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Davis, Benjamin G.; Boyer, Viviane

doi:10.1039/b003667f

Cited by 175 publications

(10 citation statements)

References 347 publications

(232 reference statements)

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Section: Introductionmentioning

confidence: 99%

“…The implementation of enzymes in synthetic chemistry is often viewed as very lucrative because of their high catalytic activity, substrate specificity, stereo- and regiospecificity, and lack of byproducts. , Among enzymes currently attracting significant interest is laccase, a benzenediol:oxygen oxidoreductase containing a multicopper core. , Having a broad substrate specificity, laccase plays a multifaceted role in biological synthesis including pigment formation, lignin degradation, and cellular repair . Synthetically, laccases are well-known for their ability to polymerize phenol and phenol derivatives via oxidizing the phenol substrate with the concomitant reduction of oxygen to water. , This polymerization occurs through the production of phenoxy radicals which can then undergo C–C or C–O coupling at the ortho- and/or para-position.…”

Section: Introductionmentioning

confidence: 99%

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Polymer-Assisted Biocatalysis: Effects of Macromolecular Architectures on the Stability and Catalytic Activity of Immobilized Enzymes toward Water-Soluble and Water-Insoluble Substrates

Scheibel

Gitsov

2018

ACS Omega

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The aim of this study is to develop efficient enzyme immobilization media that will enable the reuse of the biocatalysts over multiple cycles, increase their thermal stability, and attenuate their activity toward hydrophobic substrates for “green” transformations in aqueous media. For this purpose, amphiphilic AB and ABA block copolymers were synthesized and tested with laccase (a multicopper oxidase). In all cases, the hydrophilic B block consisted of poly(ethylene glycol), PEG, with molecular masses of 3, 5, 13, 20, or 13 kDa poly(ethylene oxide). The hydrophobic A blocks were made of linear poly(styrene), PS; hyperbranched poly(p-chloromethyl styrene); or dendritic poly(benzyl ether)s of generations 2, 3, and 4 (G2, G3, and G4) with molecular masses ranging from 1 to 24 kDa. A total of 23 different copolymers (self-assembling into micelles or physical networks) were evaluated. Notable activity enhancements were achieved with both micelles (up to 253%) and hydrogels (up to 408%). The highest enzymatic activity and thermal stability were observed with laccase immobilized in hydrogels consisting of the linear ABA block copolymer PS2.7k–PEG3k–PS2.7k (13 290 μkat/L, 65 °C, ABTS test). This represents a 1245% improvement over native laccase at the same conditions. At 25 °C, the same complex showed a 1236% higher activity than the enzyme. The highest polymerization yield for a water-insoluble monomer was achieved with laccase immobilized in hydrogels composed of linear–dendritic ABA copolymer G3–PEG5k–G3 (85.5%, 45 °C, tyrosine monomer). The broad substrate specificity and reusability of the immobilized laccase were also demonstrated by the successful discoloration of bromophenol blue, methyl orange, and rhodamine B over eight repetitive cycles.

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Polymer-Assisted Biocatalysis: Effects of Macromolecular Architectures on the Stability and Catalytic Activity of Immobilized Enzymes toward Water-Soluble and Water-Insoluble Substrates

Scheibel

Gitsov

2018

ACS Omega

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“…The lipase-catalyzed enzymatic synthesis of sugar esters has been studied in the last two decades as an alternative to conventional chemical synthesis, offering the usual advantages of enzyme biocatalysis, namely high specificity and moderate reaction conditions (Ferrer et al 2005). The low solubility of sugar esters in water and the requirement of low water activity to drive the reaction towards synthesis makes necessary the use of non-conventional reaction media (Ballesteros et al 1995;Davis and Boyer, 2001): Organic solvents (Chamouleau et al 2001;Reyes-Duarte et al 2005), supercritical fluids (Habulin et al 2008) and ionic liquids Roosen et al 2008). Lipases are structurally well conditioned to perform in such media and are the most used enzymes for sugar ester synthesis.…”

Section: Upgrading By Enzymatic Esterificationmentioning

confidence: 99%

Whey upgrading by enzyme biocatalysis

Illanes¹

2011

Electro Journal of Biotech

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Whey is a co-product of processes for the production of cheese and casein that retains most of the lactose content in milk. World production of whey is estimated around 200 million tons per year with an increase rate of about 2%/per year. Milk production is seasonal, so surplus whey is unavoidable. Traditionally, whey producers have considered it as a nuisance and strategies of whey handling have been mostly oriented to their more convenient disposal. This vision has been steadily evolving because of the upgrading potential of whey major components (lactose and whey proteins), but also because of more stringent regulations of waste disposal. Only the big cheese manufacturing companies are in the position of implementing technologies for their recovery and upgrading, so there is a major challenge in incorporating medium and small size producers to a platform of whey utilization, conciliating industrial interest with environmental protection within the framework of sustainable development. Within this context, among the many technological options for whey upgrading, transformation of whey components by enzyme biocatalysis appears as prominent. In fact, enzymes are green catalysts that can perform a myriad of transformation reactions under mild conditions and with strict specificity, so reducing production costs and environmental burden. This review pretends to highlight the impact of biocatalysis within a platform of whey upgrading. Technological options are shortly reviewed and then an in-depth and critical appraisal of enzyme technologies for whey upgrading is presented, with a special focus on newly developed enzymatic processes of organic synthesis, where the added value is high, being then a powerful driving force for industrial implementation.

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“…Enzymes are very useful catalysts for organic chemistry because they can be used in a wide range of reactions, and also because they show high reaction rates and selectivity [ 19 ]. Amongst the enzymes, lipases have been found to be particularly useful [ 20 , 21 ].…”

Section: Introductionmentioning

confidence: 99%

Chemoenzymatic Synthesis of the New 3-((2,3-Diacetoxypropanoyl)oxy)propane-1,2-diyl Diacetate Using Immobilized Lipase B from Candida antarctica and Pyridinium Chlorochromate as an Oxidizing Agent

Plata

Ruiz

et al. 2020

IJMS

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To exploit the hydrolytic activity and high selectivity of immobilized lipase B from Candida antarctica on octyl agarose (CALB-OC) in the hydrolysis of triacetin and also to produce new value-added compounds from glycerol, this work describes a chemoenzymatic methodology for the synthesis of the new dimeric glycerol ester 3-((2,3-diacetoxypropanoyl)oxy)propane-1,2-diyl diacetate. According to this approach, triacetin was regioselectively hydrolyzed to 1,2-diacetin with CALB-OC. The diglyceride product was subsequently oxidized with pyridinium chlorochromate (PCC) and a dimeric ester was isolated as the only product. It was found that the medium acidity during the PCC treatment and a high 1,2-diacetin concentration favored the formation of the ester. The synthesized compounds were characterized using IR, MS, HR-MS, and NMR techniques. The obtained dimeric ester was evaluated at 100 ppm against seven bacterial strains and two Candida species to identify its antimicrobial activity. The compound has no inhibitory activity against the bacterial strains used but decreased C. albicans and C. parapsilosis growth by 49% and 68%, respectively. Hemolytic activity was evaluated, and the results obtained support the use of the dimeric ester to control C. albicans and C. parapsilosis growth in non-intravenous applications because the compound shows hemolytic activity.

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Cited by 175 publications

References 347 publications

Polymer-Assisted Biocatalysis: Effects of Macromolecular Architectures on the Stability and Catalytic Activity of Immobilized Enzymes toward Water-Soluble and Water-Insoluble Substrates

Polymer-Assisted Biocatalysis: Effects of Macromolecular Architectures on the Stability and Catalytic Activity of Immobilized Enzymes toward Water-Soluble and Water-Insoluble Substrates

Whey upgrading by enzyme biocatalysis

Chemoenzymatic Synthesis of the New 3-((2,3-Diacetoxypropanoyl)oxy)propane-1,2-diyl Diacetate Using Immobilized Lipase B from Candida antarctica and Pyridinium Chlorochromate as an Oxidizing Agent

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