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scale-up fermentation of recombinant candida rugosa lipase expressed in pichia pastoris using the gap promoter.the high-cell-density fermentation of candida rugosa lipase in the constitutive pichia pastoris expression system was scaled up from 5 to 800 l in series by optimizing the fermentation conditions at both lab scale and pilot scale. the exponential feeding combined with ph-stat strategy succeeded in small scale studies, while a two-stage fermentation strategy, which shifted at 48 h by fine tuning the culture temperature and ph, was assessed effective in pilot-scale fermentation. the two-stage stra ...200818087738
covalent immobilization of lipase from candida rugosa onto poly(acrylonitrile-co-2-hydroxyethyl methacrylate) electrospun fibrous membranes for potential bioreactor application.a simple way of fabricating enzymatic membrane reactor with high enzyme loading and activity retention from the conjugation between nanofibrous membrane and lipase was devised. poly(acrylonitrile-co-2-hydroxyethyl methacrylate) (panchema) was electrospun into fibrous membrane and used as support for enzyme immobilization. the hydroxyl groups on the fibrous membrane surface were activated with epichlorohydrin, cyanuric chloride or p-benzoquinone, respectively. lipase from candida rugosa was coval ...200818248984
candida rugosa lipase-catalysed kinetic resolution of 2-substituted-aryloxyacetic esters with dimethylsulfoxide and isopropanol as additives.candida rugosa lipase-catalysed hydrolysis of three different 2-substituted-aryloxyacetic esters was performed in aqueous buffer containing dimethyl sulphoxide and isopropanol from 0 to 80% v/v as additives, in order to obtain an enhancement of the enantioselectivity. for 2-(p-chlorophenoxy)acetic acid and 2-n-butyl-2-(p-chlorophenoxy)acetic acid ethyl esters, dmso enhanced enzyme enantioselectivity more than ipa with an opposite enzymatic enantiopreference. the cosolvents moderately improved ca ...200818074337
lipase specificity towards eicosapentaenoic acid and docosahexaenoic acid depends on substrate structure.the fatty acid specificity of five lipases towards eicosapentaenoic acid (epa) and docosahexaenoic acid (dha) was evaluated in the hydrolysis of fish oil, squid oil and a model system. the model system contained methyl esters of epa, dha and palmitic acid. all the investigated lipases discriminated against both epa and dha more in the model system than in the natural oils. thus both epa and dha were more easily hydrolysed from a glyceride than from a methyl ester. in the model system, the lipase ...200818067872
blue native electrophoresis study on lipases.we have developed a modified blue native polyacrylamide gel electrophoresis (page) protocol that can overcome aggregation of lipases seen in native page. we have shown that two lipases, pseudomonas aeruginosa lipase and candida rugosa lipase, which aggregate in the native gel, can be resolved using our protocol. activity staining was done to test for the functionality of the two lipases.200818381198
production of n-3 polyunsaturated fatty acid concentrate from sardine oil by immobilized candida rugosa lipase.this study was conducted to develop an immobilized-enzyme system to entrap lipase in chitosan-alginate-cacl(2) beads for the purpose of concentrating n-3 polyunsaturated fatty acids (n-3 pufas) from sardine oil. lipase was immobilized by an ionotropic gelatin method analyzed for characteristics. optimum ph of immobilized lipase shifted from ph 7.0 to 6.0 and immobilized lipase showed higher stability against ph and temperature changes. original sardine oil contained 38.1% n-3 pufas (25.2% 20:5n3 ...200818387091
monoglycerides and diglycerides synthesis in a solvent-free system by lipase-catalyzed glycerolysis.five lipases were screened (thermomyces lanuginosus free and immobilized forms, candida antarctica b, candida rugosa, aspergillus niger, and rhizomucor miehei) to study their ability to produce monoglycerides (mg) and diglycerides (dg) through enzymatic glycerolysis of soybean oil. lipase from c. antarctica was further studied to verify the enzyme load (wt% of oil mass), the molar ratio glycerol/oil, and the water content (wt% of glycerol) on the glycerolysis reaction. the best dg and mg product ...200818421596
conversion of sunflower oil to biodiesel by alcoholysis using immobilized lipase.transesterification reaction was performed using sunflower oil and short-chain alcohol by immobilized lipases in organic solvents. the fatty acid ester, which is the product of this reaction, can be used as a diesel fuel that does not produce sulfur oxide and minimize the soot particulate. immobilized porcine pancreatic lipase (ppl) and candida rugosa lipase (crl) showed the satisfactory activity in these reactions. immobilization of lipases was carried out using inorganic absorbance celit 545 p ...200818437590
a chemoenzymatic approach to the synthesis of enantiomerically pure (s)-3-hydroxy-gamma-butyrolactone.optically pure (s)-3-hydroxy-gamma-butyrolactone, an important chiral building block in the pharmaceutical industry, was synthesized from l: -malic acid by combining a selective hydrogenation and a lipase-catalyzed hydrolysis. lipase from candida rugosa was found to be the most efficient enzyme for the hydrolysis of (s)-beta-benzoyloxy-gamma-butyrolactone. the use of organic solvent-aqueous two-phase system was employed to extract benzoic acid generated from enzymatic hydrolysis of the substrate ...200818446525
reusability of surfactant-coated candida rugosa lipase immobilized in gelatin microemulsion-based organogels for ethyl isovalerate synthesis.in our previous study, a surfactant-coated candida rugosa lipase immobilized in microemulsion-based organogels was exploited for the synthesis of ethyl isovalerate. in the present study, we are focusing on the effective reuse of lipase immobilized in microemulsion-based organogels (mbgs) in terms of retainment of the catalytic activity. as water is one of the co-products in esterification reactions, the removal of water becomes a priority to allow the reaction to work in the forward direction an ...200818467869
immobilization of lipase by ultrafiltration and cross-linking onto the polysulfone membrane surface.in this study, a biphasic enzymatic membrane reactor was made by immobilizing candida rugosa lipase onto the dense surface of polysulfone ultrafiltration membrane by filtration and then cross-linking with glutaraldehyde solution. the reactor was further applied for the hydrolysis of olive oil, the performance of which was evaluated in respect of apparent reaction rate based on the amount of fatty acids extracted into the aqueous phase per minute and per membrane surface. it was found that the ul ...200817591438
immobilization of candida rugosa lipase on poly(allyl glycidyl ether-co-ethylene glycol dimethacrylate) macroporous polymer particles.macroporous polymer particles containing surface epoxy groups were synthesized for immobilization of candida rugosa lipase (crl). the effect of incorporation of two different sets of monomers [allyl glycidyl ether (age) and glycidyl methacrylate (gma)] and the effect of crosslinking density on immobilization of lipase were studied. age-co-egdm polymers gave higher binding and expression of lipase than gma-co-egdm polymers. optimization of immobilization parameters was done with respect to immobi ...200817766105
covalent attachment of candida rugosa lipase on chemically modified hybrid matrix of polysiloxane-polyvinyl alcohol with different activating compounds.candida rugosa lipase was immobilized by covalent binding on hybrid matrix of polysiloxane-polyvinyl alcohol chemically modified with different activating agents as glutaraldehyde, sodium metaperiodate and carbonyldiimidazole. the experimental results suggested that functional activating agents render different interactions between enzyme and support, producing consequently alterations in the optimal reaction conditions. properties of the immobilized systems were assessed and their performance o ...200817889514
studies of optimum conditions for covalent immobilization of candida rugosa lipase on poly(gamma-glutamic acid) by rsm.poly(gamma-glutamic acid) (gamma-pga) is a material of polymer. immobilization of candida rugosa lipase (lipase ay-30) by covalent binding on gamma-pga led to a markedly improved performance of the enzyme. response surface methodology (rsm) and 3-level-3-factor fractional factorial design were employed to evaluate the effects of immobilization parameters, such as immobilization time (2-6h), immobilization temperature (0-26 degrees c), and enzyme/support ratio (0.1-0.5, w/w). based on the analysi ...200817706421
high-yield synthesis of wax esters catalysed by modified candida rugosa lipase.candida rugosa lipase (crl) was applied in a non-solvent esterification reaction to yield twelve wax esters. all products were obtained in nearly 100% yield for 10 h at 50 degrees c when immobilized peg(2000)-activated c. rugosa lipase was added to the reaction mixture. the surfactant had also a beneficial effect on the stability of the biocatalytic preparation with 83% of its activity conserved after the seventh run of repeated batch reactions.200817957342
promoter analysis and differential expression of the candida rugosa lipase gene family in response to culture conditions.five lipase genes have been identified and sequenced from candida rugosa. however, as the sequences of lip multigene family are extremely closely related, it is difficult to characterize the expression spectrum of lip genes. in the present work we have cloned, sequenced, and analyzed the promoters of these five lip isoform genes, and several putative transcriptional elements including oleate response element (ore) and upstream activation sequence 1 (uas1) were identified. a quantitative real-tim ...200818290622
ph memory of immobilized lipase for (+/-)-menthol resolution in ionic liquid.magnetic deae-gma-edma microspheres were prepared via suspension polymerization and used for the immobilization of candida rugosa lipase by ion exchange. the effect of ph values on the immobilization of lipase was investigated. resolution of (+/-)-menthol in the hydrophobic ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was performed by immobilized lipase-catalyzed enantioselective esterification with propionic anhydride as acyl donor. the effects of ph condition at lipase immobili ...200818338863
stable colloidal dispersions of a lipase-perfluoropolyether complex in liquid and supercritical carbon dioxide.the technique of hydrophobic ion pairing was used to solubilize the lipase from candida rugosa in a fluorinated solvent, perfluoromethylcyclohexane (pfmc), in complex with a perfluoropolyether (pfpe) surfactant, kdp 4606. the enzyme-surfactant complex was determined to have a hydrodynamic diameter of 6.5 nm at atmospheric pressure by dynamic light scattering (dls), indicating that a single lipase molecule is stabilized by surrounding surfactant molecules. the complex formed a highly stable collo ...200818363394
[inhibition of lipase activity by low-molecular-weight chitosan].inhibition of enzymatic activity of lipase (ec 3.1.1.3) from the fungus candida rugosa and wheat (triticum aestivum l.) germ by low-molecular-weight chitosan with an average molecular weight of 5.7 kda in reactions of p-nitrophenyl palmitate cleavage was studied. preincubation of lipases with chitosan, prior to addition of the substrate to solution, showed that equilibrium during the lipase-inhibitor complex formation was reached within 30 min. the inhibition constants for c. rugosa lipase and w ...200818491595
esterification and hydrolytic activities of candida rugosa lipase isoform 1 (lip1) immobilized on celite 545, duolite a7, and sephadex g-25.the esterification and hydrolytic activities of free and immobilized candida rugosa lipase isoform 1 (lip1) were investigated. esterification activity was determined by reacting caprylic acid with glycerol in the presence of molecular sieves (30%, w/w), and the volume of 1.0 m naoh consumed by the reaction products upon titration was used to calculate esterification activity. caprylic acid was also reacted with cottonseed oil, and the amount of caprylic acid incorporated after 12 h of reaction w ...200818850711
optimization of the process for biodiesel production using a mixture of immobilized rhizopus oryzae and candida rugosa lipases.in this study, the enzymatic process for biodiesel production was optimized using a mixture of immobilized rhizopus oryzae and candida rugosa lipases. the optimal temperature and agitation speed for biodiesel production were 45oc and 300 rpm, respectively. the optimal ratio of r. oryzae and c. rugosa lipases in the mixture was 3:1 (w:w). when 3mmol of methanol was the initial reaction medium and 3mmol of methanol was added every 1.5 h during biodiesel production, biodiesel conversion was over 98 ...200819131695
evaluation of medium components by plackett-burman statistical design for lipase production by candida rugosa and kinetic modeling.lipase production by candida rugosa was carried out in submerged fermentation. plackett-burman statistical experimental design was applied to evaluate the fermentation medium components. the effect of twelve medium components was studied in sixteen experimental trials. glucose, olive oil, peptone and fecl3.6h2o were found to have more significance on lipase production by candida rugosa. maximum lipase activity of 3.8 u ml(-1) was obtained at 50 h of fermentation period. the fermentation was carr ...200818589820
immobilization of lipases on hydrophobilized zirconia nanoparticles: highly enantioselective and reusable biocatalysts.our study has demonstrated for the first time that zirconia nanoparticles modified by a simple carboxylic surfactant of a very long alkyl chain can significantly enhance the activity of the immobilized lipases for asymmetric synthesis in organic media. zirconia nanoparticles of ca. 20 nm diameter were grafted with carboxylic surfactant modifiers from tween 85 and erucic acid. the surface of nanoparticles was successfully changed from hydrophilic to hydrophobic. lipases from candida rugosa and ps ...200818656972
microbial spoilage of date rutab collected from the markets of al-hofuf city in the kingdom of saudi arabia.microbial spoilage was monitored in 520 samples of dates in the rutab stage purchased from retail outlets in al-hofuf city, saudi arabia, and incubated in the laboratory under different conditions. no spoilage was observed in 130 samples incubated in open containers at 5 or 30 degrees c for up to 60 days. spoilage occurred in 42 of 130 samples incubated in covered containers at 5 degrees c after about 80 days and was caused mainly by penicillium spp. and cladosporium spp. mixed populations of la ...200818680940
langmuir-blodgett based lipase nanofilms of unique structure-function relationship.proteins represent versatile building blocks for realization of nanostructured materials of unique structure-function relationship to be applied in nanobiotechnology. following a recent work [bruzzese, d., pastorino, l., pechkova, e., sivozhelezov, nicolini, c., increase of catalytic activity of lipase towards olive oil by langmuir-film immobilization of lipase, enzyme and microbial technology, submitted for publication.], the langmuir-blodgett technique was utilized to develop nanostructured cr ...200818721850
evaluation of new colorimetric vitek 2 yeast identification card by use of different source media.the new colorimetric vitek 2 yst card was evaluated for identification of yeasts (136 strains) with respect to the influence of different source media. the vitek 2 yst card achieved satisfactory results for all yeast species tested, with the exception of candida guilliermondii, candida norvegensis, candida parapsilosis, candida rugosa, and candida tropicalis. after simple additional tests, 93.7% of all the strains tested were correctly identified. a significant influence of the isolation medium ...200818799700
antimicrobial effects of turkish propolis, pollen, and laurel on spoilage and pathogenic food-related microorganisms.the antimicrobial activities of propolis extract, pollen extract, and essential oil of laurel (laurus nobilis l.) at concentrations from 0.02% to 2.5% (vol/vol) were investigated on bacteria (bacillus cereus, bacillus subtilis, escherichia coli, salmonella typhimurium, staphylococcus aureus, yersinia enterocolitica, enterococcus faecalis, and listeria monocytogenes), yeasts (saccharomyces cerevisiae and candida rugosa), and molds (aspergillus niger and rhizopus oryzae). pollen has no antimicrobi ...200818800911
[in vitro amphotericin b susceptibility of korean bloodstream yeast isolates assessed by the clsi broth microdilution method, etest, and minimum fungicidal concentration test].although amphotericin b (amb) has a wide spectrum of activity that encompasses the majority of yeast isolates, there have been recent reports suggesting that some yeast isolates exhibit decreased susceptibility to amb. however, in vitro amb susceptibility of yeast species isolates from blood cultures in korea has not been fully surveyed.200818971615
stepwise esterification of phytosterols with conjugated linoleic acid catalyzed by candida rugosa lipase in solvent-free medium.we conducted a near quantitative esterification of phytosterols from soybean oil deodorizer distillate with conjugated linoleic acid. we used a 1:1 molar ratio of sterols to conjugated linoleic acid. for that matter, stepwise addition of sterols was investigated. total sterols were divided into several portions and added sequentially to the reaction mixture. using this methodology, purities of up to 80% steryl esters were obtained that consumed more than 90% of the total conjugated linoleic acid ...200819134551
preparation of nucleoside-carbohydrate phosphodiester prodrug analogues by chemoenzymatic procedure.an efficient synthesis protocol for the glucosyl-nucleoside phosphodiester derivatives has been developed. these mononucleotides were designed to act as pronucleotides with potential to deliver the parent compound as its monophosphate. key step of the synthesis is the regioselective hydrolysis of peracetylated alpha-d-glucose catalyzed by candida rugosa lipase.200818776273
understanding structural features of microbial lipases--an overview.the structural elucidations of microbial lipases have been of prime interest since the 1980s. knowledge of structural features plays an important role in designing and engineering lipases for specific purposes. significant structural data have been presented for few microbial lipases, while, there is still a structure-deficit, that is, most lipase structures are yet to be resolved. a search for 'lipase structure' in the rcsb protein data bank (http://www.rcsb.org/pdb/) returns only 93 hits (as o ...200819609386
enzymatic hydrolysis of soybean oil using lipase from different sources to yield concentrated of polyunsaturated fatty acids.the ability of three commercially available lipases to mediate the hydrolysis of the soybean oil to yield concentrated of essential fatty acids was evaluated. the tested lipases were from microbial (candida rugosa and thermomyces lanuginosa) and animal cells (porcine pancreatic lipase). in terms of free fatty acids, microbial lipases were more effective to promote the enzymatic hydrolysis of the soybean oil (over 70%) than the porcine pancreatic lipase (24%). in spite of this, porcine pancreatic ...200727517828
enhancement of lipase activity in non-aqueous media upon immobilization on multi-walled carbon nanotubes.immobilization of biologically active proteins on nanosized surfaces is a key process in bionanofabrication. carbon nanotubes with their high surface areas, as well as useful electronic, thermal and mechanical properties, constitute important building blocks in the fabrication of novel functional materials.200718047656
synthesis and characterization of canola oil-stearic acid-based trans-free structured lipids for possible margarine application.incorporation of stearic acid into canola oil to produce trans-free structured lipid (sl) as a healthy alternative to partially hydrogenated fats for margarine formulation was investigated. response surface methodology was used to study the effects of lipozyme rm im from rhizomucor miehei and candida rugosa lipase isoform 1 (lip1) and two acyl donors, stearic acid and ethyl stearate, on the incorporation. lipozyme rm im and ethyl stearate gave the best result. gram quantities of sls were synthes ...200718052237
lipolytic enzymes with improved activity and selectivity upon adsorption on polymeric nanoparticles.nanostructured polystyrene (ps) and polymethylmethacrylate (pmma) were used as carriers for the preparation of bioconjugates with lipolytic enzymes, such as candida rugosa lipase (crl) and pseudomonas cepacia lipase (pcl). simple addition of the lipase solution to the polymeric nanoparticles under protein-friendly conditions (ph 7.6) led to the formation of polymer-enzyme bioconjugates. energy filtered-transmission electron microscopy (ef-tem) performed on immuno-gold labeled samples revealed th ...200717803276
adsorption and activity of lipase from candida rugosa on the chitosan-modified poly(acrylonitrile-co-maleic acid) membrane surface.efforts have recently been made to improve the biocompatibility of support surface for enzyme immobilization, which could create a specific microenvironment for the enzymes and thus benefit the enzyme activity. in this work, one natural macromolecule, chitosan, was tethered on the surface of poly(acrylonitrile-co-maleic acid) (pancma) membrane to prepare a dual-layer biomimetic support for enzyme immobilization. lipase from candida rugosa was immobilized on this dual-layer biomimetic support by ...200717616362
synthesis of isoamyl laurate and isoamyl stearate in supercritical carbon dioxide.the synthesis of isoamyl laurate and isoamyl stearate was studied in supercritical carbon dioxide with three lipases, novozym 435, lipolase 100t, and candida rugosa. the maximum conversion of 37% and 53%, respectively for isoamyl laurate and isoamyl stearate was obtained when novozym 435 was used. the effect of various parameters such as molar ratio of alcohol to acid, presence of water, time and temperature was investigated. an optimum temperature of 40-45 degrees c was observed for all reactio ...200717625272
optimization of medium composition for lipase production by candida rugosa ncim 3462 using response surface methodology.a sequential optimization approach using statistical design of experiments was employed to enhance the lipase production by candida rugosa in submerged batch fermentation. twelve medium components were evaluated initially using the plackett-burman 2-level factorial design. the significant variables affecting lipase production were found to be glucose, olive oil, peptone, (nh4)2so4, and fecl3.6h2o. various vegetable oils were tested in the second step, and among them, groundnut oil was found to b ...200717668023
antifungal susceptibility of 1000 candida bloodstream isolates to 5 antifungal drugs: results of a multicenter study conducted in são paulo, brazil, 1995-2003.we evaluated all candida sp. bloodstream isolates obtained from patients admitted to 4 tertiary care hospitals between 1995 and 2003 in the city of são paulo, brazil. susceptibility to amphotericin b, 5-fluorocytosine, fluconazole (fcz), itraconazole (itz), and voriconazole (vcz) was determined using the clinical laboratory standards institute broth microdilution method. we tested a total of 1000 strains, including 400 strains of candida albicans (40%), 243 of candida tropicalis (24.3%), 238 of ...200717240110
acidolysis of tristearin with selected long-chain fatty acids.five lipases, namely, candida antarctica (novozyme-435), mucor miehei (lipozyme-im), pseudomonas sp. (ps-30), aspergillus niger (ap-12), and candida rugosa (ay-30), were screened for their effect on catalyzing the acidolysis of tristearin with selected long-chain fatty acids. among the lipases tested c. antarctica lipase catalyzed the highest incorporation of oleic acid (oa, 58.2%), gamma-linolenic acid (gla, 55.9%), eicosapentaenoic acid (epa, 81.6%), and docosahexaenoic acid (dha, 47.7%) into ...200717288439
an approach to address candida rugosa lipase regioselectivity in the acylation reactions of trytilated glucosides.candida rugosa lipase crude preparations (crl) catalyse the regioselective acylation of methyl 6-o-trytil beta-d-glucopyranoside in organic solvents, using vinyl acetate as acyl donor. the ratio of the two products formed, namely methyl 2-o acetyl 6-o-trytil beta-d-glucopyranoside and methyl 3-o acetyl 6-o-trytil beta-d-glucopyranoside was found to be markedly affected by the nature of the reaction medium. in hydrophobic solvents values up to 80% of the monoacetylated product in position c-3 wer ...200717321623
inhibition of rhizomucor miehei and candida rugosa lipases by d-glucose in esterification between l-alanine and d-glucose.a detailed kinetic study of the esterification of d-glucose with l-alanine catalyzed by lipases from rhizomucor miehei (rml) and candida rugosa (crl) showed that both lipases follow the ping-pong bi-bi mechanism, in which l-alanine and d-glucose bind in subsequent steps releasing water and l-alanyl-d-glucose, with competitive substrate inhibition by d-glucose at higher concentrations leading to the formation of dead-end lipase.d-glucose complexes. an attempt to obtain the best fit of this kineti ...200717368393
a parametric study on biphasic medium conditions for the enantioselective production of naproxen by candida rugosa lipase.a parametric study to increase the enantioselectivity of candida rugosa lipase (crl) toward s-naproxen production by the hydrolysis of racemic naproxen methyl ester in an aqueous-organic biphasic batch system was carried out. effects of organic solvent type, aqueous phase/organic solvent volume ratio, agitation rate, concentrations of the substrate and the enzyme, ph of the aqueous phase, and temperature on the enantiomeric excess for the product (eep), on the enantiomeric ratio (e) and on the c ...200717625263
an enzyme derivatized polydimethylsiloxane (pdms) membrane for use in membrane introduction mass spectrometry (mims).membrane introduction mass spectrometry (mims) provides direct measurement of volatile and semivolatile analytes in condensed and gas-phase samples without sample preparation steps. although mims has numerous advantages that include direct, on-line, real-time analysis with low detection limits, current applications of mims are predominantly limited to volatile and semivolatile analytes that permeate hydrophobic membranes (e.g., polydimethylsiloxane; pdms). we report the first enzyme modified pdm ...200717395478
candida rugosa lipase-catalyzed polyurethane degradation in aqueous medium.candida rugosa lipase (ec 3.1.1.3) was used to degrade commercially-available solid poly(ester)urethane (impranil) in an aqueous medium under different temperature, ph, enzyme and substrate concentrations. a mathematical model was developed and applied to represent the degradation kinetics of the solid polyurethane. reaction optima were found to be ph 7 and 35 degrees c. diethylene glycol, a degradation byproduct, generation rate was measured to be 0.12 mg/l min and the activation energy was cal ...200717450322
immobilization of candida rugosa lipase on magnetized dacron: kinetic study.candida rugosa lipase has been covalently immobilized on ferromagnetic azide polyethyleneterepthalate (dacron) with specific activity retention of 16% for 4-nitrophenyl palmitate and 24% for hydrolysis of triolein in hexane. the immobilized enzyme was more thermal stable than the soluble one, retaining 78.8% of the activity after 1 h at 60 degrees c. also, this immobilized derivative was stable at the storage at 4 degrees c. it has been used 5 cycles for pnpp hydrolysis without loss of activity. ...200717453706
a method for lipase co-precipitation in a biodegradable protein matrix.this article presents a novel method for immobilization of active ingredients. the method is based on co(2) aided active ingredient co-precipitation with glycinin, a biodegradable protein matrix from edible soybean protein. glycinin precipitates abundantly under isoelectric conditions and serves as the matrix within which the active substance is trapped during the precipitation process. the enzyme lipase from candida rugosa was successfully co-precipitated into the protein pellet to prove the pr ...200717514752
altering the substrate specificity of candida rugosa lip4 by engineering the substrate-binding sites.candida rugosa (formerly candida cylindracea) lipase (crl) is an important industrial enzyme that is widely used in biotechnological applications such as the production of fatty acids and the synthesis of various esters. crl comprises at least seven isozymes (lip1-lip7), which share a similar amino acid sequence but with different specificities for substrates. previously, lip4 was reported to have higher esterase activity toward long acyl-chain ester and lower lipase activity toward triglyceride ...200717536826
activation of candida rugosa lipase at alkane-aqueous interfaces: a molecular dynamics study.the effect of solvent hydrophobicity on activation of candida rugosa lipase (crl) was investigated by performing molecular dynamics simulations for four nano seconds (ns). the closed/inactive conformer of crl (pdb code 1trh) was solvated in three alkane-aqueous environments. the alkanes aggregated in a predominantly aqueous environment and by 1 ns a stable spherical alkane-aqueous interface had formed. this led to the interfacial activation of crl. on analyzing the simulated conformers with the ...200717765226
prospective observational study of candidemia in são paulo, brazil: incidence rate, epidemiology, and predictors of mortality.studies conducted in tertiary care hospitals of different european countries and the united states have shown incidence rates of candidemia ranging from 0.17 to 0.76 and 0.28 to 0.96 per 1,000 admissions, respectively. so far, only 1 study has evaluated the incidence rates of candidemia in tertiary care hospitals in latin american countries.200717464917
a water activity control system for enzymatic reactions in organic media.a water activity control system for enzymatic synthesis in organic media, for litre-scale reactors has been constructed. water activity, a(w), is a key factor when using enzymes in non-conventional media and the optimum value varies for different enzymes. the control system consists of a water activity sensor in the headspace of a jacketed glass reactor (equipped with narrow steel tubes to introduce air), gas-washing bottles containing blue silica gel (a(w)=0) and water (a(w)=1), a pc to monitor ...200717096388
kinetic resolution of (+/-)-1-phenylethanol in [bmim][pf6] using high activity preparations of lipases.lipases from two different sources candida rugosa (crl) and burkholderia cepacia (bcl) were formulated as enzyme precipitated and rinsed with organic solvents, organic solvent rinsed enzyme preparation, cross-linked enzyme aggregates (cleas) and protein coated micro-crystals (pcmcs). these various enzyme formulates were evaluated for the kinetic resolution of (+/-)-1-phenylethanol in ionic liquid [bmim][pf(6)] by transesterification with vinyl acetate. of all the enzyme forms evaluated eprp and ...200717157018
hofmeister effects in enzymatic activity: weak and strong electrolyte influences on the activity of candida rugosa lipase.the effects of weak and strong electrolytes on the enzymatic activity of candida rugosa lipase are explored. weak electrolytes, used as buffers, set the ph, while strong electrolytes regulate the ionic strength. the interplay between ph and ionic strength has been assumed to be the determinant of enzymatic activity. in experiments that probe activities by varying these parameters, there has been little attention focused on the role of specific electrolyte effects. here we show that both buffers ...200717266269
characterization of lipase in reversed micelles formulated with cibacron blue f-3ga modified span 85.sorbitan trioleate (span 85) modified by cibacron blue f-3ga (cb) was prepared and used as an affinity surfactant to formulate a reversed micellar system for candida rugosa lipase (crl) solubilization. the system was characterized and evaluated by employing crl-catalyzed hydrolysis of olive oil as a model reaction. the micellar hydrodynamic radius results reflected, to some extent, the redistribution of surfactant and water after enzyme addition, and the correlation between surfactant formulatio ...200717269677
impact of aluminum on the oxidation of lipids and enzymatic lipolysis in monomolecular films at the air/water interface.there is evidence that serious pathologies are associated with aluminum (al). in the present work, the influence of al on enzymatic lipolysis was studied with the aim to get more insight into the possible link between the al-induced membrane modification and the cytotoxicity of the trivalent cation (aliii). lipid monolayers were used as model membranes. the monomolecular film technique allowed monitoring the al-dependent modifications of the lipid monolayer properties and enzyme kinetics. two en ...200717279785
peptidase profiles from non-albicans candida spp. isolated from the blood of a patient with chronic myeloid leukemia and another with sickle cell disease.candida lipolytica and candida rugosa were isolated from blood samples from a patient with chronic myeloid leukemia (31 years old) and a patient with sickle cell disease (1-year-old), respectively. isolates were grown for 48 h at 37 degrees c in either sabouraud or tryptone soy broth (tsb). peptidases were tested for using substrate sodium dodecyl sulfate-polyacrylamide gels with gelatin, casein, bovine serum albumin (bsa) or hemoglobin. enzymography analyses were made on the following substrate ...200717559410
internal transcribed spacer sequencing versus biochemical profiling for identification of medically important yeasts.in this study, we established an in-house database of yeast internal transcribed spacer (its) sequences. this database includes medically important as well as colonizing yeasts that frequently occur in the diagnostic laboratory. in a prospective study, we compared molecular identification with phenotypic identification by using the id32c system (biomérieux) for yeast strains that could not be identified by a combination of chromagar candida and morphology on rice agar. in total, 113 yeast strain ...200616390952
microscopic analysis of ester hydrolysis reaction catalyzed by candida rugosa lipase.the relationship between the kinetics of the lipase-catalyzed oil hydrolysis and the surface area distribution of oil droplets was investigated using ethyl decanoate and gum arabic (ga) as a model oil and an emulsifier, respectively. along an ethyl decanoate concentration gradient between 2 and 8 mm, the initial hydrolysis rate increased at 0.25% (w/v) ga but did not change at 1.0% (w/v) ga. at 0.25% ga, the surface area of droplets was narrowly distributed regardless of the ethyl decanoate conc ...200616406517
codon optimization of candida rugosa lip1 gene for improving expression in pichia pastoris and biochemical characterization of the purified recombinant lip1 lipase.an important industrial enzyme, candida rugosa lipase (crl) possesses several different isoforms encoded by the lip gene family (lip1-lip7), in which the recombinant lip1 is the major form of the crl multigene family. previously, 19 of the nonuniversal serine codons (ctg) of the lip1 gene hav been successfully converted into universal serine codons (tct) by overlap extension pcr-based multiple-site-directed mutagenesis to express an active recombinant lip1 in the yeast pichia pastoris. to improv ...200616448188
application of sscp-pcr fingerprinting to profile the yeast community in raw milk salers cheeses.bacteria and yeasts are important sensory factors of raw-milk cheeses as they contribute to the sensory richness and diversity of these products. the diversity and succession of yeast populations in three traditional registered designation of origin (r.d.o.) salers cheeses have been determined by using phenotypic diagnoses and single-strand conformation polymorphism (sscp) analysis. isolates were identified by phenotypic tests and the sequencing of the d1-d2 domains of the 26s rrna gene. ninety- ...200616464699
pre-treatment of high oil and grease pet food industrial wastewaters using immobilized lipase hydrolyzation.wastewaters generating from pet food industries contain high concentration of oil and grease (o&g), which is difficult to treat through conventional biological treatment systems. in this study, the hydrolysis of o&g originating from pet food industrial wastewater was evaluated. candida rugosa lipase was immobilized in calcium alginate beads and applied in the hydrolysis experiment. results showed that approximately 50% of the o&g was hydrolyzed due to the enzyme activity. a significant increment ...200616504384
efficient hydrolysis of tuna oil by a surfactant-coated lipase in a two-phase system.a surfactant-coated lipase (scl) prepared by mixing candida rugosa lipase with emulsifier in ethanol was used to hydrolyze tuna oil in a two-phase aqueous-organic system. both enzyme (scl) and substrate (tuna oil) were soluble in the organic phase, and the hydrolysis could occur with water molecules from the aqueous phase. this hydrolysis could promptly proceed compared to that catalyzed by native lipases which only occurred at the interface between the two phases. michaelis-menten kinetics in t ...200616506843
nanofibrous poly(acrylonitrile-co-maleic acid) membranes functionalized with gelatin and chitosan for lipase immobilization.nanofibrous membranes with an average diameter of 100 and 180 nm were fabricated from poly(acrylonitrile-co-maleic acid) (pancma) by the electrospinning process. these nanofibrous membranes contain reactive groups which can be used to covalently immobilize biomacromolecules. two natural macromolecules, chitosan and gelatin, were tethered on these nanofibrous membranes to fabricate dual-layer biomimetic supports for enzyme immobilization in the presence of 1-ethyl-3-(dimethyl-aminopropyl) carbodi ...200616584770
atomic force microscope studies on the interactions of candida rugosa lipase and supported lipidic bilayers.using the langmuir-blodgett technique we prepared substrate supported well-defined lipid/phospholipid (1-mono-palmitoyl-rac-glycerol (mpg)/l,2-dipalmitoyl-sn-glycerol-3-phosphocholine (dppc)) bilayers in which the mpg lipid leaflet was exposed to the aqueous phase. hydrolysis of mpg performed by candida rugosa lipase (crl) on the upper mpg layer of these supported bilayers on mica was imaged by real time atomic force microscope (afm) using a liquid cell, so that the area increase of the initial ...200616829060
studies of reaction parameters on synthesis of citronellyl laurate ester via immobilized candida rugosa lipase in organic media.immobilized candida rugosa lipase was used for the synthesis of citronellyl laurate from citronellol and lauric acid. screening of different types of support (amberlite mb-1 and celite) for immobilization of lipase and solvent (n-hexane, n-heptane, and iso-octane) and optimization of reaction conditions, such as catalyst loading, effect of substrates molar ratio and temperature, have been studied. the maximum enzyme activity was obtained at 310 k. the immobilized c. rugosa lipase onto amberlite ...200616868763
candida rugosa lipase lip1-catalyzed transesterification to produce human milk fat substitute.structured lipids (sls) containing palmitic and oleic acids were synthesized by transesterification of tripalmitin with either oleic acid or methyl oleate as acyl donor. this sl with palmitic acid at the sn-2 position and oleic acid at sn-1,3 positions is similar in structure to human milk fat triacylglycerol. lip1, an isoform of candida rugosa lipase (crl), was used as biocatalyst. the effects of reaction temperature, substrate molar ratio, and time on incorporation of oleic acid were investiga ...200616819932
lipase-catalyzed esterification of 2-monoricinolein for 1,2 (2,3)-diricinolein synthesis.the purpose of this investigation was to develop conditions for producing 2-monoricinoleoyl dag. we used lipase-catalyzed hydrolysis of triricinolein to obtain 2-monoricinolein and thereafter synthesized 1,2(2,3)-diricinolein through esterification of 2-monoricinolein, using ricinoleic acid as the acyl donor. five different 1,3-specific immobilized lipases were tested for the initial methanolysis reaction: candida antarctica type b, rhizomucor miehei, rhizopus oryzae (rol), thermomyces lanuginos ...200616555475
efficient production of active recombinant candida rugosa lip3 lipase in pichia pastoris and biochemical characterization of the purified enzyme.candida rugosa lipase (crl), an important industrial enzyme, possesses several different isoforms encoded by the high-identity lip gene family (lip1 to lip7). in this study, an additional n-terminal peptide in front of the lip3 gene was removed by pcr, and the 18 nonuniversal serine codons (ctg) of the lip3 gene were converted into universal serine codons (tct) by means of an overlap extension pcr-based multiple-site-directed mutagenesis to express an active recombinant lip3 in the yeast pichia ...200616881684
optimized growth kinetics of pichia pastoris and recombinant candida rugosa lip1 production by rsm.a predictive model for pichia pastoris expression of highly active recombinant candida rugosa lip1 was developed by combining the gompertz function and response surface methodology (rsm) to evaluate the effect of yeast extract concentration, glucose concentration, temperature, and ph on specific responses. each of the responses (maximum population densities, specific growth rate (mumax), protein concentration, and minimum lag phase duration) was determined using the modified gompertz function. r ...200616825788
glutaraldehyde cross-linking of lipases adsorbed on aminated supports in the presence of detergents leads to improved performance.lipases from candida rugosa (crl) and lipase isoforms a and b from candida antarctica (cal-a and cal-b) were adsorbed on aminated supports in the presence of detergents to have individual lipase molecules. then, one fraction was washed to eliminate the detergent, and both preparations were treated with glutaraldehyde. the presence of detergent during the cross-linking of the lipases to the support permitted an increase in the recovered activity (in some instances, even by a 10-fold factor). this ...200616961324
candida rugosa, an emerging fungal pathogen with resistance to azoles: geographic and temporal trends from the artemis disk antifungal surveillance program.candida rugosa is a fungus that appears to be emerging as a cause of infection in some geographic regions. we utilized the extensive database of the artemis disk antifungal surveillance program to describe the geographic and temporal trends in the isolation of c. rugosa from clinical specimens and the in vitro susceptibilities of 452 isolates to fluconazole and voriconazole. c. rugosa accounted for 0.4% of 134,715 isolates of candida, and the frequency of isolation increased from 0.03% to 0.4% o ...200617021085
increased enantioselectivity and remarkable acceleration of lipase-catalyzed transesterification by using an imidazolium peg-alkyl sulfate ionic liquid.several types of imidazolium salt ionic liquids were prepared derived from poly(oxyethylene)alkyl sulfate and used as an additive or coating material for lipase-catalyzed transesterification in an organic solvent. a remarkably increased enantioselectivity was obtained when the salt was added at 3-10 mol % versus substrate in the burkholderia cepacia lipase (lipase ps-c)-catalyzed transesterification of 1-phenylethanol by using vinyl acetate in diisopropyl ether or a hexane solvent system. in par ...200617029309
acidolysis and glyceride synthesis reactions using fatty acids with two pseudomonas lipases having different substrate specificities.enzymatic acidolysis and glyceride synthesis using polyunsaturated fatty acids (pufas) with lipases from pseudomonas fluorescens hu380 (hu-lipase), p. fluorescens ak102 (ak-lipase), and candida rugosa (cr-lipase) were studied. the acidolysis of triolein with eicosapentaenoic acid (epa) or docosahexaenoic acid (dha) in n-hexane was evaluated with lipases immobilized on celite 545. hu-lipase showed the highest incorporation rate at a low temperature (10 degrees c) with either epa or dha as the acy ...200617046530
investigating ph and cu (ii) effects on lipase activity and enantioselectivity via kinetic and spectroscopic methods.for candida rugosa lipase (crl) catalyzed hydrolysis of racemic 1-phenethyl acetate, both the weakly acidic ph (ph 6.0) and the addition of 1 mm copper (ii) ion enhanced the enzyme activity and enantioselectivity (e value) about twofold, as compared with that under neutral ph and noadditive conditions. the decrease of activation free energy (deltag) and increase of k(cat)(r)/k(cat)(s) at weakly acidic ph and/or in the presence of copper (ii) characterized the kinetic behavior of crl. on the othe ...200617068757
a novel reactive perstraction system based on liquid-core microcapsules applied to lipase-catalyzed biotransformations.a novel reactive perstraction system has been developed based on liquid-core capsules, involving an enzyme-catalyzed reaction coupled with simultaneous in situ product recovery. lipase-catalyzed reactions, hydrolysis of triprionin and nitrophenyl laurate, were selected to test the system and demonstrate the feasibility of immobilization of enzymes to the membranes of liquid-core capsules and the ability to extract hydrophobic products of the reaction within the capsule core. the lipase from cand ...200616136589
synthesis of structured lipids containing medium-chain and omega-3 fatty acids.the ability of different lipases to incorporate omega3 fatty acids, namely, eicosapentaenoic acid (epa, c20:5n-3), docosapentaenoic acid (dpa, c22:5n-3), and docosahexaenoic acid (dha, c22:6n-3), into a high-laurate canola oil, known as laurical 35, was studied. lipases from mucor miehei (lipozyme-im), pseudomonas sp. (ps-30), and candida rugosa (ay-30) catalyzed optimum incorporation of epa, dpa, and dha into laurical 35, respectively. other lipases used were candida anatrctica (novozyme-435) a ...200616756372
understanding candida rugosa lipases: an overview.candida rugosa lipase (crl) is one of the enzymes most frequently used in biotransformations. however, there are some irreproducibility problems inherent to this biocatalyst, attributed either to differences in lipase loading and isoenzymatic profile or to other medium-engineering effects (temperature, a(w), choice of solvent, etc.). in addition, some other properties (influence of substrate and reaction conditions on the lid movement, differences in the glycosylation degree, post-translational ...200616288844
the acetates of p-nitrophenyl alpha-l-arabinofuranoside--regioselective preparation by action of lipases.all possible di-o-acetates and mono-o-acetates of p-nitrophenyl alpha-l-arabinofuranoside were prepared by chemoenzymatic way using lipases. the 2,3-di-o-acetate was obtained in 90% yield by deacetylation of the primary acetyl group of per-o-acetylated p-nitrophenyl alpha-l-arabinofuranoside by candida cylindracea lipase (ccl) or candida rugosa lipase (lay). the 2,5- and 3,5-di-o-acetates were obtained by acetylation of p-nitrophenyl alpha-l-arabinofuranoside by pseudomonas cepacia lipase (lps-3 ...200616288881
a secreted lipase encoded by lip1 is necessary for efficient use of saturated triglyceride lipids in fusarium graminearum.a triglyceride lipase gene lip1 was identified in the genome of fusarium graminearum strain ph-1. the predicted protein encoded by lip1 contains 591 amino acid residues with a putative n-terminal signal peptide and shows 57 and 40-44 % identity to a botrytis cinerea lipase and five candida rugosa lipases, respectively. yeast cells overexpressing lip1 showed lipolytic activity against a broad range of triglyceride substrates. northern blot analyses revealed that expression of lip1 was activated i ...200516339936
fabrication and application of enzyme-incorporated peptide nanotubes.enzyme engineering is a fast-growing field in the pharmaceutical and food markets. for those applications, various substrates have been examined to immobilize and stabilize enzymes. in this report, we examined peptide nanotubes as supports for enzymes. when a model enzyme, candida rugosa lipase, was encapsulated in peptide nanotubes, the catalytic activity of nanotube-bound lipases was increased 33% as compared to free-standing lipases at room temperature. at an elevated temperature, 65 degrees ...200516287245
superparamagnetic nanoparticle-supported enzymatic resolution of racemic carboxylates.candida rugosa lipase immobilized on maghemite nanoparticles demonstrated high stereoselectivity in kinetic resolution of racemic carboxylates and improved long-term stability over its parent free enzyme, allowing the supported enzyme to be repeatedly used for a series of chiral resolution reactions.200516136241
enzymatic procedures in the preparation of regioprotected d-fructose derivatives.a combination of different lipases from pseudomonas cepacia, candida antarctica b, candida rugosa and mucor miehei, aided the regioesterification of the free fructose allowing the synthesis of 1,6-di-o-acetyl-d-fructofuranose, 1,4,6-tri-o-acetyl-d-fructofuranose, 1,6-di-o-acetyl-4-o-benzoyl-d-fructofuranose and 1,6-di-o-benzoyl-d-fructofuranose. using c. antarctica b and c. rugosa lipases the alcoholysis of fructose peracetate (alpha, beta-form) has furnished 1,2,3,4-tetra-o-acetyl-alpha-d-fruct ...200515639253
a supported liquid membrane encapsulating a surfactant-lipase complex for the selective separation of organic acids.we have developed a novel, lipase-facilitated, supported liquid membrane (slm) for the selective separation of organic acids by encapsulating a surfactant-lipase complex in the liquid membrane phase. this system exhibited a high transport efficiency for 3-phenoxypropionic acid and enabled the selective separation of organic acids due to the different solubilities of the acids in the organic phase and the variable substrate specificity of the surfactant-lipase complex in the liquid membrane phase ...200515645485
characterization of sol-gel bioencapsulates for ester hydrolysis and synthesis.candida rugosa lipase was entrapped in silica sol-gel particles prepared by hydrolysis of methyltrimethoxysilane and assayed by p-nitrophenyl palmitate hydrolysis, as a function of ph and temperature, giving ph optima of 7.8 (free enzyme) and 5.0-8.0 (immobilized enzyme). the optimum temperature for the immobilized enzyme (50-55 degrees c) was 19 degrees c higher than for the free enzyme. thermal, operational, and storage stability were determined with n-butanol and butyric acid, giving at 45 de ...200515930564
secondary structure, conformational stability and glycosylation of a recombinant candida rugosa lipase studied by fourier-transform infrared spectroscopy.the secondary structure of lipase 1 from candida rugosa, a model system for large monomeric enzymes, has been studied by ftir (fourier-transform infrared) spectroscopy in water and 2h2o. the secondary structure content, determined by the analysis of the amide i band absorption through second derivative and curve fitting procedures, is in agreement with that estimated by x-ray data and predicts, in addition, the existence of two classes of alpha-helices. we have also investigated the enzyme stabi ...200515362976
kinetic resolution of ibuprofen catalyzed by candida rugosa lipase in ionic liquids.candida rugosa lipase-catalyzed esterification of ibuprofen with 1-propanol was conducted in seven ionic liquids and the results were compared with those in isooctane. although the enzyme showed comparable or higher activity in some ionic liquids compared to that in isooctane, only in the case of [bmim]pf6 was the enantioselectivity (e = 24.1) almost twice that (e = 13.0) of isooctane. in another six ionic liquids the enzyme enantioselectivity was much poorer (e = 1.1-6.4). at the same conversio ...200515515047
high-yield conversion of (r)-2-octanol from the corresponding racemate by stereoinversion using candida rugosa.whole cells of candida rugosa catalyzed the conversion of (r)-2-octanol from the corresponding racemate with the optical purity of 97% e.e. and yield of 92% in 10 h. the product was formed through a stereoinversion involving enantioselective oxidation and asymmetric reduction with 2-octanone as the intermediate.200515685415
hydrolytic resolution of (r,s)-naproxen 2,2,2-trifluoroethyl thioester by carica papaya lipase in water-saturated organic solvents.for the first time, the carica papaya lipase (cpl) stored in crude papain is explored as a potential enantioselective biocatalyst for obtaining chiral acids from their racemic thioesters. hydrolytic resolution of (r,s)-naproxen 2,2,2-trifluoroethyl thioester in water-saturated organic solvents is employed as a model system for studying the effects of temperature and solvents on lipase activity and enantioselectivity. an optimal temperature of 60 degrees c, based on the initial rate of (s)-thioes ...200515543625
highly active, lipase silicone elastomers.lipase candida rugosa was entrapped in silicone rubber via condensation-cure room temperature vulcanization of silanol-terminated poly(dimethylsiloxane) with tetraethyl orthosilicate as a crosslinker, to give a highly active silicone-enzyme elastomer. the effect on enzyme activity of addition of water and hydrophilic polymeric moieties based on poly(ethylene oxide) 2 was examined, as were crosslinker concentration, enzyme concentration, and elastomer thickness. it was demonstrated that lipase is ...200515576139
continuous monitoring of cholesterol oleate hydrolysis by hormone-sensitive lipase and other cholesterol esterases.hormone-sensitive lipase (hsl) contributes importantly to the hydrolysis of cholesteryl ester in steroidogenic tissues, releasing the cholesterol required for adrenal steroidogenesis. hsl has broad substrate specificity, because it hydrolyzes triacylglycerols (tags), diacylglycerols, monoacylglycerols, and cholesteryl esters. in this study, we developed a specific cholesterol esterase assay using cholesterol oleate (co) dispersed in phosphatidylcholine and gum arabic by sonication. to continuous ...200515716583
immobilization of candida rugosa lipase on a ph-sensitive support for enantioselective hydrolysis of ketoprofen ester.candida rugosa lipase (lipase of) was immobilized by covalent binding to a ph-sensitive support showing reversibly soluble-insoluble characteristics with ph change. the immobilized lipase could carry out the enantioselective hydrolysis of ketoprofen ester in a soluble form yet be recovered after precipitation by simply adjusting ph. its activity and enantioselectivity for hydrolysis of 2-chloroethyl ester of ketoprofen were enhanced 1.5-fold and 8.7-fold compared with those of free lipase. after ...200515748766
frequent analytical/experimental problems in lipase-mediated synthesis in solvent-free systems and how to avoid them.compared with chemical catalysis, enzymatic catalysis is a relatively new topic. experimental work involving lipases deserves careful attention and accurate procedures still need to be implemented. a rapid but careful survey of published data immediately demonstrates that experiments performed under similar conditions with similar reagents have led to very different results. the aim of this work is to point out the importance of accurate and systematic procedures in order to ensure the reproduci ...200515789246
candida rugosa lipase-catalyzed intramolecular o- to n- transacylation of butyryl propranolol in the presence of cyclodextrins.in the present paper, a novel enzymatic reaction between (r,s)-o-butyryl propranolol (o-bp) and lipase from candida rugosa in the presence of hydroxypropyl-beta-cyclodextrin (hp-beta-cd) is described. under the used condition, lipase catalyzed the intramolecular transacylation of o-bp into n-butyryl propranolol (n-bp). propranolol, the product of the expected hydrolysis reaction, was not detected in the reaction medium. a chiral analysis of the reaction product indicated that lipase showed a pre ...200515801768
enzymatic resolution of (+/-)-5-acetoxy-4-aryl-(2e)-pentenoate derivatives.enzymatic resolution of six (+/-)-5-acetoxy-4-aryl-(2e)-pentenoate derivatives, compounds 9, 11, 13, 15, 17, and 19 bearing a different aromatic substitution pattern, using lipase of-360 from candida rugosa was carried out. the absolute configurations of all hydrolyzed products and all unchanged acetates were found to be s and r, respectively. moreover, the enantiomeric excess of the enzymatic resolution products from 9, 11, and 13 with the ortho-methoxyl group in the aromatic ring was higher th ...200515863931
partially purified carica papaya lipase: a versatile biocatalyst for the hydrolytic resolution of (r,s)-2-arylpropionic thioesters in water-saturated organic solvents.with the hydrolytic resolution of (r,s)-naproxen 2,2,2-trifluoroethyl thioesters in water-saturated isooctane as a model system, improvements of the specific lipase activity and thermal stability were found when a crude carica papaya lipase (cpl) was partially purified and employed as the biocatalyst. the partially purified carica papaya lipase (pcpl) was furthermore explored as an effective enantioselective biocatalyst for the hydrolytic resolution of (r,s)-profen thioesters in water-saturated ...200515918166
outbreak of candida rugosa mastitis in a dairy herd after intramammary antibiotic treatment. 200515965006
chitosan-tethered poly(acrylonitrile-co-maleic acid) hollow fiber membrane for lipase immobilization.a protocol was used to prepare a dual-layer biomimetic membrane as support for enzyme immobilization by tethering chitosan on the surface of poly(acrylonitrile-co-maleic acid) (pancma) ultrafiltration hollow fiber membrane in the presence of 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride (edc)/n-hydroxylsuccin-imide (nhs). the chemical change of the chitosan-modified pancma membrane surface was confirmed with fourier transform infrared spectroscopy and x-ray photoelectron spectroscop ...200515919112
an extracellular carboxylesterase from the basidiomycete pleurotus sapidus hydrolyses xanthophyll esters.an extracellular enzyme capable of efficient hydrolysis of xanthophyll esters was purified from culture supernatants of the basidiomycete pleurotus sapidus. under native conditions, the enzyme exhibited a molecular mass of 430 kda, and sds-page data suggested a composition of eight identical subunits. biochemical characterisation of the purified protein showed an isoelectric point of 4.5, and ideal hydrolysis conditions were observed at ph 5.8 and 40 degrees c. partial amino acid sequences were ...200515927887
wood cellulignin as an alternative matrix for enzyme immobilization.the objective of this work was to select an efficient methodology for preparing active samples of candida rugosa lipase immobilized in wood cellulignin, to be applied in hydrolysis and ester reactions. for this purpose, lipase was immobilized in the matrix by physical adsorption (pure cellulignin) and covalent binding (activated cellulignin with glutaraldeyde or carbonyldiimidazole [cdi]) in the presence or absence of polyethylene glycol (peg) (molecular mass of 1500 daltons) as stabilizing agen ...200515917604
rational strategy for the production of new crude lipases from candida rugosa.candida rugosa was cultured using different inducers (oleic acid, olive oil, sunflower oil, n-dodecanol and glycerol) as the only carbon source in batch conditions, as well as in several fed-batch fermentations (oleic acid as inducer) at variable feed rate conditions. the n-terminal analysis of each crude lipase revealed that, while the isoenzymes lip2 and lip3 are always secreted (at different proportions depending on the inducer), lip1 was produced only using n-dodecanol (batch conditions) or ...200515928857
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