Journal of Molecular Catalysis B Enzymatic (J MOL CATAL B-ENZYM )

Publisher: Elsevier

Journal description

The journal is an international forum devoted to research and developments in the applications of whole-cell and cell-free enzymes as catalysts in organic synthesis. Emphasis is focused on mechanistic and synthetic aspects of the biocatalytic transformation.Papers deal with the following topics; Industrial applications of enzymatic processes, e.g. in fine chemical synthesis; Chemo-, regio- and enantioselective transformations; Screening for biocatalysts; Integration of biocatalytic and chemical steps in organic syntheses; Novel biocatalysts, e.g. enzymes from extremophiles and catalytic antibodies; Enzyme immobilization and stabilization, particularly in non-conventional media; Bioprocess engineering aspects, e.g. membrane bioreactors; Improvement of catalytic performance of enzymes, e.g. by protein engineering or chemical modification; Structural studies, including computer simulation, relating to substrate specificity and reaction selectivity; Biomimetic studies related to enzymatic transformations.

Current impact factor: 2.75

Impact Factor Rankings

2015 Impact Factor Available summer 2015
2013 / 2014 Impact Factor 2.745
2012 Impact Factor 2.823
2011 Impact Factor 2.735
2010 Impact Factor 2.33
2009 Impact Factor 2.4
2008 Impact Factor 2.015

Impact factor over time

Impact factor
Year

Additional details

5-year impact 2.81
Cited half-life 5.60
Immediacy index 0.54
Eigenfactor 0.01
Article influence 0.60
Website Journal of Molecular Catalysis B: Enzymatic website
Other titles Journal of molecular catalysis
ISSN 1873-3158
OCLC 39177340
Material type Document, Periodical, Internet resource
Document type Internet Resource, Computer File, Journal / Magazine / Newspaper

Publisher details

Elsevier

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    • Author can archive a post-print version
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    • Deposit due to Funding Body, Institutional and Governmental policy or mandate only allowed where separate agreement between repository and the publisher exists.
    • Permitted deposit due to Funding Body, Institutional and Governmental policy or mandate, may be required to comply with embargo periods of 12 months to 48 months .
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    • Publisher's version/PDF cannot be used
    • Articles in some journals can be made Open Access on payment of additional charge
    • NIH Authors articles will be submitted to PubMed Central after 12 months
    • Publisher last contacted on 18/10/2013
  • Classification
    ​ green

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: Biotransformation of artemisinin (1) with the selected hairy root clones of three medicinally important plants, i.e., Atropa belladonna, Hyoscyamus muticus and Ocimum basilicum, yielded two biotransformed products, which were identified as 3-α-hydroxy-1-deoxyartemisinin (2) and 4-hydroxy-9,10-dimethyloctahydrofuro-(3,2-i)-isochromen-11(4H)-one (3). Their structures were elucidated through spectroscopic analysis (NMR/MS) and X-ray crystallography. The relative transformation efficiencies of the tested hairy root clones differed concerning individual bioconversion reactions. Consequently, the HR clones of H. muticus and A. belladonna accomplished the highest conversion of (1) to (2) and (3) respectively, while that of O. basilicum imparted an intermediate response. In-silico and in-vitro bioactivity analysis of the derivatives revealed promising anti-plasmodial activity profile in tandem with notable TNF level lowering potential of compound (2), indicating thereby its prospective therapeutic merit in ameliorating the severity of malarial infection.
    Journal of Molecular Catalysis B Enzymatic 03/2015; 113.
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    ABSTRACT: Cost-effective application of lignocellulolytic enzymes holds the key towards commercialization of enzymatic hydrolysis of lignocellulosic biomass. Carrier free immobilization of enzyme(s) offers a lucrative prospect. Combined-cross linked enzyme aggregates (combi-CLEAs) are a novel prospective and this present study addresses the preparation, characterization and application of xylanase-mannanase combi-CLEAS on lime-preteated sugarcane bagasse and milled corn stover. X6-CLEAs, X7-CLEAs, L1-CLEAs and L7-CLEAs were prepared after elaborative optimization of the precipitating agent and glutaraldehyde concentration. The highest activity after precipitation was observed with acetone but following cross-linking with glutaraldehyde less than 60% activity was retained, while more than 60% activity was retained after precipitation with ammonium sulphate and cross-linking with glutaraldehyde. Accessory enzyme activities including α-arabinofuranosidase, β-xylosidase, esterases, β-mannosidase, α-galactosidase and β-glucosidase) were also determined. More than an1.5 fold increase in thermostability compared to the free enzyme was observed over a broad temperature range (50-70 °C). Tri-synergy studies and quad synergy studies were used to generate combi-CLEAs with different protein ratios. Hydrolysis of lime pre-treated bagasse with combi-CLEAs at protein ratios corresponding to X6(33.0%): X7(17.0%): L1 (17.0%): L7 (33.0%) resulted in a 1.68 fold higher sugar release compared to the quad synergy model using free enzymes. Similarly, hydrolysis of corn stover with combi-CLEAs at protein ratios corresponding to X6 (40.0%): X7(10.0%): L1 (10.0%): L7 (40.0%) resulted in a 1.58 fold higher sugar release compared to the sugar release observed with the quad synergy model using free enzymes. Monomeric sugars constituted 70-75% of reducing sugars released during hydrolysis. The role of accessory enzymes in improving enzyme synergy was clearly shown. The efficiency of combi-CLEAs compared to free enzymes makes them ideal candidates for the prudent and cost-effective commercialization of lignocellulolytic enzymes.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Enzyme hyperactivation using a complementary charged modulator/substrate pair has potential for enzyme applications in a wide range of research fields. Here, we report that amine compounds as well as naturally occurring polyamines, putrescine, spermidine, and spermine, enhance the enzyme activity of α-chymotrypsin (ChT) toward anionic substrates. The enzyme activity of ChT was increased by 1.6–6.9-fold in the presence of 50 mM amine compounds at pH 7.5. Analysis of the enzyme kinetics indicated that the catalytic constant (kcat) and specific constant (kcat/KM) increased in the presence of amine compounds depending on both the multivalency and hydrophobicity of the amine compounds, whereas the Michaelis constant (KM) remained constant. Molecular dynamics simulation suggested that the enhancement of enzyme activity of ChT was induced by weak interactions between amine compounds and ChT. These results provide extended design parameters for artificial activators for enzyme hyperactivation as well as an understanding of enzyme activity in the crude complex condition in vivo.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Multipoint covalent attachment of Rhizopus oryzae lipase (ROL) on epoxy-functionalized silica and silica nanoparticles (MCM-41 and SBA-15) is reported. Multipoint immobilization of enzymes on these supports usually performs by the reaction between several epoxy groups of the support and several Lys residues on the external surface of the enzyme molecules at pH 10. However, this standard immobilization procedure is unsuitable for ROL due to the low stability of ROL at pH 10. Introducing new amino groups with lower pKb to the surface of ROL by using chemical amination strategy permits immobilization of the enzyme at lower pH values. Immobilization/stabilization of aminated ROL was performed in two steps. First the enzyme is covalently immobilized at pH 7.0 and then the already immobilized enzyme is further incubated at pH 9.2 to promote the formation of further covalent linkages between the immobilized ROL and the support. The results showed higher thermal and co-solvent stability for immobilized derivatives of aminated ROL compared to the results obtained for the derivatives of not-aminated ROL and free ROL. Influence of the immobilization procedure on selectivity of the immobilized preparations was studied in selective hydrolysis of fish oil at three different conditions. The selectivity and reusability of ROL was greatly improved after immobilization. All the derivatives discriminate between cis-5,8,11,14,17-eicosapentaenoic acid (EPA) and cis-4,7,10,13,16,19-docosahexaenoic acid (DHA) in favor of EPA.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Immobilization of enzymes has been considered as an efficient approach to facilitate enzyme recovery and to improve biocatalyst stability. However, multimeric nucleoside phosphorylases, useful for the synthesis of modified nucleosides, encounter several challenges to their immobilization, including requirement for high enzymatic load, and poor retention of enzyme activity. In this study, multimeric enzymes pyrimidine nucleoside phosphorylase (PyNP) and purine nucleoside phosphorylase (PNP), from Thermus thermophilus and Geobacillus thermoglucosidasius, respectively, were successfully immobilized on the magnetic beads with cross-linked polyethyleneimine and epoxide functional groups, resulting in high enzyme loading (up to 0.4 and 1.3 g per g dry beads), high enzyme activity maintenance (41% and 83% under the highest enzyme loading), and improved enzyme stability. The screening of the immobilization conditions showed that binding buffer pH, enzyme loading amount, binding temperature and binding time are important factors for the immobilization yield. The application of the immobilized enzymes in the synthesis of 2,6-dihalogenated purine nucleosides achieved with high substrate conversion (78.5 - 85.5%) as well as high productivity (1.5 -2.0 g L−1 h−1).
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Given the importance of β-alanine, the nitrilase BjNIT3397 from Bradyrhizobium japonicum strain USDA110 was examined toward the hydrolysis of 3-aminopropionitrile. It has been found that nitrilase BjNIT3397 effectively hydrolyzed 3-aminopropionitrile with substrate concentration up to 3 M (210 g/L) at the pH 7.3 and temperature 30°C. With the increase of substrate concentration from 0.6 M to 3 M, 3-aminopropanamide was formed and its percentage in the products was increased up to 33%. In order to reduce the formation of 3-aminopropanamide, aspartate ammonia-lyase and fumaric acid were added into the reaction system to consume the byproduct ammonia. As expected, the reaction was shifted toward the formation of β-alanine, resulting in the decrease of 3-aminopropanamide from 33% to 3%. Therefore, a tandem reaction strategy was developed to effectively prevent the formation of 3-aminopropanamide. This might also offer a possibility of producing β-alanine and L-aspartic acid in one process.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: The aim of this study was to purify and characterize the lipase produced by Burkholderia sp. EQ3 a bacterium isolated from the wastewater pond of a canned fish factory. The lipase was purified to homogeneity with a 70-fold increase in its activity by chilled acetone precipitation, Q-Sepharose Fast Flow and Sephadex G-50 column chromatography, respectively. The molecular mass of the purified lipase was 30.7 kDa. The purified lipase showed optimal activity at pH 7.0-7.5 and 30 °C. The enzyme was stable over the pH range of 5.0-8.0 and temperatures of between 30-55 °C for 1 h. Its half-life was 2 h at 55 °C. The lipase activity was enhanced in the presence of Ca2+, Mg2+ and K+ while it was inactivated by Cu2+, Fe2+ and Zn2+. It hydrolyzed the natural triglycerides with its highest activity on coconut oil (120%), olive oil (101%) and palm olein (100%). Gum arabic (1%) significantly increased the lipase activity whereas 1.0 mM phenyl methyl sulphonyl fluoride strongly reduced the activity. The purified lipase EQ3 retained 80% activity in iso-propanol, but was inactivated by ethanol and iso-octane as well as other hydrophobic solvents. The lipase EQ3 was immobilized by adsorption with Accurel MP-100 and used for wax esters synthesis and compared with five commercial immobilized lipases (Lipozyme RM IM, Lipozyme TL IM, Novozyme 435, Lipase PS and Lipase AK). The transesterification reaction was carried out between coconut oil, palm olein and jatropha oil with oleyl alcohol by using 1 U of enzyme, a substrate molar ratio of oil and oleyl alcohol of 1:3 in hexane at 37 °C and 150 rpm for 72 h. The immobilized lipase EQ3 was most efficient in the synthesis of wax esters with 60.3, 49.6 and 50.1% wax esters from coconut oil, palm olein and jatropha oil, respectively. For the five commercial immobilized lipases, Lipozyme RM IM exhibited the highest wax esters synthesis with 49.2, 41.4 and 48.1% wax esters, respectively.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Cytochrome P450SMO from Rhodococcus sp. ECU0066 is a natural self-sufficient P450 monooxygenase, consisting of a heme domain, a flavin-reductase domain containing FMN and NADPH binding sites, and a [Fe2S2] ferredoxin domain. P450cam catalyzes the hydroxylation of camphor to 5-exo-hydroxycamphor. The variant P450cam (Y96F/V247L) was reported for the oxidation of monoterpene by protein engineering. In this work, we constructed an artificial self-sufficient P450-type monoterpene hydroxylase by connecting the P450SMO reductase domain and the P450cam (Y96F/V247L) domain together with a linker region (G4S)4. The resultant chimeric P450 enzyme could catalyze the hydroxylation of (-)-limonene and α-pinene as well as camphor, which were all inactive for the natural fusion protein P450SMO. Co-expression of the fused P450 with a glucose dehydrogenase (GDH) improved the (-)-limonene conversion as sufficient NADPH was regenerated in the system with glucose as a cosubstrate. This work illustrated that P450SMO reductase might act as an electron donor partner of P450s and might be used for fusion with heterogeneous P450 domains to elucidate the catalytic function of other unknown P450s.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Aliphatic diamines have been used as chemical reagents for the monomers of polyamides (i.e., Nylon 46, Nylon 510, Nylon 66, Nylon 610 and so on), and can be made from lysine, arginine or ornithine by the metabolism of microbes through decarboxylases. However, the conventional derivatization methods for the HPLC-based quantitative analysis of aliphatic diamines exhibit poor sensitivity and efficiency for the monitoring of enzyme activity. In this study, a chemical derivatization method using diethyl ethoxymethylenemalonate (DEEMM) was applied to monitor lysine decarboxylase activity for the production of cadaverine by measuring the levels of intracellular and secreted lysine and cadaverine. The calibration graphs for the determination of 2,4-diaminobutyrate, 2,6-diaminopimelic acid, ornithine, arginine, lysine, 1,3-diaminopropane, putrescine dihydrochloride, cadaverine, hexamethylenediamine, and 1,7-diaminoheptane were measured by the highly sensitive method using DEEMM, and a linear relationship was observed for each dimaine compound, with limits of detection up to 0.001 mM. Application of this method will be useful for the sensitive monitoring of lysine decarboxylase reactions through the detection of substrates containing amine groups and products with diamines using HPLC and a UV detector.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Link Free download: http://authors.elsevier.com/a/1Qdg34w1w6ownF (1D)-γ-Al2O3 nanorods (Al-nR) were synthesized, thermally treated and characterized by a variety of techniques. This material was used for chloroperoxidase (CPO) enzyme immobilization by physical adsorption and then assayed for the biocatalytic oxidation of dibenzothiophene (DBT). The textural properties of Al-nR nanostructured materials were successfully tuned to perform the CPO immobilization. The nanostructures exhibited a good stability throughout the thermal treatments since its crystallinity remained unchanged and the nanorods arrays were detected in all materials by XRD and HRTEM. A great affinity between the CPO and the nanorods was observed, due to favorable electrostatic interactions during the immobilization process. A remarkable increase on the dibenzothiophene oxidative biotransformation activity of immobilized CPO was obtained when compared with the free CPO. The morphological and textural properties of Al-nR-T material enhanced the enzymatic transformation of dibenzothiophene to form the sulfoxide derivative, especially when the Al–nR-700 °C material was used. The CPO + Al-nR-700 °C preparation exhibited almost twice the activity of the free CPO enzyme. The main product under our experimental conditions was DBT-sulfoxide. The potential application of biocatalytic nanorods for a fuel desulfurization process is discussed.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Novel surfactant activated magnetic cross-linked enzyme aggregates of Thermomyces lanuginosus lipase (TLL-magnetic-CLEAs) were developed and provided an efficient approach to improving the activity and stability of lipase for biodiesel production. In the methanolysis of jatropha oil for biodiesel synthesis, the maximum yield in isopropyl ether was 88% after 48 h at 40 °C, representing 3.5-fold and 2.5-fold higher activity than that exhibited by free TLL and TLL CLEAs, respectively. Moreover, Tween 80-activated TLL-magnetic-CLEAs retained their activity during storage at 4 °C for eleven weeks and ten cycles of repeated 48 h biodiesel reactions at 40 °C (over 30 days). Additionally, the surface morphology, particle size and loading of lipase aggregates were confirmed by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The combination of interfacial activation, high specific enzyme activity, improved stability and easy recovery of magnetic CLEAs presents an attractive process for lipase immobilization and provides a promising catalyst for biodiesel production.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: Staphylococcus haemolyticus L62 lipase is methanol-stable enzyme and its functional expression has been performed in Escherichia coli cells. The recombinant lipase L62 was immobilized on amine-magnetic microparticles (AMPs) by protein precipitation and covalent cross-linking methods. The physical properties of L62-AMP were evaluated by electron microscopy, a zeta potential system, and magnetic property measurement system. L62-AMPs had diameters of about a 1.6 μm size and displayed a saturation magnetic value of 25.56 A·m2/kg. In comparison with free lipase L62, L62-AMP showed high optimum temperature and high activity at a wide pH range. L62-AMP showed high hydrolytic activity toward tributyrin and olive oil among various triglycerides. L62-AMP was recovered within 2 min with Neodymium magnet and maintained > 90% residual activity after 4 recoveries. L62-AMP was used to produce fatty acid methyl ester (FAME) using methanol and olive oil with molar ratio of 6:1. By one step-transesterification reaction, the yield of FAME was about 86.4% after a 24 h reaction at 30 °C.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: In this study, we investigated the use of insects as biocatalysts for the biotransformation of monoterpenoids such as (+)-(1R,2S,4R)-borneol (1) and (−)-(1S,2R,4S)-borneol (2) by the larvae of Spodoptera litura. The substrates were administrated to the fourth instar larvae of S. litura through food, and the metabolites were collected in the faeces. Analysis showed that substrate 1 was converted into the following 12 metabolites: (+)-(1R,2S,4R)-borneol linoleate (1-1), (+)-(1R,2S,4R)-borneol linolenate (1-2), (+)-(1R,2S,4R)-borneol-2-O-β-D-glucopyranoside (1-3), (+)-(1R,2S,4R,5S)-5-endo-hydroxyborneol (1-4), (+)-(1R,4R,5S)-5-endo-hydroxycamphor (1-5), (+)-(1R,2S,4R,5R)-5-exo-hydroxyborneol (1-6), (+)-(1R,4R,5R)-5-exo-hydroxycamphor (1-7), (+)-(1R,2S,4R,7R)-8-hydroxyborneol (1-8), (+)-(1R,4R,7R)-8-hydroxycamphor (1-9), (+)-(1R,2S,4R,7S)-9-hydroxyborneol (1-10), (+)-(1R,2S,4R)-10-hydroxyborneol (1-11), and (+)-(1R,2R,3S,4S)-3-endo-hydroxyborneol (1-12). The metabolism of substrate 2 generated 12 enantiomers of the above metabolites, namely 2-1 to 2-12. Compounds 1-1, 1-2, 1-3, 2-1, 2-2, 2-8, 2-10, and 2-12 are novel compounds. The main metabolites were generated by phase II reactions such as esterification or glucosidation of the parent substrates. The minor metabolites originated from phase I reactions such as hydroxylation or oxidation, probably by cytochrome P450 enzymes. These fatty acid and glucose conjugation reactions are new metabolic pathways, compared with those reported in previous studies on monoterpenoids in S. litura.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: A new carboxylic acid reductase (CAR) gene from Segniliparus rotundus DSM 44985 was overexpressed in E. coli. The recombinant enzyme exhibited high activity toward a variety of aromatic and aliphatic carboxylic acids. Especially, it effectively reduced 4-hydroxybenzoic acid (8a) and 4-nitrobenzoic acid (19a), toward which the known Nocardia CAR exhibited no or little activity. The recombinant E. coli cells co-expressing the Segniliparus CAR and Nocardia PPTase genes catalyzed the reductions of vanillic acid (20a) and 3, 4-dihydroxyphenylacetic acid (25a) to give vanillyl alcohol (20c) and 3-hydroxytyrosol (25c) with high yield, respectively. The endogenous aldehyde reductases of E. coli should be responsible for the further reduction of the produced aldehydes. These results demonstrated that Segniliparus CAR was a useful addition to the biocatalyst tool-box for the reduction of carboxylic acids and might find applications in the synthesis of valuable bio-based chemicals from renewable resources.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: An H1004A-C1006S variant of Aspergillus nidulans diol synthase was identified as an 8-dioxygenase. Whole recombinant Escherichia coli cells expressing the double-site variant showed highest activity for converting linoleic acid to 8-hydroperoxy-9,12(Z,Z)-octadecadienoic acid (8-HPODE), which in turn was reduced to 8-hydroxy-9,12(Z,Z)-octadecadienoic acid (8-HODE) by the addition of a reducing agent. The optimization of 8-HPODE production was performed by response surface methodology, and the optimal conditions were pH 8.3, 27.2 °C, 22.7% dimethyl sulfoxide, 27.0 g l−1 cells, and 16.5 g l−1 linoleic acid in a 100 ml baffled flask containing a 10 ml reaction mixture with agitation at 236 rpm. The reduction of 8-HPODE to 8-HODE was highest when Tris (2-carboxyethyl) phosphine hydrochloride (TECP-HCl) was added at a final concentration of 25 mM. Under the optimized reaction and reduction conditions, whole cells expressing H1004A-C1006S variant of A. nidulans diol synthase produced 5.0 g l−1 8-HODE for 1 h without the formation of di-hydroxy fatty acids. This is the first report of the biotechnological production of 8-HODE.
    Journal of Molecular Catalysis B Enzymatic 02/2015;
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    ABSTRACT: The microbial transformation of Astragalus sp. derived sapogenins, namely cycloastragenol, astragenol and cyclocanthogenol, by Cunninghamella blakesleeana NRRL 1369 and Glomerella fusarioides ATCC 9552 were investigated. The unique enzyme system of both fungi resulted hydroxylation, cyclization, dehydrogenation and oxidation reactions. Structures of the new metabolites were elucidated by 1-D (1H, 13C, NOESY), 2-D NMR (DQF-COSY, HMBC, HMQC, NOESY) and HR-MS analyses.
    Journal of Molecular Catalysis B Enzymatic 01/2015;
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    ABSTRACT: Lipase-based catalysts were tested for the ring-opening polymerization of D-, L- and D,L-lactide isomers, highlighting the different specificity of the enzyme toward these isomers. Free form of Candida antarctica lipase B (CALB) and its clay- and acrylic resin- immobilized forms were compared. For L- and D,L-lactide monomers only short oligomers were obtained. The acrylic resin immobilized form of CALB (NOVO-435) led to a complete conversion of D-lactide to PDLA with a Mn of 2|600 g/mol, whereas the clay-immobilized and free forms of CALB exhibited slower kinetics and produced chains of lower Mn. Copolymerization reactions between ɛ-caprolactone and lactide isomers were performed using NOVO-435 as bio-catalyst. Random copolyesters were successfully synthesized by copolymerizing D-lactide with ɛ-caprolactone. Better results were obtained with a two-step reaction, starting from presynthesized polycaprolactone chains, compared with the one-pot copolymerization. Conducting this two-step copolymerization in the presence of organo-modified montmorillonite allowed the successful synthesis of copolymer/clay nanohybrids.
    Journal of Molecular Catalysis B Enzymatic 01/2015;
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    ABSTRACT: Strains of Ganoderma lucidum MDU-7 produces multiple extracellular isoforms of laccase in submerged culture condition using malt extract as a carbon source and copper sulfate as an inducer. SDS- PAGE followed by MALDI-TOF peptide fingerprinting confirmed laccase isozyme with molecular mass of 24-66 kDa. Two laccase isozymes (Glac H1 and Glac L1) were purified from native-PAGE protein purification method and a comparative catalytic and antioxidant study has been performed. Both of the laccase isozymes have optimum temperature and pH at 50 °C and 4.0, respectively. Glac L1 has higher stability in comparison to Glac H1, over wide range of temperature, pH, divalent metal ions and surfactants. The Km values of Glac L1 and Glac H1 determined for guaiacol, ABTS and O-tolidine were 98 μM, 26 μM, 320 μM and 281 μM, 29 μM, 338 μM, respectively. Glac H1, irrespective to its laccase activity and stability, act as a better antioxidant than Glac L1.
    Journal of Molecular Catalysis B Enzymatic 01/2015; 15.
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    ABSTRACT: A lipase from Rhizopus oryzae (rProROL) was produced by recombinant Pichia pastoris in high productivity with a maximum lipase activity of 15,900 U/mL, and was employed to hydrolyze soybean oil for the production of diacylglycerol (DAG).
    Journal of Molecular Catalysis B Enzymatic 01/2015;