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lipase immobilization on epoxy-activated poly(vinyl acetate-acrylamide) microspheres.poly(vinyl acetate-acrylamide) microspheres with an average diameter of 2-4μm were successfully prepared and characterized via sem and ftir. then the microspheres were modified with epoxy groups through reacting with epichlorohydrin and used as carriers to covalently immobilize candida rugosa lipase. the results revealed that agitation played an important role on epoxy activation and the immobilization ratio increased with the increase of the epoxy density. on the other hand, the specific activi ...201525863711
enzymatic synthesis of aroma acetoin fatty acid esters by immobilized candida antarctica lipase b.to enzymatically synthesize aroma acetoin fatty acid esters, useful as flavor and fragrance ingredients in foods.201525851952
effect of the physicochemical properties of binary ionic liquids on lipase activity and stability.in the present study, the lipase-catalyzed hydrolysis of p-nitrophenyl butyrate is used as a model reaction to determine the activity and stability of candida rugosa lipase in binary ionic liquids (ils). the binary ils consist of hydrophobic 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim]pf6) and a small amount of hydrophilic 1-butyl-3-methylimidazolium nitrate ([bmim]no3) or 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([bmim]cf3so3) or 1-butyl-3-methylimidazolium tetrafluorobo ...201525841366
a facile enzymatic synthesis of geranyl propionate by physically adsorbed candida rugosa lipase onto multi-walled carbon nanotubes.in view of several disadvantages as well as adverse effects associated with the use of chemical processes for producing esters, alternative techniques such as the utilization of enzymes on multi-walled carbon nanotubes (mwcnts), have been suggested. in this study, the oxidative mwcnts prepared using a mixture of hno3 and h2so4 (1:3 v/v) were used as a supportive material for the immobilization of candida rugosa lipase (crl) through physical adsorption process. the resulting crl-mwcnts biocatalys ...201525837507
preparation of core-shell magnetic polydopamine/alginate biocomposite for candida rugosa lipase immobilization.a flexible, biocompatible and bioadhesive enzyme immobilizing material, which was synthesized based on the covalent assembly of biomimetic polymer and oxidized polysaccharide on magnetic nanoparticles (nps), has been developed in this feasibility study. in this work, the bio-inspired polymer, polydopamine (pda), was used to modify the well-monodispersed fe3o4 nps (mpda nps) with a controllable thickness via a dip-coating process, then the alginate di-aldehyde (ada) was covalently assembled on th ...201525784302
molecular dynamics investigation of the ionic liquid/enzyme interface: application to engineering enzyme surface charge.molecular simulations of the enzymes candida rugosa lipase and bos taurus α-chymotrypsin in aqueous ionic liquids 1-butyl-3-methylimidazolium chloride and 1-ethyl-3-methylimidazolium ethyl sulfate were used to study the change in enzyme-solvent interactions induced by modification of the enzyme surface charge. the enzymes were altered by randomly mutating lysine surface residues to glutamate, effectively decreasing the net surface charge by two for each mutation. these mutations resemble succiny ...201525641162
enzymatic synthesis of phytosterol esters catalyzed by candida rugosa lipase in water-in-[bmim]pf6 microemulsion.a water-in-ionic liquid microemulsion ([bmim]pf6/tween20/h2o) was applied as reusable reaction medium to esterify phytosterols with fatty acid by candida rugosa lipase (crl) successfully. two kinds of commercial crls, ay30 and ays which cannot effectively catalyze esterification in conventional reaction system were found effective in the microemulsion system. effects of reaction parameters on esterification were investigated; results showed that the conversion rate of 87.9 and 95.1 % was obtaine ...201525575761
high enantioselective novozym 435-catalyzed esterification of (r,s)-flurbiprofen monitored with a chiral stationary phase.lipases form candida rugosa and candida antarctica were tested for their application in the enzymatic kinetic resolution of (r,s)-flurbiprofen by enantioselective esterification. successful chromatographic separation with well-resolved peaks of (r)- and (s)-flurbiprofen and their esters was achieved in one run on chiral stationary phases by high-performance liquid chromatography (hplc). in this study screening of enzymes was performed, and novozym 435 was selected as an optimal catalyst for obta ...201525561056
hydrogen-bonding-driven enantioselective resolution against the kazlauskas rule to afford γ-amino alcohols by candida rugosa lipase.most lipases resolve secondary alcohols in accordance with the "kazlauskas rule" to give the r enantiomers. in a similar manner to other lipases, candida rugosa lipase (crl) exhibits r enantioselectivity towards heptan-2-ol, although the enantiomeric ratio (e) is low (e=1.6). however, unexpected enantioselectivity (i.e., s enantioselectivity, e=58) of crl towards 4-(tert-butoxycarbonylamino)butan-2-ol, which has a similar chain length to heptan-2-ol, has been observed. to develop a deeper unders ...201525477295
activation and deformation of immobilized lipase on self-assembled monolayers with tailored wettability.in this work, lipase from candida rugosa (crl) was immobilized on self-assembled monolayers (sams) with various wettabilities ranging from highly hydrophilic to highly hydrophobic by adsorption in order to clearly elucidate the interfacial activation character of lipases. the sams were made of 11-hydroxyundecane-1-thiol and 1-dodecanethiol. the adsorption behavior was monitored in situ by quartz crystal microbalance with dissipation (qcm-d), and the enzyme binding constants indicated a stronger ...201525929434
megaporous poly(hydroxy ethylmethacrylate) based poly(glycidylmethacrylate-n-methacryloly-(l)-tryptophan) embedded composite cryogel.one-step activation, purification, and stabilization of lipase enzyme were performed by using composite hydrophobic support at low ionic strength with increased surface area during embedding process. a novel hydrophobic poly(hydroxyethylmethacrylate) [phema] based, poly(glycidyl methacrylate-n-methacryloly-(l)-tryptophan) [pgmatrp] bead embedded composite cryogel membrane having specific surface area of 195m(2)/g was used as hydrophobic matrix for adsorption of commercial candida rugosa lipase i ...201525909180
correction: yang, c.-h., et al. immobilization of brassica oleracea chlorophyllase 1 (boclh1) and candida rugosa lipase (crl) in magnetic alginate beads: an enzymatic evaluation in the corresponding proteins. molecules 2014, 19, 11800-11815. 201525905608
enzymatic hydrolysis in an aqueous organic two-phase system using centrifugal partition chromatography.multi-phase reaction systems, mostly aqueous organic systems, are used in enzyme catalysis to convert hydrophobic substrates which are almost insoluble in aqueous media. in this study, a centrifugal partition chromatograph is used as a compact device for enzymatic multi-phase reaction that combines efficient substrate supply to the aqueous phase and separation of both phases in one apparatus. a process design procedure to systematically select the aqueous and organic phase to achieve stable and ...201525773726
a convenient test for lipase activity in aqueous-based solutions.we proposed a convenient and accurate method for the measurement of lipase activity in a uniform aqueous-based substrate solution. in this work, lipase from candida rugosa was used as the model lipase to test its catalytic ability toward p-nitrophenyl palmitate (p-npp), which was suspended in a mixture of p-npp ethanol solution and buffer. an ultraviolet-visible spectrophotometer was used to efficiently measure the liberated p-nitrophenol without extraction or centrifugation. several factors tha ...201525765304
mussel-inspired surface modification of magnetic@graphite nanosheets composite for efficient candida rugosa lipase immobilization.by the facile adhesion way, the novel composite complex by polydopamine (pda) and magnetic graphite nanosheets (fe3o4@gnss) has been successfully synthesized. the resulting composite was characterized by means of scanning electron microscopy, transmission electron microscopy, fourier transform infrared spectra, and raman spectra, x-ray diffraction, x-ray photoelectron spectroscopy, and vibrating sample magnetometry. meanwhile, the pda functionalized fe3o4@gnss (fe3o4@gnss-pda) was applied for ca ...201525752766
facile synthesis of oxidic peg-modified magnetic polydopamine nanospheres for candida rugosa lipase immobilization.a versatile method for the design of polydopamine-coated magnetic material with a brush-like structure used for candida rugosa lipase (crl) immobilization was reported in this work. first, polydopamine (pda) was coated on the surface of fe₃o₄ nanospheres (fe₃o₄ nps) with a controllable thickness via dip coating process, and crl can be immobilized on it directly via covalent bonding. subsequently, pda-functionalized fe₃o₄ nps were modified with dialdehyde polyethylene glycol (peg) to obtain the a ...201525117546
preparation of highly purified pinolenic acid from pine nut oil using a combination of enzymatic esterification and urea complexation.pinolenic acid (pla) is a polyunsaturated fatty acid of plant origin. pla has been successfully enriched according to a two-step process involving lipase-catalysed esterification and urea complexation. for the first step, the fatty acids present in pine nut oil were selectively esterified with lauryl alcohol using candida rugosa lipase. under the optimum conditions of 0.1% enzyme loading, 10% additional water, and 15 °c, pla was enriched up to 43 mol% from an initial value of 13 mol% in the pine ...201525306361
candida rugosa lipase immobilized onto acid-functionalized multi-walled carbon nanotubes for sustainable production of methyl oleate.the chemical production of methyl oleate using chemically synthesized fatty acid alcohols and other toxic chemicals may lead to significant environmental hazards to mankind. being a highly valuable fatty acid replacement raw material in oleochemical industry, the mass production of methyl oleate via environmentally favorable processes is of concern. in this context, an alternative technique utilizing candida rugosa lipase (crl) physically adsorbed on multi-walled carbon nanotubes (mwcnts) has be ...201526267406
harmaline and hispidin from peganum harmala and inonotus hispidus with binding affinity to candida rugosa lipase: in silico and in vitro studies.the inhibitory effect of phenolic compounds and alkaloids of inonotus hispidus and peganum harmala on candida rugosa lipase was investigated, also, their antioxidant activities using dpph, abts and phosphomolybdenum were studied in this paper. the phenolic extracts have shown a stronger antiradical activity than the alkaloids extracts. the enzymatic inhibition produced by these extracts is described here for the first time. the results have shown that the phenolic and the alkaloid extracts are g ...201526151548
molecular identification of uncommon clinical yeast species in iran.by using advanced detection/identification methods, the list of emerging uncommon opportunistic yeast infections is rapidly expanding worldwide. our aim in the present study was sequence-based species delineation of previously unidentified yeasts obtained from a clinically yeast collection.201528680981
the role of microemulsions in lipase-catalyzed hydrolysis reactions.the kinetics of the p-nitrophenyl butyrate hydrolysis reaction, catalyzed by candida rugosa lipase in the water-in-oil microemulsion cetyltrimethylammonium bromide/water/pentanol/hexane, was investigated. the results described in the present manuscript reveal two peculiar characteristics of the reaction: (i) the initial rate of hydrolysis is very fast and (ii) by decreasing the water content of the microemulsion, the reaction rate approaches the typical behavior of reactions performed in aqueous ...201424585724
effects of additives on lipase immobilization in microemulsion-based organogels.an inexpensive, facile, and environmentally benign method was developed to improve the activity and stability of candida rugosa lipase (triacylglycerol acylhydrolase) immobilized on microemulsion-based organogels (crl mbgs) via the addition of additives during immobilization. the additives used were polyethylene glycol (peg) or polysaccharides. this study is the first report on the effect of additives in crl mbgs. among the tested additives, peg produced the most improvement in the immobilized c ...201424497044
preparation of polyphosphazene hydrogels for enzyme immobilization.we report on the synthesis and application of a new hydrogel based on a methacrylate substituted polyphosphazene. through ring-opening polymerization and nucleophilic substitution, poly[bis(methacrylate)phosphazene] (pbmap) was successfully synthesized from hexachlorocyclotriphosphazene. by adding pbmap to methacrylic acid solution and then treating with uv light, we could obtain a cross-linked polyphosphazene network, which showed an ultra-high absorbency for distilled water. lipase from candid ...201425006790
stimuli-sensitive hydrogel based on n-isopropylacrylamide and itaconic acid for entrapment and controlled release of candida rugosa lipase under mild conditions.stimuli responsive ph- and temperature-sensitive hydrogel drug delivery systems, as those based on n-isopropylacrylamide (nipaam) and itaconic acid (ia), have been attracting much of the attention of the scientific community nowadays, especially in the field of drug release. by adjusting comonomer composition, the matrix is enabled to protect the incorporated protein in the highly acidic environment of upper gastrointestinal tract and deliver it in the neutral or slightly basic region of the low ...201424982870
enhanced conjugation of candida rugosa lipase onto multiwalled carbon nanotubes using reverse micelles as attachment medium and application in nonaqueous biocatalysis.three liquid phases (viz. aqueous, nonaqueous, and reverse micelles) were scrutinized as medium for attachment of the enzyme candida rugosa lipase (crl) onto multiwalled carbon nanotubes (cnts). the nanotubes were functionalized to attain carboxyl and amino groups on their surfaces before enzyme conjugation. transmission electron microscopy and fourier transformation infrared spectroscopic studies were used for characterization of the nanotubes during the course of functionalization. high enzyme ...201424828252
improving catalytic hydrolysis reaction efficiency of sol-gel-encapsulated candida rugosa lipase with magnetic β-cyclodextrin nanoparticles.a silica-based β-cyclodextrin was immobilized on magnetic nanoparticles to obtain a macrocyclic compound with magnetic property. then, the β-cyclodextrin-grafted magnetic nanoparticles were encapsulated with candida rugosa lipase in sol-gel matrices using alkoxysilane precursors. the catalytic activity of the encapsulated lipases was evaluated with model reactions, i.e., the hydrolysis of p-nitro-phenylpalmitate (p-npp) and the enantioselective hydrolysis of rasemic naproxen methyl ester that wa ...201424090713
biosynthesis of sucrose-6-acetate catalyzed by surfactant-coated candida rugosa lipase immobilized on sol-gel supports.sucrose-6-acetate is an important intermediate in the preparation of sucralose (a finest sweetener). in our study, candida rugosa lipase coated with surfactant was firstly immobilized on sol-gel supports. then, the immobilized enzyme was used in the regioselective synthesis of sucrose-6-acetate by transesterification of sucrose and vinyl acetate. the screening results revealed that tween 80 was an ideal surfactant to coat lipase immobilized in sol-gel and exhibited the highest yield of sucrose-6 ...201424037039
sensitive impedimetric biosensor for direct detection of diazinon based on lipases.two novel impedimetric biosensors for highly sensitive and rapid quantitative detection of diazinon in aqueous medium were developed using two types of lipase, from candida rugosa (microbial source) (crl) and from porcine pancreas (animal source) (ppl) immobilized on functionalized gold electrode. lipase is characterized to specifically catalyze the hydrolysis of ester functions leading to the transformation of diazinon into diethyl phosphorothioic acid (detp) and 2-isopropyl-4-methyl-6-hydroxyp ...201425072052
enhanced catalysis and enantioselective resolution of racemic naproxen methyl ester by lipase encapsulated within iron oxide nanoparticles coated with calix[8]arene valeric acid complexes.in this study, two types of nanoparticles have been used as additives for the encapsulation of candida rugosa lipase via the sol-gel method. in one case, the nanoparticles were covalently linked with a new synthesized calix[8]arene octa valeric acid derivative (c[8]-c4-cooh) to produce new calix[8]arene-adorned magnetite nanoparticles (np-c[8]-c4-cooh), and then np-c[8]-c4-cooh was used as an additive in the sol-gel encapsulation process. in the other case, iron oxide nanoparticles were directly ...201425012138
study of different reaction schemes for the enzymatic synthesis of polyglycerol polyricinoleate.different strategies for the solvent-free enzymatic production of polyglycerol polyricinoleate (pgpr) were explored in an attempt to simplify and improve the process. besides the conventional procedure (obtaining polyricinoleic acid, followed by its esterification with polyglycerol), two alternative methods are proposed: (1) reversing the synthesis order, i.e. esterification of polyglycerol with ricinoleic acid and then the condensation of ricinoleic acid with the previously obtained polyglycero ...201424403129
removal of zn(ii) from electroplating effluent using yeast biofilm formed on gravels: batch and column studies.present study deals with the removal of zn(ii) ions from effluent using yeast biofilm formed on gravels.201424397917
chemical modification with functionalized ionic liquids: a novel method to improve the enzymatic properties of candida rugosa lipase.chemical modification of lysine residues in candida rugosa lipase (crl) was carried out using five different functional ionic liquids, and about 15.4-25.0 % of the primary amino groups of lysine were modified. enzymatic properties of the native and modified crls were investigated in olive oil hydrolysis reaction. improved thermal stability, catalytic activity in organic solvents, and adaptability to temperature and ph changes were achieved compared with the native enzyme. crl modified by [cholin ...201424488260
highly stabilized lipase in polyaniline nanofibers for surfactant-mediated esterification of ibuprofen.lipase (lp) from candida rugosa was immobilized and stabilized in polyaniline nanofibers (panfs) via a three-step process of enzyme adsorption, precipitation, and cross-linking, which generates the final immobilization called "eapc". the activity of eapc was 5.1 and 5.9 times higher than those of lp immobilizations via enzyme adsorption (ea) and enzyme adsorption/cross-linking (eac), respectively. after incubation in an aqueous buffer under shaking (200 rpm) for 84 days, eapc maintained 74% of i ...201424417226
production of novel "functional oil" rich in diglycerides and phytosterol esters with "one-pot" enzymatic transesterification.diglycerides and phytosterol esters are two important functional lipids. phytosterol esters mixed with dietary diglyceride could not only influence body weight but also prevent or reverse insulin resistance and hyperlipidemia. in this study, a kind of novel "functional oil" rich in both diglycerides and phytosterol esters was prepared with "one-pot" enzymatic transesterification. first, lipase ays (candida rugosa) was immobilized on the porous cross-linked polystyrene resin beads (nka) via hydro ...201424815553
carrier-free immobilization of lipase from candida rugosa with polyethyleneimines by carboxyl-activated cross-linking.carrier-free immobilization of candida rugosa lipase (crl) and polymers containing primary amino groups were cross-linked using carbodiimide. to accomplish this, the free carboxyl groups of the enzyme were activated with carbodiimide-succinimide in organic medium, and then the activated proteins were cross-linked with different polyethylenimines (peis). the effect of the cross-linker chain length, the amount of added bovine serum albumin (bsa), and carbodiimide concentration on the catalytic pro ...201424720524
catalyzed ester synthesis using candida rugosa lipase entrapped by poly(n-isopropylacrylamide-co-itaconic acid) hydrogel.this study reports the synthesis of polymeric matrices based on n-isopropylacrylamide and itaconic acid and its application for immobilization of lipase from candida rugosa. the lipase was immobilized by entrapment method. free and immobilized lipase activities, ph and temperature optima, and storage stability were investigated. the optimum temperature for free and entrapped lipase was found to be 40 and 45 °c, while the optimum ph was observed at ph 7 and 8, respectively. both hydrolytic activi ...201424701136
impact of the configuration of a chiral, activating carrier on the enantioselectivity of entrapped lipase from candida rugosa in cyclohexane.lipase from candida rugosa was loaded into an amphiphilic polymer co-network (apcn) composed of the chiral poly[(r)-n-(1-hydroxybutan-2-yl) acrylamide] [p-(r)-hba] and p-(s)-hba, respectively, linked by poly(dimethylsiloxane). the nanophase-separated amphiphilic morphology affords a 38,000-fold activation of the enzyme in the esterification of 1-phenylethanol with vinyl acetate. further, the enantioselectivity of the entrapped lipase was influenced by the configuration of the chiral, hydrophilic ...201424682791
yarrowia lipolytica lipase lip2: an efficient enzyme for the production of concentrates of docosahexaenoic acid ethyl ester.the production of omega-3 (ω-3) polyunsaturated fatty acids (pufas) rich in cis-4,7,10,13,16,19-docosahexaenoic acid (dha) was studied using lipase-catalysed hydrolysis of a mixture of ethyl esters from tuna oil. lipases from yarrowia lipolytica (yll2), thermomyces lanuginosus (tll) and candida rugosa (crl1, crl3 and crl4) were tested. c. rugosa lipases discriminated esters on the basis of their chain length, with less affinity for γ-linolenate, 11-eicosenoate, arachidonate, epa, dpa and dha eth ...201424657346
lipase immobilized catalytically active membrane for synthesis of lauryl stearate in a pervaporation membrane reactor.a composite catalytically active membrane immobilized with candida rugosa lipase has been prepared by immersion phase inversion technique for enzymatic synthesis of lauryl stearate in a pervaporation membrane reactor. sem images showed that a "sandwich-like" membrane structure with a porous lipase-pva catalytic layer uniformly coated on a polyvinyl alcohol (pva)/polyethersulfone (pes) bilayer was obtained. optimum conditions for lipase immobilization in the catalytic layer were determined. the m ...201425218626
enzymatic interesterification of soybean oil and methyl stearate blends using lipase immobilized on magnetic fe3o4/sba-15 composites as a biocatalyst.the magnetic fe3o4/sba-15 composites were prepared, and treated with 3-aminopropyltriethoxysilane as a carrier material for enzyme immobilization. the immobilization of candida rugosa lipase onto the amino-functionalized fe3o4/sba-15 composite was investigated by using glutaraldehyde as a coupling reagent. the immobilized lipase was then employed as a biocatalyst for the interesterification of soybean oil and methyl stearate in a laboratory-scale operation at 45°c. various techniques, such as fo ...201425213444
calix[n]arene carboxylic acid derivatives as regulators of enzymatic reactions: enhanced enantioselectivity in lipase-catalyzed hydrolysis of (r/s)-naproxen methyl ester.candida rugosa lipase was immobilized with a sol-gel encapsulation procedure in the presence and absence of a calix[n]arene carboxylic acid derivative grafted onto magnetic nanoparticles or in the presence of the calix[n]arene carboxylic acid derivative with fe3o4 magnetic nanoparticles as an additive. through the enantioselective hydrolysis of racemic naproxen methyl ester and the hydrolysis of p-nitrophenylpalmitate, the relative enzyme activity was evaluated and tested. these results show tha ...201424092454
kinetic resolution of profens by enantioselective esterification catalyzed by candida antarctica and candida rugosa lipases.profens (2-arylpropionic acids) are known as one of the major nonsteroidal antiinflammatory drugs (nsaids) used in the treatment of inflammation associated with tissue injury. the inflammatory activity of profens is mainly due to their (s)-enantiomer, whereas they are commercially available not only as pure enantiomers, but as racemates as well. there are several methods widely used in order to obtain enantiomerically pure compounds, however, the kinetic resolution with the application of lipase ...201425080075
immobilization of brassica oleracea chlorophyllase 1 (boclh1) and candida rugosa lipase (crl) in magnetic alginate beads: an enzymatic evaluation in the corresponding proteins.enzymes have a wide variety of applications in diverse biotechnological fields, and the immobilization of enzymes plays a key role in academic research or industrialization due to the stabilization and recyclability it confers. in this study, we immobilized the brassica oleracea chlorophyllase 1 (boclh1) or candida rugosa lipase (crl) in magnetic iron oxide nanoparticles-loaded alginate composite beads. the catalytic activity and specific activity of the boclh1 and crl entrapped in magnetic algi ...201425105918
biocatalytic synthesis of flavor ester "pentyl valerate" using candida rugosa lipase immobilized in microemulsion based organogels: effect of parameters and reusability.pentyl valerate was synthesized biocatalytically using candida rugosa lipase (crl) immobilized in microemulsion based organogels (mbgs). the optimum conditions were found to be ph 7.0, temperature of 37 °c, ratio of concentration of water to surfactant (wo) of 60, and the surfactant sodium bis-2-(ethylhexyl)sulfosuccinate (aot) for mbg preparation. although kinetic studies revealed that the enzyme in free form had high affinity towards substrates (k(m) = 23.2 mm for pentanol and 76.92 mm for val ...201425093166
screening of lipase carriers for reactions in water, biphasic and pure organic solvent systems.in bioprocesses lipases are typically used in immobilized form, irrespective of type of reaction systems, to ensure an even distribution of catalysts in water restricted media and/or to facilitate separation and reuse. in these studies we report on the selection of appropriate enzyme-carrier preparation for hydrolysis reaction in aqueous and biphasic systems and transesterification in organic solvent. for this candida rugosa lipase was bound by adsorption or covalent attachment onto various carr ...201424644546
simultaneous production of fatty acid methyl esters and diglycerides by four recombinant candida rugosa lipase's isozymes.in this study, the catalytic efficiency of four recombinant crl (candida rugosa lipase) isozymes (lip1-lip4) towards the production of fatty acid methyl ester (fame) was compared and evaluated as an alternative green method for industrial applications. the results indicated that the recombinant c. rugosa lip1 enzyme exhibited the highest catalytic efficiency for fame production compared to the recombinant c. rugosa lip2-lip4 enzymes. the optimal conditions were as follows: ph 7.0, methanol/soybe ...201424594166
improvement of the activation of lipase from candida rugosa following physical and chemical immobilization on modified mesoporous silica.lipase from candida rugosa (crl) was chemically and physically immobilized onto four types of rod-shaped mesoporous silica (rsms). rsms prepared using surfactant p123 and poly(ethylene glycol) as co-templates was functionalized with (3-aminopropyl)triethoxysilane (aptes) to obtain p-rsms by post-synthesis grafting. tetraethoxysilane was hydrothermally co-condensed with aptes to obtain c-rsms. a two-step process using aptes and glutaraldehyde was also performed to obtain g-rsms. the effects of mo ...201425491828
photo-controlled deactivation of immobilised lipase.lipase from candida rugosa was immobilised on a quartz surface using an azobenzene-containing, bifunctional linker, which allows deactivation of the immobilised enzyme by irradiation with visible light.201425204471
enhanced biocatalytic esterification with lipase-immobilized chitosan/graphene oxide beads.in this work, lipase from candida rugosa was immobilized onto chitosan/graphene oxide beads. this was to provide an enzyme-immobilizing carrier with excellent enzyme immobilization activity for an enzyme group requiring hydrophilicity on the immobilizing carrier. in addition, this work involved a process for the preparation of an enzymatically active product insoluble in a reaction medium consisting of lauric acid and oleyl alcohol as reactants and hexane as a solvent. this product enabled the s ...201425127038
crystal structures of ophiostoma piceae sterol esterase: structural insights into activation mechanism and product release.sterol esterases are able to efficiently hydrolyze both sterol esters and triglycerides and to carry out synthesis reactions in the presence of organic solvents. their high versatility makes them excellent candidates for biotechnological purposes. sterol esterase from fungus ophiostoma piceae (ope) belongs to the family abh03.01 of the candida rugosa lipase-like proteins. crystal structures of ope were solved in this study for the closed and open conformations. enzyme activation involves a large ...201425108239
oral microbial colonization in children with sickle cell anaemia under long-term prophylaxis with penicillin.sickle cell anaemia (sca) is the most frequent haematological hereditary disease. children with sca are submitted to long-term prophylactic therapy with penicillin, but little is known about its impact on oral microflora. the aim of this study was to evaluate the oral microbial colonization of paediatric patients with sca.201424967510
chiral and isotope analyses for assessing the degradation of organic contaminants in the environment: rayleigh dependence.the rayleigh equation is frequently used to describe isotope fractionation as a function of conversion. in this article we propose to draw a parallel between isotope and enantiomeric enrichments and derive a set of conditions that allow the use of the rayleigh approach to describe the enantiomeric enrichment-conversion dependencies. we demonstrate an implementation of the rayleigh equation for the enantioselective enzymatic hydrolysis of mecoprop-methyl, dichlorprop-methyl, and dimethyl-methylsu ...201424471759
chemical composition profiling and antifungal activity of the essential oil and plant extracts of mesembryanthemum edule (l.) bolus leaves.essential oil from mesembryanthemum edule leaves have been used by the eastern cape traditional healers for the treatment of respiratory tract infections, tuberculosis, dysentery, diabetic mellitus, laryngitis and vaginal infections. the investigation of bioactive compounds in the essential oil of this plant could help to verify the efficacy of the plant in the management or treatment of these illnesses.201425392576
diversity of culturable yeasts in phylloplane of sugarcane in thailand and their capability to produce indole-3-acetic acid.yeasts were isolated by the enrichment technique from the phylloplane of 94 samples of sugarcane leaf collected from seven provinces in thailand. all sugarcane leaf samples contained yeasts and 158 yeast strains were obtained. on the basis of the d1/d2 domain of the large subunit rrna gene sequence analysis, 144 strains were identified to 24 known species in 14 genera belonging to the ascomycota viz. candida akabanensis, candida dendronema, candida mesorugosa, candida michaelii, candida nivarien ...201424442819
candida albicans isolates from a malaysian hospital exhibit more potent phospholipase and haemolysin activities than non-albicans candida isolates.this study was aimed at determining the phospholipase and haemolysin activity of candida isolates in malaysia. a total of 37 candida clinical isolates representing seven species, candida albicans (12), candida tropicalis (8), candida glabrata (4), candida parapsilosis (1), candida krusei (4), candida orthopsilosis (1) and candida rugosa (7) were tested. in vitro phospholipase activity was determined by using egg yolk plate assay whereas in vitro haemolysin activity was tested by using blood plat ...201324522136
determination of yeast diversity in ogi, mawè, gowé and tchoukoutou by using culture-dependent and -independent methods.the maize based ogi and mawè and the sorghum based gowé and tchoukoutou are traditional, spontaneously fermented products widely consumed by the population of benin (west africa). yeast occurrence in the products, as sold on local markets at different locations, was studied using a combination of culture-dependent and independent methods. number of yeasts is varied from 3.75 log10 colony forming units (cfu)/g for ogi to 5.60 log10 cfu/g for tchoukoutou. isolated yeasts (236) were identified base ...201323727651
demonic axe-like conjugated alkynes in combating microbes.a new series of disubstituted alkynes was obtained by microwave induced internal splitting of the corresponding β-oxo-alkylidenetriphenylphosphoranes. the antimicrobial potential of these conjugated alkynes and phosphoranes was assayed in vitro against three gram-positive bacteria (staphylococcus aureus, bacillus subtilis, staphylococcus epidermidis), three gram-negative bacteria (escherichia coli, pseudomonas aeruginosa, klebsiella pneumoniae) and five fungal strains (aspergillus niger, candida ...201323973825
pcr-sscp-based reconstruction of the original fungal flora of heat-processed meat products.food processing of spoiled meat is prohibited by law, since it is a deception and does not comply with food safety aspects. in general, spoilage of meat is mostly caused by bacteria. however, a high contamination level of fungi could be also found in some meat or meat products with certain preserving conditions. in case that unhygienic meat is used to produce heat processed products, the microorganisms will be deactivated by heat, so that they cannot be detected by a standard cultivation method. ...201323361099
production of biodiesel from plant oil hydrolysates using an aspergillus oryzae whole-cell biocatalyst highly expressing candida antarctica lipase b.for enzymatic biodiesel production from plant oil hydrolysates, an aspergillus oryzae whole-cell biocatalyst that expresses candida antarctica lipase b (r-calb) with high esterification activity was developed. each of soybean and palm oils was hydrolyzed using candida rugosa lipase, and the resultant hydrolysates were subjected to esterification where immobilized r-calb was used as a catalyst. in esterification, r-calb afforded a methyl ester content of more than 90% after 6 h with the addition ...201322850174
two-step method of enzymatic synthesis of starch laurate in ionic liquids.enzymatic esterification of starch with long-chain fatty acid was investigated by using ionic liquids 1-butyl-3-methylimidazolium choride ([bmim]cl) and 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][bf4]) as reaction media. an industrial lipase produced by candida rugosa was used to modify starch with lauric acid. the effect of reaction parameters such as the lipase dosage, the molar ratio of lauric acid/anhydroglucose unit (agu) in starch, and the reaction temperature as well as the rea ...201324099559
survey of mycotic mastitis in dairy cows from heilongjiang province, china.a survey of the prevalence rate, pathogenic subspecies, and risk factors of mycotic mastitis in dairy cows from heilongjiang province, china, was conducted. milk samples from 412 cows with chronic mastitis were collected and cultured on 8 % sheep blood agar, macconkey agar, and sabouraud agar with chloramphenicol. counting of the morphologically distinct colonies was performed, as well as the isolation and identification of organisms through phenotypical and physiological criteria. four hundred ...201323813119
preparation of new calix[4]arene-immobilized biopolymers for enhancing catalytic properties of candida rugosa lipase by sol-gel encapsulation.the article describes preparation of new calixarene biopolymers consisting of the immobilization of convenience calixarene derivative onto cellulose and chitosan biopolymers, and the encapsulation of these calixarene biopolymers with candida rugosa lipase within a chemical inert sol-gel supported by polycondensation with tetraethoxysilane and octyltriethoxysilane. the catalytic properties of immobilized lipase were evaluated into model reactions employing the hydrolysis of p-nitrophenylpalmitate ...201323780340
lipases efficiently stearate and cutinases acetylate the surface of arabinoxylan films.this is the first report on successful enzyme catalyzed surface esterification of hemicellulose films. enzyme catalyzed surface acetylation with vinyl acetate and stearation with vinyl stearate were studied on rye arabinoxylan (ax) films. different surface analytical techniques (ft-ir, tof-sims, esca, ca) show that lipases from mucor javanicus, rhizopus oryzae and candida rugosa successfully surface stearate ax films and that a cutinase from fusarium solani pisi surface acetylates these films. t ...201323774036
effect of metal ions on the hydrolytic and transesterification activities of candida rugosa lipase.in order to study the effect of metal ions on lipase activity, hydrolytic and transesterification activities of candida rugosa lipase were investigated in presence of alkali (na⁺ and k⁺), alkaline earth (ca⁺² and ba⁺²) and transition (cr⁺³, fe⁺³, co⁺², cu⁺² and ni⁺²) metal ions. maximum enhancement in hydrolytic activity of lipase was observed by ca⁺², and in transesterification activity by cr⁺³ and co⁺². the kinetics of the lipase catalyzed transesterification (methanolysis and ethanolysis) rea ...201324200940
systematic review and new insights into the molecular characterization of the candida rugosa species complex.recently, candida rugosa was characterized as a species complex comprising four taxa: c. rugosa sensu stricto, candida pseudorugosa, candida neorugosa and candida mesorugosa. although considered relatively rare, several clusters of candidemia due to c. rugosa complex had been reported presenting mortality rates close to 70%. in this work we discuss the systematization, phenotyping and molecular methods based on internal transcribed spacer region (its) sequencing and proteomic analyses for specie ...201324161727
conformation and catalytic properties studies of candida rugosa lip7 via enantioselective esterification of ibuprofen in organic solvents and ionic liquids.enantioselective esterification of ibuprofen was conducted to evaluate the enzyme activity and ees of lipase from candida rugosa (crl7) in ten conventional organic solvents and three ionic liquids. different alcohols were tested for selecting the most suitable acyl acceptor due to the fact that the structure of alcohols (branch and length of carbon chains; location of -oh functional group) could affect the enzyme activity and ees. the results of alcohol and solvent selection revealed that 1-isoo ...201324381516
isolation, identification and growth determination of lactic acid-utilizing yeasts from the ruminal fluid of dairy cattle.ruminal organic acid production, especially lactic acid, can be modified by feeding cattle highly concentrated diets, which have been shown to adversely affect dairy cattle health. therefore, the use of lactic acid-utilizing organisms is considered to be a potential method for controlling lactic acid levels. this study was conducted to isolate and identify lactic acid-utilizing yeasts from the ruminal fluid of dairy cattle and to determine the specific growth rate and generation time when using ...201323565722
a magnetically separable biocatalyst for resolution of racemic naproxen methyl ester.candida rugosa lipase (crl) was encapsulated via the sol-gel method, using 5, 11, 17, 23-tetra-tert-butyl-25,27-bis(2-aminopyridine)carbonylmethoxy-26, 28-dihydroxy-calix[4]arene-grafted magnetic fe3o4 nanoparticles (calix-m-e). the catalytic activity of encapsulated lipase (calix-m-e) was tested both in the hydrolysis of p-nitrophenyl palmitate (p-npp) and the enantioselective hydrolysis of racemic naproxen methyl ester. the present study demonstrated that the calixarene-based compound has the ...201323525833
assessment of activities and conformation of lipases treated with sub- and supercritical carbon dioxide.in order to illustrate the underlining mechanism of the effect of high pressure on lipases from different resources, the influence of compressed carbon dioxide treatment on the esterification activities and conformation of the three lipases candida rugosa lipase (crl), pseudomonas fluorescens lipase, and rhizopus oryzae lipase was investigated in the present work. the results showed that the lipases activities were significantly enhanced in most of high-pressure treatments, except the pressure h ...201323417391
fungal genomes mining to discover novel sterol esterases and lipases as catalysts.sterol esterases and lipases are enzymes able to efficiently catalyze synthesis and hydrolysis reactions of both sterol esters and triglycerides and due to their versatility could be widely used in different industrial applications. lipases with this ability have been reported in the yeast candida rugosa that secretes several extracellular enzymes with a high level of sequence identity, although different substrate specificity. this versatility has also been found in the sterol esterases from th ...201324138290
synthesis of phytosteryl ester containing pinolenic acid in a solvent-free system using immobilized candida rugosa lipase.phytosteryl ester synthesized with pinolenic acid (pla) from pine nut oil is expected to have features of both phytosterol and pla. in this study, lipase from candida rugosa (crl) was immobilized and then used to optimize conditions for synthesis of phytosteryl ester containing pla. lewatit vp oc 1600, a macroporous hydrophobic resin, was selected as the best carrier, and the optimum condition for the immobilization of crl was established. with immobilized crl prepared, synthesis of phytosteryl ...201323988007
immobilization of candida rugosa lipase on superparamagnetic fe3o4 nanoparticles for biocatalysis in low-water media.a simple immobilization method for candida rugosa lipase on superparamagnetic fe3o4 nanoparticles is described. the fe3o4 nanoparticles were coated with pei and candida rugosa lipase was adsorbed on these particles via electrostatic interactions. the immobilization resulted in marginal simultaneous purification. however, the immobilized preparation showed 110× higher transesterification activity in low-water media. it was also efficient in kinetic resolution of (±)-1-phenylethanol with eep of 99 ...201323934801
one-pot solvothermal synthesis of highly water-dispersible size-tunable functionalized magnetite nanocrystal clusters for lipase immobilization.a facile one-pot synthesis of highly water-dispersible size-tunable magnetite (fe3o4) nanocrystal clusters (mncs) end-functionalized with amino or carboxyl groups by a modified solvothermal reduction reaction has been developed. dopamine and 3,4-dihydroxyhydroxycinnamic acid were used for the first time as both a surfactant and interparticle linker in a polylol process for economical and environment-friendly purposes. morphology, chemical composition, and magnetic properties of the prepared part ...201323616374
preparation and characterization of gelatin hydrogel support for immobilization of candida rugosa lipase.a series of gelatin hydrogels were prepared by crosslinking method using glutaraldehyde (ga). the hydrogels were characterized by gel formation, swelling/degradation tests, and ftir analysis. the variations of swelling percentages (s%) with time, temperature, and ph were determined. it is found that the increasing amount of ga causes the decreasing in s% values from 366 to 213% and g-1 was found to be the most swollen hydrogel at ph 7.4 and 37 °c. degradation tests of hydrogel samples were carri ...201322812721
lipase immobilization on hyper-cross-linked polymer-coated silica for biocatalytic synthesis of phytosterol esters with controllable fatty acid composition.in this study, a novel mixed-mode composite material, sio(2)@p(maa-co-vbc-co-dvb), was prepared via the hyper-cross-linking of its precursor, which was produced via suspension polymerization in the presence of sio(2) particles. candida rugosa lipase (crl) was immobilized on the sio(2)@p(maa-co-vbc-co-dvb) particles via hydrophobic and weak cation-exchange interaction. the resulting immobilized crl showed much better thermal stability and reusability in comparison to free crl. on the basis of the ...201323199227
magnetically modified spent grain as a low-cost, biocompatible and smart carrier for enzyme immobilisation.food and feed technology and biotechnology benefit from the use of immobilised enzymes. new low-cost enzyme carriers exhibiting high biocompatibility and response to external magnetic field can substantially improve the application potential of immobilised enzyme systems.201323108838
covalent immobilization of candida rugosa lipase on aldehyde functionalized hydrophobic support and the application for synthesis of oleic acid ester.this study focuses on candida rugosa lipase (crl) immobilization by covalent attachment on poly(ethylene terephthalate)-grafted glycidyl methacrylate (pet-g-gma) fiber. the immobilization yielded a protein loading of 2.38 mg g(-1) of pet-g-gma fiber. the performances of the immobilized and free crls were evaluated with regard to hydrolysis of olive oil and esterification of oleic acid. the optimum activity ph of the crl was changed by immobilization to neutral range. the maximum activity of the ...201323574345
structural and dynamic features of candida rugosa lipase 1 in water, octane, toluene, and ionic liquids bmim-pf6 and bmim-no3.ionic liquids (ils) and organic chemicals can be used as solvents in biochemical reactions to influence the structural and dynamic features of the enzyme, sometimes detrimentally. in this work we report the results for molecular dynamics simulations of candida rugosa lipase (crl) in ils bmim-pf6 and bmim-no3, as well as organic solvents toluene and octane in an effort to explore the role of solvent on the structure and dynamics of an enzyme known to be active in many nonaqueous media. simulation ...201323387335
extracellular enzyme production and phylogenetic distribution of yeasts in wastewater treatment systems.the abilities of yeasts to produce different extracellular enzymes and their distribution characteristics were studied in municipal, inosine fermentation, papermaking, antibiotic fermentation, and printing and dyeing wastewater treatment systems. the results indicated that of the 257 yeasts, 16, 14, 55, and 11 produced lipase, protease, manganese dependant peroxidase (mnp), and lignin peroxidase (lip), respectively. they were distributed in 12 identified and four unidentified genera, in which ca ...201323261999
the derivation of a chiral substituent code for secondary alcohols and its application to the prediction of enantioselectivity.a chiral substituent code was proposed based on the features of secondary alcohols, in which a chiral center is attached to two substituents in addition to oh and h substituents. the new chirality code, which was generated by predefining positional information of four substituents attached to stereocenter, was applied to two datasets composed of secondary alcohols as the enantioselective products of asymmetric reactions. in the first dataset, the chemical reaction was catalyzed by a biocatalyst, ...201323666031
synthesis, enantiomer separation, and absolute configuration of 2,6-oxygenated 9-azabicyclo[3.3.1]nonanes.the synthesis of the enantiomerically pure n-boc 9-azabicyclo[3.3.1]nonane-2,6-dione (4b), a potentially useful chiral building block, from n-bn and n-boc 9-azabicyclo[3.3.1]nonane-2,6-diols 2a and 2b was accomplished. the enantiomer resolution of diols 2a and 2b was achieved by crystallization of their diastereomeric esters or by kinetic resolution of the racemic diol 2a using lipase from candida rugosa (crl). both enantiomers of n-boc protected diol 2b were converted into the corresponding ena ...201323635000
candida mesorugosa sp. nov., a novel yeast species similar to candida rugosa, isolated from a tertiary hospital in brazil.candida rugosa is a yeast species that is emerging as a causative agent of invasive infection, particularly in latin america. recently, c. pseudorugosa was proposed as a new species closely related to c. rugosa. we evaluated in this investigation the genetic heterogeneity within the c. rugosa species complex. all clinical isolates used in this study were identified phenotypically as c. rugosa but were genotypically different from the c. rugosa type, atcc 10571. rapd marker analysis revealed less ...201322928924
lipase catalyzed ultrasonic synthesis of poly-4-hydroxybutyrate-co-6-hydroxyhexanoate.four different lipases were compared for ultrasound-mediated synthesis of the biodegradable copolymer poly-4-hydroxybutyrate-co-6-hydroxyhexanoate. the copolymerization was carried out in chloroform. of the enzymes tested, novozym 435 exhibited the highest copolymerization rate, in fact the reaction rate was observed to increase with about 26-fold from 30 to 50°c (7.9×10(-3)ms(-1)), sonic power intensity of 2.6×10(3)wm(-2) and dissipated energy of 130.4jml(-1). copolymerization rates with the ca ...201323231942
comparison of artificial neural network (ann) and response surface methodology (rsm) in optimization of the immobilization conditions for lipase from candida rugosa on amberjet(®) 4200-cl.candida rugosa lipase (crl) is an important industrial enzyme that is successfully utilized in a variety of hydrolysis and esterification reactions. this work describes the optimization of immobilization conditions (enzyme/support ratio, immobilization temperature, and buffer concentration) of crl on the anionic resin amberjet® 4200-cl, using enantioselectivity (e) as the reference parameter. the model reaction used for this purpose is the acylation of (r,s)-1-phenylethanol. optimal conditions f ...201323215653
enzyme catalysis in organic solvents: influence of water content, solvent composition and temperature on candida rugosa lipase catalyzed transesterification.in the present study the influence of water content, solvent composition and reaction temperature on the transesterification of 1-phenylpropan-2-ol catalyzed by candida rugosa lipase was examined. reactions were carried out in different mixtures of hexane and tetrahydrofurane. the studies showed that an increasing water content of the organic solvent results in an increasing enzyme activity and a decreasing enantiomeric excess. furthermore, a significant influence of the solvent hydrophilicity b ...201222465292
first case report of bloodstream infection due to a candida species closely related to the novel species candida pseudorugosa.candida pseudorugosa is a novel species closely related to candida rugosa for which only one case has been reported. we report the first case of a bloodstream infection in humans caused by a candida sp. closely related to c. pseudorugosa. we contribute evidence to show this organism as a potential human pathogen that may be misidentified by conventional methods, also pointing out its lower sensitivity to azoles and other antifungal agents.201222461681
lipase immobilization on differently functionalized vinyl-based amphiphilic polymers: influence of phase segregation on the enzyme hydrolytic activity.microbial lipase from candida rugosa was immobilized by physical adsorption onto an ethylene-vinyl alcohol polymer (eval) functionalized with acyl chlorides. to evaluate the influence of the reagent chain-length on the amount and activity of immobilized lipase, three differently long aliphatic fatty acids were employed (c8, c12, c18), obtaining eval functionalization degrees ranging from 5% to 65%. the enzyme-polymer affinity increased with both the length of the alkyl chain and the matrix hydro ...201222295868
high performance liquid chromatography determination of fatty acids in drying oils following lipase action.this paper describes a quantitative analytical procedure to determine the fatty acid composition in drying oils like linseed, walnut and poppy seed. the procedure required the enzymatic hydrolysis of the oil triacylglycerol families by the action of candida rugosa lipase. the fatty acids (ffas) produced (linolenic, myristic, linoleic, palmitic, oleic and stearic) were extracted with n-heptane and derivatized with α-bromoacetophenone. their separation and quantitative determination were performed ...201222368115
lipase incorporated ionic liquid polymers as active, stable and reusable biocatalysts.the aim of this study was to develop ionic liquid (il) polymer materials incorporating enzymes that can be used as active, stable and reusable biocatalysts. to this goal, candida rugosa lipase has been microencapsulated in surfactant aggregates formed in an il monomer or the solution of an il monomer/il and then incorporated into polymer frameworks through the free radical polymerization of an il (1-vinyl-3-ethylimidazolium bis(trifluoromethyl-sulfonyl) amide) ([veim][tf(2)n]). the activity, sta ...201222903458
immobilization of lipases on alkyl silane modified magnetic nanoparticles: effect of alkyl chain length on enzyme activity.biocatalytic processes often require a full recycling of biocatalysts to optimize economic benefits and minimize waste disposal. immobilization of biocatalysts onto particulate carriers has been widely explored as an option to meet these requirements. however, surface properties often affect the amount of biocatalysts immobilized, their bioactivity and stability, hampering their wide applications. the aim of this work is to explore how immobilization of lipases onto magnetite nanoparticles affec ...201222952688
isoamylacetate production by entrapped and covalently bound candida rugosa and porcine pancreatic lipases.candida rugosa lipase (crl) and porcine pancreatic lipase (ppl) were immobilised by entrapping and also by covalent binding for use in synthesis of isoamyl acetate (iaac), which has a typical banana flavour. lipase entrapment was carried out by dripping sodium alginate (na-alg)-chitosan (chi)-lipase mixture into cacl(2)-glutaraldehyde (gal) solution to obtain ca-alg/chi(crl/ppl). immobilisation conditions were optimised as 1.5% na-alg, 1.5% chitosan and 0.15% gal. ca-alg/chi(crl/ppl) samples sho ...201222980809
immobilization of candida rugosa lipase on mcm-41 for the transesterification of cotton seed oil.present study demonstrated the preparation of mcm-41 as a support for the immobilization of candida rugosa lipase by the physical adsorption technique. the lipase immobilized mcm-41 has been characterized by scanning electron microscopic and ftir techniques. at ph 6, maximum lipase immobilization (250 mg/g) on mcm support has been observed and the immobilized lipase was employed as biocatalyst for the transesterification of the cotton seed oil with methanol. the ph of the reaction medium, reacti ...201222975780
evaluation of structure and hydrolysis activity of candida rugosa lip7 in presence of sub-/super-critical co₂.this work aimed to assess the effect of sub-/super-critical co₂ on the structure and activity of candida rugosa lip7 (crl7) in its solution form. the structure was examined by sds-page gel electrophoresis, circular dichroism (cd) and fluorescence spectra photometry. results revealed that the primary structure remained intact after sub-/super-critical co₂ treatment, and the secondary structure altered at the pressure of 10 mpa and temperature 40°c for 30 min incubation, but it was reflex to its n ...201223040391
effect of poly(vinyl acetate-acrylamide) microspheres properties and steric hindrance on the immobilization of candida rugosa lipase.poly(vinyl acetate-acrylamide) microspheres were synthesized in the absence or presence of isooctane via suspension polymerization and utilized as carriers to immobilize candida rugosa lipase. when the hydrophobic/hydrophilic surface characteristics of the microspheres were modified by changing the ratio of vinyl acetate (hydrophobic monomer) to acrylamide (hydrophilic monomer) from 50:50 to 86:24, the immobilization ratio changed from 45% to 92% and the activity of the immobilized lipase increa ...201222989650
preparation of superparamagnetic fe3o4@alginate/chitosan nanospheres for candida rugosa lipase immobilization and utilization of layer-by-layer assembly to enhance the stability of immobilized lipase.superparamagnetic alginate nanospheres with diameter of 50 nm were prepared by self-assembly of alginate in the ca(2+) solution; and then superparamagnetic alginate/chitosan nanospheres, which have positive charge and could adsorb lipase directly, were obtained with a following assembly of chitosan based on the electrostatic interaction between alginate and chitosan. subsequently, oxidic poly (ethylene glycol) was used to functionalize the magnetic alginate/chitosan nanospheres. thus, the magnet ...201222985256
controlled release of lipase from candida rugosa loaded into hydrogels of n-isopropylacrylamide and itaconic acid.the series of poly(n-isopropylacrylamide-co-itaconic acid) hydrogels, with lipase from candida rugosa as a model protein, were synthesized by free radical copolymerization. the composition of hydrogels was varied by monomers ratio, crosslinking agent concentration and amounts of lipase, which was loaded by in situ polymerization. all samples were characterized regarding morphology. the investigation of hydrogel swelling properties revealed their ph and temperature sensitive character. protein lo ...201222759642
heterologous expression systems for lipases: a review.the production of heterologous lipases is one of the most promising strategies to increase the productivity of the bioprocesses and to reduce costs, with the final objective that more industrial lipase applications could be implemented. in this chapter, an overview of the most common microbial expression systems for the overproduction of microbial lipases is presented. prokaryotic system as escherichia coli and eukaryotic systems as saccharomyces cerevisiae and pichia pastoris are analyzed and c ...201222426719
enhancement of the activity and enantioselectivity of lipase by sol-gel encapsulation immobilization onto β-cyclodextrin-based polymer.candida rugosa lipase was encapsulated within a chemically inert sol-gel support prepared by polycondensation with tetraethoxysilane and octyltriethoxysilane in the presence of β-cyclodextrin-based polymer. the catalytic activity of the encapsulated lipases was evaluated both in the hydrolysis of p-nitrophenylpalmitate and the enantioselective hydrolysis of racemic naproxen methyl ester. it has been observed that the percent activity yield of the encapsulated lipase was 65 u/g, which is 7.5 time ...201222383051
preparation of coaxial-electrospun poly[bis(p-methylphenoxy)]phosphazene nanofiber membrane for enzyme immobilization.a core/sheath nanofiber membrane with poly[bis(p-methylphenoxy)]phospha-zene (pmpph) as the sheath and easily spinnable polyacrylonitrile (pan) as the core was prepared via a coaxial electrospinning process. field-emission scanning electron microscopy and transmission electron microscopy were used to characterize the morphology of the nanofiber membrane. it was found that the concentration of the pan spinning solution and the ratio of the core/sheath solution flow rates played a decisive role in ...201223203055
resonance energy transfer between protein and rhamnolipid capped zns quantum dots: application in in-gel staining of proteins.the interaction of proteins with quantum dots is an interesting field of research. these interactions occur at the nanoscale. we have probed the interaction of bovine serum albumin (bsa) and candida rugosa lipase (crl) with rhamnolipid capped zns (rhlznsqds) using absorption and fluorescence spectroscopy. optical studies on mixtures of rhlznsqds and proteins resulted in förster's resonance energy transfer (fret) from proteins to qds. this phenomenon has been exploited to detect proteins in agaro ...201222580141
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