AA induced mutations at the HPRT locus. Finally, cytotoxicity paralleled genotoxicity demonstrating that a small degree of cytotoxicity occurred prior to increases in MN. These results established 0.25 mM as a consistent concentration where genotoxicity first occurred for both VAM and AA provided VAM is hydrolyzed to AA. This information further informs significant key events related to the mode of action of VAM-induced nasal mucosal tumors in rats.
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