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Jia HY, Zong MH, Yu HL, Li N. Dehydrogenase-Catalyzed Oxidation of Furanics: Exploitation of Hemoglobin Catalytic Promiscuity. CHEMSUSCHEM 2017; 10:3524-3528. [PMID: 28786206 DOI: 10.1002/cssc.201701288] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 08/06/2017] [Indexed: 06/07/2023]
Abstract
The catalytic promiscuity of hemoglobin (Hb) was explored for regenerating oxidized nicotinamide cofactors [NAD(P)+ ]. With H2 O2 as oxidant, Hb efficiently oxidized NAD(P)H into NAD(P)+ within 30 min. The new NAD(P)+ regeneration system was coupled with horse liver alcohol dehydrogenase (HLADH) for the oxidation of bio-based furanics such as furfural and 5-hydroxymethylfurfural (HMF). The target acids (e.g., 2,5-furandicarboxylic acid, FDCA) were prepared with moderate-to-good yields. The enzymatic regeneration method was applied in l-glutamic dehydrogenase (DH)-mediated oxidative deamination of lglutamate and for l-lactic-DH-mediated oxidation of l-lactate, which furnished α-ketoglutarate and pyruvate in yields of 97 % and 81 %, respectively. A total turnover number (TTON) of up to approximately 5000 for cofactor and an E factor of less than 110 were obtained in the bi-enzymatic cascade synthesis of α-ketoglutarate. Overall, a proof-of-concept based on catalytic promiscuity of Hb was provided for in situ regeneration of NAD(P)+ in DH-catalyzed oxidation reactions.
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Wei P, Cui YH, Zong MH, Xu P, Zhou J, Lou WY. Enzymatic characterization of a recombinant carbonyl reductase from Acetobacter sp. CCTCC M209061. BIORESOUR BIOPROCESS 2017; 4:39. [PMID: 28913159 PMCID: PMC5573764 DOI: 10.1186/s40643-017-0169-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/17/2017] [Indexed: 12/20/2022] Open
Abstract
Background Acetobacter sp. CCTCC M209061 could catalyze carbonyl compounds to chiral alcohols following anti-Prelog rule with excellent enantioselectivity. Therefore, the enzymatic characterization of carbonyl reductase (CR) from Acetobacter sp. CCTCC M209061 needs to be investigated. Results A CR from Acetobacter sp. CCTCC M209061 (AcCR) was cloned and expressed in E. coli. AcCR was purified and characterized, finding that AcCR as a dual coenzyme-dependent short-chain dehydrogenase/reductase (SDR) was more preferred to NADH for biocatalytic reactions. The AcCR was activated and stable when the temperature was under 35 °C and the pH range was from 6.0 to 8.0 for the reduction of 4′-chloroacetophenone with NADH as coenzyme, and the optimal temperature and pH were 45 °C and 8.5, respectively, for the oxidation reaction of isopropanol with NAD+. The enzyme showed moderate thermostability with half-lives of 25.75 h at 35 °C and 13.93 h at 45 °C, respectively. Moreover, the AcCR has broad substrate specificity to a range of ketones and ketoesters, and could catalyze to produce chiral alcohol with e.e. >99% for the majority of tested substrates following the anti-Prelog rule. Conclusions The recombinant AcCR exhibited excellent enantioselectivity, broad substrate spectrum, and highly stereoselective anti-Prelog reduction of prochiral ketones. These results suggest that AcCR is a powerful catalyst for the production of anti-Prelog alcohols.The biocatalytic reactions conducted with the recombinant AcCR ![]()
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Wen P, Feng K, Yang H, Huang X, Zong MH, Lou WY, Li N, Wu H. Electrospun core-shell structured nanofilm as a novel colon-specific delivery system for protein. Carbohydr Polym 2017; 169:157-166. [DOI: 10.1016/j.carbpol.2017.03.082] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 03/21/2017] [Accepted: 03/24/2017] [Indexed: 11/26/2022]
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Xu P, Zheng GW, Zong MH, Li N, Lou WY. Recent progress on deep eutectic solvents in biocatalysis. BIORESOUR BIOPROCESS 2017; 4:34. [PMID: 28794956 PMCID: PMC5522511 DOI: 10.1186/s40643-017-0165-5] [Citation(s) in RCA: 148] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 07/16/2017] [Indexed: 01/19/2023] Open
Abstract
Deep eutectic solvents (DESs) are eutectic mixtures of salts and hydrogen bond donors with melting points low enough to be used as solvents. DESs have proved to be a good alternative to traditional organic solvents and ionic liquids (ILs) in many biocatalytic processes. Apart from the benign characteristics similar to those of ILs (e.g., low volatility, low inflammability and low melting point), DESs have their unique merits of easy preparation and low cost owing to their renewable and available raw materials. To better apply such solvents in green and sustainable chemistry, this review firstly describes some basic properties, mainly the toxicity and biodegradability of DESs. Secondly, it presents several valuable applications of DES as solvent/co-solvent in biocatalytic reactions, such as lipase-catalyzed transesterification and ester hydrolysis reactions. The roles, serving as extractive reagent for an enzymatic product and pretreatment solvent of enzymatic biomass hydrolysis, are also discussed. Further understanding how DESs affect biocatalytic reaction will facilitate the design of novel solvents and contribute to the discovery of new reactions in these solvents.
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Wen P, Wen Y, Huang X, Zong MH, Wu H. Preparation and Characterization of Protein-Loaded Electrospun Fiber Mat and Its Release Kinetics. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:4786-4796. [PMID: 28535347 DOI: 10.1021/acs.jafc.7b01830] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
For the enhancement of protein's bioavailability, a specific delivery system was developed by coaxial electrospinning. Bovine serum albumin (BSA) was used as protein model, and the core-sheath fiber mat was fabricated using sodium alginate as shell layer and the BSA-loaded chitosan nanoparticle that was prepared previously as core layer. By optimizing electrospinning parameters, uniform fibers with diameters ranging from 200-600 nm were obtained, and transmission electron microscopy and confocal laser scanning microscopy revealed their core-sheath structures. Fourier transform infrared spectroscopy (FTIR) analysis demonstrated that there existed molecular interaction between components, which enhanced the mat's thermal stability and mechanic property. It was found that the predominant release mechanism of BSA from fiber mat was erosion, and little change occurred in the secondary structure of encapsulated BSA indicated by FTIR and circular dichroism analysis. The study shows that the obtained fiber mat is a potential delivery system for protein.
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Xia GH, Cao SL, Xu P, Li XH, Zhou J, Zong MH, Lou WY. Inside Cover: Preparation of a Nanobiocatalyst by Efficiently Immobilizing Aspergillus niger
Lipase onto Magnetic Metal-Biomolecule Frameworks (BioMOF) (ChemCatChem 10/2017). ChemCatChem 2017. [DOI: 10.1002/cctc.201700741] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Xia GH, Cao SL, Xu P, Li XH, Zhou J, Zong MH, Lou WY. Preparation of a Nanobiocatalyst by Efficiently Immobilizing Aspergillus niger
Lipase onto Magnetic Metal-Biomolecule Frameworks (BioMOF). ChemCatChem 2017. [DOI: 10.1002/cctc.201700070] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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An YX, Zong MH, Hu SQ, Li N. Effect of residual lignins present in cholinium ionic liquid-pretreated rice straw on the enzymatic hydrolysis of cellulose. Chem Eng Sci 2017. [DOI: 10.1016/j.ces.2016.12.014] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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84
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Cao SL, Deng X, Xu P, Huang ZX, Zhou J, Li XH, Zong MH, Lou WY. Highly Efficient Enzymatic Acylation of Dihydromyricetin by the Immobilized Lipase with Deep Eutectic Solvents as Cosolvent. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2017; 65:2084-2088. [PMID: 28244316 DOI: 10.1021/acs.jafc.7b00011] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
A novel deep eutectic solvent (DES)-DMSO cosolvent system has been, for the first time, successfully used as the reaction medium for the enzymatic acylation of dihydromyricetin (DMY) catalyzed by the immobilized lipase from Aspergillus niger (ANL). The cosolvent mixture, ChCl:Glycerol-DMSO (1:3, v/v) proved to be the optimal medium. With the newly developed cosolvent, the initial reaction rate of enzymatic acylation of DMY achieved 11.1 mM/h and the conversion of DMY was 91.6%. ANL@PD-MNPs is stable and recyclable in this cosolvent, offering 90% conversion rate after repeated use of 5 times. The lipid-solubility of DMY-16-acetate was 10 times higher than that of its raw materials DMY. The results showed that the DMY-16-acetate product exhibits good antioxidative activity. The present research illustrated that the use of DES-DMSO cosolvent may become a feasible alternative for the synthesis of DMY ester.
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Li YM, Zhang XY, Li N, Xu P, Lou WY, Zong MH. Biocatalytic Reduction of HMF to 2,5-Bis(hydroxymethyl)furan by HMF-Tolerant Whole Cells. CHEMSUSCHEM 2017; 10:372-378. [PMID: 27966286 DOI: 10.1002/cssc.201601426] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 10/22/2016] [Indexed: 06/06/2023]
Abstract
Catalytic upgrading of 5-hydroxymethylfurfural (HMF), an important biobased platform chemical for high-value products, is currently of great interest. In this work, a new highly HMFtolerant yeast strain-Meyerozyma guilliermondii SC1103 was isolated, and biocatalytic reduction of HMF to 2,5-bis(hydroxymethyl)furan (BHMF) using its resting cells was reported. Cosubstrates exerted a significant effect on the catalytic activity and selectivity of microbial cells as well as their HMF-tolerant levels whereas the nitrogen source and mineral salts had no effects. In addition, M. guilliermondii SC1103 cells exhibited good catalytic performances within the range of pH 4.0-10.0. The yeast was highly tolerant to both HMF (up to 110 mm) and BHMF (up to 200 mm). In addition, 100 mm HMF could be selectively reduced to BHMF within 12 h by its resting cells in the presence of 100 mm glucose (as cosubstrate), with a yield of 86 % and selectivity of >99 %. The production of 191 mm of BHMF was realized within 24.5 h by using a fed-batch strategy, with a productivity of approximately 24 g L-1 per day. In addition, this new biocatalytic approach was applied for the reduction of furfural and 5-methylfurfural, affording the corresponding furfuryl alcohols with yields of 83 and 89 %, respectively.
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Liu LP, Zong MH, Linhardt RJ, Lou WY, Li N, Huang C, Wu H. Mechanistic insights into the effect of imidazolium ionic liquid on lipid production by Geotrichum fermentans. BIOTECHNOLOGY FOR BIOFUELS 2016; 9:266. [PMID: 28018484 PMCID: PMC5162095 DOI: 10.1186/s13068-016-0682-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 12/06/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Ionic liquid (IL) pretreatment has emerged as a promising technique that enables complete utilization of lignocellulosic biomass for biofuel production. However, imidazolium IL has recently been shown to exhibit inhibitory effect on cell growth and product formation of industrial microbes, such as oleaginous microorganisms. To date, the mechanism of this inhibition remains largely unknown. RESULTS In this study, the feasibility of [Bmim][OAc]-pretreated rice straw hydrolysate as a substrate for microbial lipid production by Geotrichum fermentans, also known as Trichosporon fermentans, was evaluated. The residual [Bmim][OAc] present in the hydrolysate caused a reduction in biomass and lipid content (43.6 and 28.1%, respectively) of G. fermentans, compared with those of the control (7.8 g/L and 52.6%, respectively). Seven imidazolium ILs, [Emim][DEP], [Emim]Cl, [Amim]Cl, [Bmim]Cl, [Bzmim]Cl, [Emim][OAc], and [Bmim][OAc], capable of efficient pretreatment of lignocellulosic biomass were tested for their effects on the cell growth and lipid accumulation of G. fermentans to better understand the impact of imidazolium IL on the lipid production. All the ILs tested inhibited the cell growth and lipid accumulation. In addition, both the cation and the anion of IL contributed to IL toxicity. The side chain of IL cations showed a clear impact on toxicity. On examining IL anions, [OAc]- was found to be more toxic than those of [DEP]- and Cl-. IL exhibited its toxicity by inhibiting sugar consumption and key enzyme (malic enzyme and ATP-citrate lyase) activities of G. fermentans. Cell membrane permeability was also altered to different extents in the presence of various ILs. Scanning electron microscopy revealed that IL induces fibrous structure on the surface of G. fermentans cell, which might represent an adaptive mechanism of the yeast to IL. CONCLUSIONS This work gives some mechanistic insights into the impact of imidazolium IL on the cell growth and lipid accumulation of oleaginous yeast, which is important for IL integration in lignocellulosic biofuel production, especially for microbial lipid production.
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Zhang XL, Zong MH, Li N. Penicillin acylase-catalyzed synthesis of N-bromoacetyl-7-aminocephalosporanic acid, the key intermediate for the production of cefathiamidine. BIORESOUR BIOPROCESS 2016; 3:49. [PMID: 27917366 PMCID: PMC5116309 DOI: 10.1186/s40643-016-0127-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 11/15/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Enzymatic approaches have become promising alternatives to chemical methods for the production of semi-synthetic β-lactam antibiotics. In this work, enzymatic synthesis of N-bromoacetyl-7-aminocephalosporanic acid (N-bromoacetyl-7-ACA), the key intermediate for the production of cefathiamidine, was reported for the first time. RESULTS Of the immobilized penicillin acylases (PAs) tested, PGA-750 was the best biocatalyst. Optimization of the biocatalytic process was conducted. The optimal acyl donor, molar ratio of acyl donor to 7-ACA, pH, temperature, 7-ACA concentration, and enzyme dosage were methyl bromoacetate, 3, 7.5, 20 °C, 50 mmol/L and 4 U/mL, respectively. Under the optimal conditions, enzymatic N-acylation of 7-ACA with methyl bromoacetate afforded the desired product with the yield of 85% in 2 h, where the synthesis/hydrolysis (S/H) ratio was approximately 1.5. The immobilized enzyme PGA-750 exhibited good operational stability, and the relative yields of approximately 90% and 63% were achieved, respectively, when it was reused in 7th and 11th batch. CONCLUSIONS An enzymatic approach to N-bromoacetyl-7-ACA, the key intermediate for the industrial production of cefathiamidine, has been developed successfully in a fully aqueous medium. The present work may open up a novel opportunity for the production of cefathiamidine through a simple and green process.Graphical abstractEnzymatic synthesis of N-bromoacetyl-7-ACA, the key intermediate for the production of cefathiamidine, was reported for the first time.
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Hu YD, Zong MH, Li N. Enzymatic synthesis and anti-oxidative activities of plant oil-based ascorbyl esters in 2-methyltetrahydrofuran-containing mixtures. BIOCATAL BIOTRANSFOR 2016. [DOI: 10.1080/10242422.2016.1247820] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Wei P, Gao JX, Zheng GW, Wu H, Zong MH, Lou WY. Engineering of a novel carbonyl reductase with coenzyme regeneration in E. coli for efficient biosynthesis of enantiopure chiral alcohols. J Biotechnol 2016; 230:54-62. [DOI: 10.1016/j.jbiotec.2016.05.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 04/24/2016] [Accepted: 05/03/2016] [Indexed: 12/22/2022]
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Xu P, Du PX, Zong MH, Li N, Lou WY. Combination of deep eutectic solvent and ionic liquid to improve biocatalytic reduction of 2-octanone with Acetobacter pasteurianus GIM1.158 cell. Sci Rep 2016; 6:26158. [PMID: 27185089 PMCID: PMC4868980 DOI: 10.1038/srep26158] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 04/27/2016] [Indexed: 01/23/2023] Open
Abstract
The efficient anti-Prelog asymmetric reduction of 2-octanone with Acetobacter pasteurianus GIM1.158 cells was successfully performed in a biphasic system consisting of deep eutectic solvent (DES) and water-immiscible ionic liquid (IL). Various DESs exerted different effects on the synthesis of (R)-2-octanol. Choline chloride/ethylene glycol (ChCl/EG) exhibited good biocompatibility and could moderately increase the cell membrane permeability thus leading to the better results. Adding ChCl/EG increased the optimal substrate concentration from 40 mM to 60 mM and the product e.e. kept above 99.9%. To further improve the reaction efficiency, water-immiscible ILs were introduced to the reaction system and an enhanced substrate concentration (1.5 M) was observed with C4MIM·PF6. Additionally, the cells manifested good operational stability in the reaction system. Thus, the efficient biocatalytic process with ChCl/EG and C4MIM·PF6 was promising for efficient synthesis of (R)-2-octanol.
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Cao SL, Huang YM, Li XH, Xu P, Wu H, Li N, Lou WY, Zong MH. Preparation and Characterization of Immobilized Lipase from Pseudomonas Cepacia onto Magnetic Cellulose Nanocrystals. Sci Rep 2016; 6:20420. [PMID: 26843037 PMCID: PMC4740797 DOI: 10.1038/srep20420] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 01/04/2016] [Indexed: 11/12/2022] Open
Abstract
Magnetic cellulose nanocrystals (MCNCs) were prepared and used as an enzyme support for immobilization of Pseudomonas cepacialipase (PCL). PCL was successfully immobilized onto MCNCs (PCL@MCNC) by a precipitation-cross-linking method. The resulting PCL@MCNC with a nanoscale size had high enzyme loading (82.2 mg enzyme/g) and activity recovery (95.9%). Compared with free PCL, PCL@MCNC exhibited significantly enhanced stability and solvent tolerance, due to the increase of enzyme structure rigidity. The observable optimum pH and temperature for PCL@MCNC were higher than those of free PCL. PCL@MCNC manifested relatively higher enzyme-substrate affinity and catalytic efficiency. Moreover, PCL@MCNC was capable of effectively catalyzing asymmetric hydrolysis of ketoprofenethyl ester with high yield of 43.4% and product e.e. of 83.5%. Besides, immobilization allowed PCL@MCNC reuse for at least 6 consecutive cycles retaining over 66% of its initial activity. PCL@MCNC was readily recycled by magnetic forces. Remarkably, the as-prepared nanobiocatalyst PCL@MCNC is promising for biocatalysis.
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Ren H, Zong MH, Wu H, Li N. Efficient Pretreatment of Wheat Straw Using Novel Renewable Cholinium Ionic Liquids To Improve Enzymatic Saccharification. Ind Eng Chem Res 2016. [DOI: 10.1021/acs.iecr.5b03729] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wei P, Liang J, Cheng J, Zong MH, Lou WY. Markedly improving asymmetric oxidation of 1-(4-methoxyphenyl) ethanol with Acetobacter sp. CCTCC M209061 cells by adding deep eutectic solvent in a two-phase system. Microb Cell Fact 2016; 15:5. [PMID: 26758368 PMCID: PMC4711044 DOI: 10.1186/s12934-015-0407-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Accepted: 12/30/2015] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Enantiopure (S)-1-(4-methoxyphenyl) ethanol {(S)-MOPE} can be employed as an important synthon for the synthesis of cycloalkyl [b] indoles with the treatment function for general allergic response. To date, the biocatalytic resolution of racemic MOPE through asymmetric oxidation in the biphasic system has remained largely unexplored. Additionally, deep eutectic solvents (DESs), as a new class of promising green solvents, have recently gained increasing attention in biocatalysis for their excellent properties and many successful examples in biocatalytic processes. In this study, the biocatalytic asymmetric oxidation of MOPE to get (S)-MOPE using Acetobacter sp. CCTCC M209061 cells was investigated in different two-phase systems, and adding DES in a biphasic system was also explored to further improve the reaction efficiency of the biocatalytic oxidation. RESULTS Of all the examined water-immiscible organic solvents and ionic liquids (ILs), 1-butyl-3-methylimidazolium hexafluorophoshpate ([C4MIM][PF6]) afforded the best results, and consequently was selected as the second phase of a two-phase system for the asymmetric oxidation of MOPE with immobilized Acetobacter sp. CCTCC M209061 cells. For the reaction performed in the [C4MIM][PF6]/buffer biphasic system, under the optimized conditions, the initial reaction rate, the maximum conversion and the residual substrate e.e. recorded 97.8 μmol/min, 50.5 and >99.9 % after 10 h reaction. Furthermore, adding the DES [ChCl][Gly] (10 %, v/v) to the aqueous phase, the efficiency of the biocatalytic oxidation was rose markedly. The optimal substrate concentration and the initial reaction rate were significantly increased to 80 mmol/L and 124.0 μmol/min, respectively, and the reaction time was shortened to 7 h with 51.3 % conversion. The immobilized cell still retained over 72 % of its initial activity after 9 batches of successive reuse in the [C4MIM][PF6]/[ChCl][Gly]-containing buffer system. Additionally, the efficient biocatalytic process was feasible up to a 500-mL preparative scale. CONCLUSION The biocatalytic asymmetric oxidation of MOPE with Acetobacter sp. CCTCC M209061 cells was successfully conducted in the [C4MIM][PF6]-containing biphasic system with high conversion and enantioselectivity, and the reaction efficiency was further enhanced by adding [ChCl][Gly] to the reaction system. The efficient biocatalytic process was promising for the preparation of enantiopure (S)-MOPE.
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Yang FX, Xu P, Yang JG, Liang J, Zong MH, Lou WY. Efficient separation and purification of anthocyanins from saskatoon berry by using low transition temperature mixtures. RSC Adv 2016. [DOI: 10.1039/c6ra22912c] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Separation of anthocyanins from saskatoon berry by using low transition temperature mixtures.
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Wen P, Zhu DH, Wu H, Zong MH, Jing YR, Han SY. Encapsulation of cinnamon essential oil in electrospun nanofibrous film for active food packaging. Food Control 2016. [DOI: 10.1016/j.foodcont.2015.06.005] [Citation(s) in RCA: 191] [Impact Index Per Article: 23.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Wen P, Zhu DH, Feng K, Liu FJ, Lou WY, Li N, Zong MH, Wu H. Fabrication of electrospun polylactic acid nanofilm incorporating cinnamon essential oil/β-cyclodextrin inclusion complex for antimicrobial packaging. Food Chem 2015; 196:996-1004. [PMID: 26593582 DOI: 10.1016/j.foodchem.2015.10.043] [Citation(s) in RCA: 190] [Impact Index Per Article: 21.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2015] [Revised: 10/08/2015] [Accepted: 10/10/2015] [Indexed: 02/07/2023]
Abstract
A novel antimicrobial packaging material was obtained by incorporating cinnamon essential oil/β-cyclodextrin inclusion complex (CEO/β-CD-IC) into polylacticacid (PLA) nanofibers via electrospinning technique. The CEO/β-CD-IC was prepared by the co-precipitation method and SEM and FT-IR spectroscopy analysis indicated the successful formation of CEO/β-CD-IC, which improved the thermal stability of CEO. The CEO/β-CD-IC was then incorporated into PLA nanofibers by electrospinning and the resulting PLA/CEO/β-CD nanofilm showed better antimicrobial activity compared to PLA/CEO nanofilm. The minimum inhibitory concentration (MIC) of PLA/CEO/β-CD nanofilm against Escherichia coli and Staphylococcus aureus was approximately 1 mg/ml (corresponding CEO concentration 11.35 μg/ml) and minimum bactericidal concentration (MBC) was approximately 7 mg/ml (corresponding CEO concentration 79.45 μg/ml). Furthermore, compared with the casting method, the mild electrospinning process was more favorable for maintaining greater CEO in the obtained film. The PLA/CEO/β-CD nanofilm can effectively prolong the shelf life of pork, suggesting it has potential application in active food packaging.
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Wang ZY, Bi YH, Yang RL, Duan ZQ, Nie LH, Li XQ, Zong MH, Wu J. The halo-substituent effect on Pseudomonas cepacia lipase-mediated regioselective acylation of nucleosides: A comparative investigation. J Biotechnol 2015; 212:153-8. [PMID: 26325198 DOI: 10.1016/j.jbiotec.2015.08.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2015] [Revised: 08/27/2015] [Accepted: 08/28/2015] [Indexed: 11/19/2022]
Abstract
In this work, comparative experiments were explored to investigate the substrate specificity of Pseudomonas cepacia lipase in regioselective acylation of nucleosides carrying various substituents (such as the H, F, Cl, Br, I) at 2'- and 5-positions. Experimental data indicated that the catalytic performance of the enzyme depended very much on the halo-substituents in nucleosides. The increased bulk of 2'-substituents in ribose moiety of the nucleoside might contribute to the improved 3'-regioselectivity (90-98%, nucleosides a-d) in enzymatic decanoylation, while the enhancement of regioselectivity (93-99%) in 3'-O-acylated nucleosides e-h could be attributable to the increasing hydrophobicity of the halogen atoms at 5-positions. With regard to the chain-length selectivity, P. cepacia lipase displayed the highest 3'-regioselectivity toward the longer chain (C14) as compared to shorter (C6 and C10) ones. The position, orientation and property of the substituent, specific structure of the lipase's active site, and acyl structure could account for the diverse results.
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An YX, Zong MH, Wu H, Li N. Pretreatment of lignocellulosic biomass with renewable cholinium ionic liquids: Biomass fractionation, enzymatic digestion and ionic liquid reuse. BIORESOURCE TECHNOLOGY 2015; 192:165-171. [PMID: 26026293 DOI: 10.1016/j.biortech.2015.05.064] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 05/18/2015] [Accepted: 05/19/2015] [Indexed: 06/04/2023]
Abstract
Pretreatment of lignocelluloses is a key step in the biorefinery for production of biofuels and valuable platform chemicals. In this work, various lignocelluloses were pretreated using cholinium ionic liquids (ILs) that are wholly composed of biomaterials, and fractionated into carbohydrate-rich materials (CRMs) and lignin-rich materials (LRMs). Cholinium ILs were found to be effective pretreatment solvents for grass lignocelluloses as well as eucalyptus, resulting in significant improvements in the glucose yields (58-75%) in subsequent enzymatic hydrolysis, while they were inefficient to make pine susceptible to biodegradation. Approximately 46% of lignin in native rice straw was fractionated as LRM after pretreatment using cholinium argininate ([Ch][Arg]). [Ch][Arg] showed excellent recyclability, and the total recovery was as high as 75% after reused for 8 cycles. Besides, rice straw pretreated by the recycled IL remained highly digestible, and good glucose yields (63-75%) were achieved after its enzymatic hydrolysis.
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Wei P, Xu P, Wang XT, Lou WY, Zong MH. Asymmetric reduction of ethyl acetoacetate catalyzed by immobilized Acetobacter sp. CCTCC M209061 cells in hydrophilic ionic liquid hybrid system. BIOTECHNOL BIOPROC E 2015. [DOI: 10.1007/s12257-014-0751-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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100
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Hu TG, Cheng JH, Zhang BB, Lou WY, Zong MH. Immobilization of Alkaline Protease on Amino-Functionalized Magnetic Nanoparticles and Its Efficient Use for Preparation of Oat Polypeptides. Ind Eng Chem Res 2015. [DOI: 10.1021/ie504691j] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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