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bio-based production of dimethyl itaconate from rice wine waste-derived itaconic acid.dimethyl itaconate is an important raw material for copolymerization, but it is not synthesized from itaconic acid by organisms. moreover, corynebacterium glutamicum is used as an important industrial host for the production of organic acids, but it does not metabolize itaconic acid. therefore, the biosynthetic route towards dimethyl itaconate from itaconic acid is highly needed. in this study, we developed a biological procedure for dimethyl itaconate production from rice wine waste-derived ita ...201728846199
lipase-catalyzed synthesis of oleoyl-lysophosphatidylcholine by direct esterification in solvent-free medium without water removal.in this work, the synthesis of oleoyl-lysophosphatidylcholine by lipase-catalyzed esterification of glycerophosphocholine (gpc) and free oleic acid in a reaction medium without solvent is presented. the complete solubilisation of gpc, which is a crucial issue in non-polar liquids such as melted free fatty acids, was reached by heating the gpc/oleic acid mixture at high temperature during a short time. the immobilized lipase from rhizomucor miehei (lipozyme rm-im) was shown to catalyze the reacti ...201728794312
co-expression of lipase isozymes for enhanced expression in pichia pastoris.to enhance the expression level of overall lipase isozymes which catalyze the same reaction in p. pastoris through co-expression of isozymes from different sources, several types of co-expression ways were constructed to determine the co-expression efficiencies of lipase isozymes in p. pastoris. the results showed that the kex2 mediated co-expression of lipase isozymes could express rhizomucor miehei lipase (rml) and thermomyces lanuginosus lipase (tll) simultaneously, and gs-rmk-ktl displayed a ...201728763110
high level expression of β-mannanase (rmman5a) in pichia pastoris for partially hydrolyzed guar gum production.partially hydrolyzed guar gum (phgg), an important supplemental dietary fiber, has been used as food ingredient in many industries. in this study, a novel β-mannanase gene (rmman5a) from rhizomucor miehei was successfully expressed in pichia pastoris and subjected for phgg production. enzyme activity of fermentation supernatant reached 85,200uml(-1) after 168h high cell density fermentation. the purified rmman5a exhibited the highest enzyme activity at ph 7.0 and 65°c. rmman5a was then employed ...201728756198
immobilization of rhizomucor miehei lipase on a polymeric film for synthesis of important fatty acid esters: kinetics and application studies.the present work deals with the designing of biocompatible hybrid blend of cellulosic copolymers made of hydroxypropyl methylcellulose (hmc) and chitosan (chi) for immobilization of rhizomucor miehei lipase (rml), in order to construct the robust biocatalytic system to synthesize industrially important dodecanoate compounds (fatty acid esters). the present biocatalyst hmc:chi:rml was characterized in detail by various physical and biochemical methods and subsequently applied for the synthesis of ...201728676893
improved activity of lipase immobilized in microemulsion-based organogels for (r, s)-ketoprofen ester resolution: long-term stability and reusability.microemulsion-based organogels (mbgs) were effectively employed for the immobilization of four commonly used lipases. during the asymmetric hydrolysis of ketoprofen vinyl ester at 30 °c for 24 h, lipase from rhizomucor miehei and mucor javanicus immobilized in microemulsion-based organogels (rml mbgs and mjl mbgs) maintained good enantioselectivities (eep were 86.2% and 99.2%, respectively), and their activities increased 12.8-fold and 7.8-fold, respectively, compared with their free forms. they ...201528626708
directed evolution of a β-mannanase from rhizomucor miehei to improve catalytic activity in acidic and thermophilic conditions.β-mannanase randomly cleaves the β-1,4-linked mannan backbone of hemicellulose, which plays the most important role in the enzymatic degradation of mannan. although the industrial applications of β-mannanase have tremendously expanded in recent years, the wild-type β-mannanases are still defective for some industries. the glycoside hydrolase (gh) family 5 β-mannanase (rmman5a) from rhizomucor miehei shows many outstanding properties, such as high specific activity and hydrolysis property. howeve ...201728588644
biophysical evaluation of milk-clotting enzymes processed by high pressure.high pressure processing (hpp) is able to promote changes in enzymes structure. this study evaluated the effect of hp on the structural changes in milk-clotting enzymes processed under activation conditions for recombinant camel chymosin (212mpa/5min/10°c), calf rennet (280mpa/20min/25°c), bovine rennet (222mpa/5min/23°c), and porcine pepsin (50mpa/5min/20°c) and under inactivation conditions for all enzymes (600mpa/10min/25°c) including the protease from rhizomucor miehei. in general, it was fo ...201728578031
establishment and application of a modified membrane-blot assay for rhizomucor miehei lipases aimed at improving their methanol tolerance and thermostability.directed evolution has been proved an effective way to improve the stability of proteins, but high throughput screening assays for directed evolution with simultaneous improvement of two or more properties are still rare. in this study, we aimed to establish a membrane-blot assay for use in the high-throughput screening of rhizomucor miehei lipases (rmls). with the assistance of the membrane-blot screening assay, a mutant e47k named g10 that showed improved thermal stability was detected in the ...201728465058
the first description of a hormone-sensitive lipase from a basidiomycete: structural insights and biochemical characterization revealed bjerkandera adusta baestb as a novel esterase.the heterologous expression and characterization of a hormone-sensitive lipases (hsl) esterase (baestb) from the basidiomycete fungus bjerkandera adusta is reported for the first time. according to structural analysis, amino acid similarities and conservation of particular motifs, it was established that this enzyme belongs to the (hsl) family. the cdna sequence consisted of 969 nucleotides, while the gene comprised 1133, including three introns of 57, 50, and 57 nucleotides. through three-dimen ...201728251842
enzymatic and solid-phase synthesis of new donepezil-based l- and d-glutamic acid derivatives and their pharmacological evaluation in models related to alzheimer's disease and cerebral ischemia.previously, we have described n-bz-l-glu[nh-2-(1-benzylpiperidin-4-yl)ethyl]-o-nhex (iqm9.21, l-1) as an interesting multifunctional neuroprotective compound for the potential treatment of neurodegenerative diseases. here, we describe new derivatives and different synthetic routes, such as chemoenzymatic and solid-phase synthesis, aiming to improve the previously described route in solution. the lipase-catalysed amidation of l- and d-glu diesters with n-benzyl-4-(2-aminoethyl)piperidine has been ...201728242552
ultrasound pretreatment as a novel approach for intensification of lipase catalyzed esterification of tricaprylin.the current work deals with ultrasound assisted intensification of synthesis of tricaprylin based on the enzyme catalyzed reaction of caprylic acid and glycerol with novel approach of using ultrasound in only the initial stages of the reaction. two types of immobilized lipases as lipozyme rm (rhizomucor miehei) and novozym 435 (candida antarctica) have been used in the work. the effect of ultrasonic conditions such as treatment time and power as well as the reaction conditions such as substrate ...201728069208
desorption of lipases immobilized on octyl-agarose beads and coated with ionic polymers after thermal inactivation. stronger adsorption of polymers/unfolded protein composites.lipases from candida antarctica (isoform b) and rhizomucor miehei (calb and rml) have been immobilized on octyl-agarose (oc) and further coated with polyethylenimine (pei) and dextran sulfate (ds). the enzymes just immobilized on oc supports could be easily released from the support using 2% sds at ph 7, both intact or after thermal inactivation (in fact, after inactivation most enzyme molecules were already desorbed). the coating with pei and ds greatly reduced the enzyme release during thermal ...201728067789
purification and properties of extracellular lipases with transesterification activity and 1,3-regioselectivity from rhizomucor miehei and rhizopus oryzae.rhizomucor miehei nrrl 5282 and rhizopus oryzae nrrl 1526 can produce lipases with high synthetic activities in wheat bran-based solid-state culture. in this study, the purification and biochemical characterization of the lipolytic activities of these lipases are presented. sds-page indicated a molecular mass of about 55 and 35 kda for the purified r. miehei and rh. oryzae enzymes, respectively. p-nitrophenyl palmitate (pnpp) hydrolysis was maximal at 40°c and ph 7.0 for the r. miehei lipase, an ...201727780957
production of biodiesel from acid oil via a two-step enzymatic transesterification.a two-step enzymatic transesterification process in a solvent-free system has been developed as a novel approach to the production of biodiesel using acid oil from rice bran oil soapstock. the acid oil consisted of 53.7 wt% fatty acids, 2.4 wt% monoacylglycerols, 9.1 wt% diacylglycerols, 28.8 wt% triacylglycerols, and 6.0 wt% others. three immobilized lipases were evaluated as potential biocatalysts, including novozym 435 from candida antarctica, lipozyme rm im from rhizomucor miehei, and lipozy ...201627733740
oxidation stability of o/w emulsion prepared with linolenic acid enriched diacylglycerol.the sn-1,3-regiospecific rhizomucor miehei lipase (lipozyme rm im) was employed to produce structured diacylglycerol (sl-dag), which contained 67.3 mol% dag with 27.2 area% of c18:3. to investigate the oxidative stability of the sl-dag in emulsion form, 5% oil-in-water (o/w) emulsions were prepared with 200 and 400 ppm sinapic acid. it was shown that the hydroperoxide values of the control (without any antioxidant) was the highest (117.7 meq/l) on day 43 of storage and thereafter the value decre ...201627627797
tailoring the internal structure of liquid crystalline nanoparticles responsive to fungal lipases: a potential platform for sustained drug release.lipases are key components in the mechanisms underlying the persistence and virulence of infections by fungi, and thus also promising triggers for bioresponsive lipid-based liquid crystalline nanoparticles. we here propose a platform in which only a minor component of the formulation is susceptible to cleavage by lipase and where hydrolysis triggers a controlled phase transition within the nanoparticles that can potentially allow for an extended drug release. the responsive formulations were com ...201627518452
interfacial activation of lipases on hydrophobic support and application in the synthesis of a lubricant ester.n-octyl oleate was synthetized by enzymatic esterification reaction of oleic acid and n-octanol. lipases from porcine pancreatic (ppl), mucor javanicus (mjl), candida sp. (cala), rhizomucor miehei (rml) and thermomyces lanuginosus (tll) were immobilized via interfacial activation on poly-methacrylate particles (pma) and tested as biocatalysts. their catalytic properties were determined in the hydrolysis of olive oil emulsion. among them, tll-pma was the biocatalyst that yielded the highest hydro ...201627477246
incorporation of palmitic acid or stearic acid into soybean oils using enzymatic interesterification.incorporations of nature fatty acids which were palmitic acid and stearic acid into the end positions of soybean oils were done using sn-1,3 specific immobilised lipase from rhizomucor miehei at different ratios in order to produce symmetrical triglycerides without changing the fatty acids at sn-2 position. the optimum ratio for the process was 25:75 w/w. there were 19.2% increase of sfa for p25 and 16% increase for s25 at the sn-1,3 positions. the research findings indicated that the structured ...201627477075
changes in volatile composition and sensory properties of iranian ultrafiltered white cheese as affected by blends of rhizomucor miehei protease or camel chymosin.the effect of using various combinations of rhizomucor miehei protease and camel chymosin (100:0, 75:25, 50:50, 25:75, and 0:100, respectively) on volatile composition and sensory scores in iranian ultrafiltered white cheese was studied during 90d of ripening. a solid-phase microextraction-gas chromatography-mass spectrometric method was used for determining the volatile compounds of the cheeses. forty compounds including esters (12), acids (6), ketones (9), alcohols (3), and miscellaneous compo ...201627423952
synthesis of geranyl propionate in a solvent-free medium using rhizomucor miehei lipase covalently immobilized on chitosan-graphene oxide beads.the chemical route of producing geranyl propionate involves the use of toxic chemicals, liberation of unwanted by-products as well as problematic separation process. in view of such problems, the use of rhizomucor miehei lipase (rml) covalently bound onto activated chitosan-graphene oxide (rml-cs/go) support is suggested. following analyses using fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy, and thermogravimetry, propertie ...201727341522
biotransformation of salpichrolides a, c, and g by three filamentous fungi.incubation of salpichrolide a (1) with rhizomucor miehei produced hydroxylation in rings b and c (c-7 and c-12) and led to c-5-c-6 epoxide opening, while incubation of salpichrolides c (2) and g (3) with r. miehei led to epoxide opening at the c-24-c-25 and c-5-c-6 positions, respectively. biotransformation of salpichrolide a (1) with cunninghamella elegans produced stereoselective hydroxylated, oxidized, and reduced derivatives in different positions of the a, b, and c rings and c-5-c-6 epoxide ...201627285201
reversible immobilization of lipases on heterofunctional octyl-amino agarose beads prevents enzyme desorption.two different heterofunctional octyl-amino supports have been prepared using ethylenediamine and hexylendiamine (oceda and ochda) and utilized to immobilize five lipases (lipases a (cala) and b (calb) from candida antarctica, lipases from thermomyces lanuginosus (tll), from rhizomucor miehei (rml) and from candida rugosa (crl) and the phospholipase lecitase ultra (lu). using ph 5 and 50 mm sodium acetate, the immobilizations proceeded via interfacial activation on the octyl layer, after some ion ...201627196882
[structure and activity of fungal lipases in bile salt solutions].the changes in structure and catalytic properties of fungal lipases (candida rugosa, rhizomucor miehei, mucor javanicus) were investigated in micellar solutions of bile salts that differ in hydrophilic-lypophilic balance and reaction medium properties. the methods of circular dichroism and tryptophan fluorescence were applied to estimate the changes in peptide structure within complexes with bile salt micelles. bile salts do not exert a significant influence on the structure of the enzymes under ...201627192825
evaluation of the catalytic specificity, biochemical properties, and milk clotting abilities of an aspartic peptidase from rhizomucor miehei.in this study, we detail the specificity of an aspartic peptidase from rhizomucor miehei and evaluate the effects of this peptidase on clotting milk using the peptide sequence of k-casein (abz-lsfmaiq-eddnp) and milk powder. molecular mass of the peptidase was estimated at 37 kda, and optimum activity was achieved at ph 5.5 and 55 °c. the peptidase was stable at ph values ranging from 3 to 5 and temperatures of up 45 °c for 60 min. dramatic reductions in proteolytic activity were observed with e ...201627165660
thermal destabilization of rhizomucor miehei rennet with aldehyde dextran sulfate: purification, bioconjugation and milk-clotting activities.high thermal stability of rhizomucor miehei rennet, which is a thermostable enzyme used in cheese production, causes undesired cases at elevated temperatures. this study aims to decrease the thermal stability of the r. miehei rennet at high temperatures. to achieve this goal, bioconjugates of r. miehei rennet with aldehyde derivative of dextran sulfate were synthesized in different molar ratios. physico-chemical properties of bioconjugates were characterized with particle size analyzer and gel p ...201627138725
intense pegylation of enzyme surfaces: relevant stabilizing effects.this chapter describes the physicochemical coating of the surface of immobilized enzymes with a dense layer of polyethylene glycol (peg) to improve enzyme stability. one hypothesis is that a dense, viscous, polar peg layer around the enzyme would enhance enzyme thermal stability, while still providing access to the active site. peg groups were attached by using aldehyde-dextran polymers, the dextran polymers are in turn attached to the enzyme surface that have been enriched with excess primary a ...201627112394
naringin lauroyl ester inhibits lipopolysaccharide-induced activation of nuclear factor κb signaling in macrophages.naringin (nar) has antioxidant and anti-inflammatory properties. it was recently reported that enzymatic modification of nar enhanced its functions. here, we acylated nar with fatty acids of different sizes (c2-c18) using immobilized lipase from rhizomucor miehei and investigated the anti-inflammatory effects of these molecules. treatment of murine macrophage raw264.7 cells with nar alkyl esters inhibited lipopolysaccharide (lps)-induced nitric oxide (no) production, with nar lauroyl ester (nar- ...201626967587
expression in pichia pastoris and characterization of rhizomucor miehei lipases containing a new propeptide region.a large number of propeptide regions from various proteins have been identified which function as intramolecular chaperones and assist the folding of the respective functional domains. the same polypeptide can fold into an altered conformation because of a mutated intramolecular chaperone and can maintain the "memory" of the folding process (new physicochemical properties). two new kinds of rhizomucor miehei lipase (rml) were constructed by replacing its propeptide region with that from either r ...201626923128
solvent-free lipase-catalyzed synthesis of diacylgycerols as low-calorie food ingredients.problems derived from obesity and overweight have recently promoted the development of fat substitutes and other low-calorie foods. on the one hand, fats with short- and medium-chain fatty acids are a source of quick energy, easily hydrolyzable and hardly stored as fat. furthermore, 1,3-diacylglycerols are not hydrolyzed to 2-monoacylglycerols in the gastrointestinal tract, reducing the formation of chylomicron and lowers the serum level of triacylglycerols by decreasing its resynthesis in the e ...201626904539
covalent binding of hyper-activated rhizomucor miehei lipase (rml) on hetero-functionalized siliceous supports.physical adsorption onto hydrophobic supports has proven to be an effective way to improve the activity of lipases. covalent binding, on the other hand, enhances the active lifetime of the immobilized biocatalysts. to combine the benefits of adsorption and covalent binding, immobilization of rml on new hetero-functional supports are reported. for this, chemical modification of silica and silica mesoporous nanoparticles was performed by the simultaneous use of two coupling linkers; octyltriethoxy ...201626812114
purification and characterization of a novel milk-clotting metalloproteinase from paenibacillus spp. bd3526.in this study, a milk-clotting enzyme (mce) isolated from paenibacillus spp. bd3526 was purified and characterized. the mce was purified 8.9-fold with a 10.11% recovery using ammonium sulfate precipitation and anion-exchange chromatography and the specific milk-clotting activity (mca) reached 6791.73 su/mg. the enzyme was characterized as a 35kda metalloproteinase, and the zymogen of which was encoded by a 1671 bp gene named zinc metalloproteinase precursor (zmp) with a predicted molecular weigh ...201626794311
biochemical characterization of a novel acidic exochitinase from rhizomucor miehei with antifungal activity.a novel chitinase gene (rmchi44) from rhizomucor miehei was cloned and expressed in escherichia coli as an intracellular soluble and active protein. the recombinant chitinase (rmchi44) was purified to homogeneity and biochemically characterized. the molecular mass of rmchi44 was estimated to be 44.6 kda on sds-page. rmchi44 displayed an acidic ph optimum of 4.5 and was stable within ph 4.5-9.0. the optimal temperature of rmchi44 was found to be 50 °c. the km values of rmchi44 for colloidal chiti ...201626709620
esolvent-free, enzyme-catalyzed biodiesel production from mango, neem, and shea oils via response surface methodology.mango, neem and shea kernels produce non-conventional oils whose potentials are not fully exploited. to give an added value to these oils, they were transesterified into biodiesel in a solvent-free system using immobilized enzyme lipozyme from mucor miehei. the doehlert experimental design was used to evaluate the methyl ester (me) yields as influenced by enzyme concentration-ec, temperature-t, added water content-awc, and reaction time-rt. biodiesel yields were quantified by (1)h nmr spectrosco ...201526698315
characteristics of esterified rice bran oil converted by enzymatic esterification.in the present study, esterified rice bran oil (erbo) was characterized using enzymatic esterification to improve stability, prevent acidification, enhance health-promoting biological activity and generate ω-3 pufa-rich rice bran oil (rbo). esterification reactions using rbo and ethanol were performed at 50°c under 200 bar with 3% lipozyme tl-im (thermomuces lanuginosa immobilized on silica gel) or rm-im (rhizomucor miehei immobilized on ion exchange resin) for 3 hr under supercritical co2. the ...201526688957
lipase-catalyzed synthesis of palmitanilide: kinetic model and antimicrobial activity study.enzymatic syntheses of fatty acid anilides are important owing to their wide range of industrial applications in detergents, shampoo, cosmetics, and surfactant formulations. the amidation reaction of mucor miehei lipase lipozyme im20 was investigated for direct amidation of triacylglycerol in organic solvents. the process parameters (reaction temperature, substrate molar ratio, enzyme amount) were optimized to achieve the highest yield of anilide. the maximum yield of palmitanilide (88.9%) was a ...201626672452
a unique gcn5-related glucosamine n-acetyltransferase region exist in the fungal multi-domain glycoside hydrolase family 3 β-n-acetylglucosaminidase.glycoside hydrolase (gh) family 3 β-n-acetylglucosaminidases widely exist in the filamentous fungi, which may play a key role in chitin metabolism of fungi. a multi-domain gh family 3 β-n-acetylglucosaminidase from rhizomucor miehei (rmnag), exhibiting a potential n-acetyltransferase region, has been recently reported to show great potential in industrial applications. in this study, the crystal structure of rmnag was determined at 2.80 å resolution. the three-dimensional structure of rmnag show ...201526669854
modulating the function of a β-1,3-glucanosyltransferase to that of an endo-β-1,3-glucanase by structure-based protein engineering.a glycoside hydrolase (gh) family 17 β-1,3-glucanosyltransferase (rmbgt17a) from rhizomucor miehei cau432 (cgmcc no. 4967) shared very low sequence homology (∼20 % identity) with that of other β-1,3-glucanases,despite their similar structural folds. structural comparison and sequence alignment between rmbgt17a and gh family 17 β-1,3-glucanases suggested important roles for three residues (tyr102, trp157, and glu158) located in the substrate-binding cleft of rmbgt17a in transglycosylation activit ...201626490553
crystal structure and characterization of a novel l-serine ammonia-lyase from rhizomucor miehei.l-serine ammonia-lyase, as a member of the β-family of pyridoxal-5'-phosphate (plp) dependent enzymes, catalyzes the conversion of l-serine (l-threonine) to pyruvate (α-ketobutyrate) and ammonia. the crystal structure of l-serine ammonia-lyase from rhizomucor miehei (rmsdh) was solved at 1.76 å resolution by x-ray diffraction method. the overall structure of rmsdh had the characteristic β-family plp dependent enzyme fold. it consisted of two distinct domains, both of which show the typical open ...201526367174
structure of product-bound smg1 lipase: active site gating implications.monoacylglycerol and diacylglycerol lipases are industrially interesting enzymes, due to the health benefits that arise from the consumption of diglycerides compared to the traditional triglyceride oils. most lipases possess an α-helix (lid) directly over the catalytic pocket which regulates the activity of the enzyme. generally, lipases exist in active and inactive conformations, depending on the positioning of this lid subdomain. however, lipase smg1, a monoacylglycerol and diacylglycerol spec ...201526365206
enhanced production of industrial enzymes in mucoromycotina fungi during solid-state fermentation of agricultural wastes/by-products.cellulolytic, lipolytic and proteolytic enzyme production of zygomycetes mucor corticolus, rhizomucor miehei, gilbertella persicaria and rhizopus niveus were investigated using agro-industrial wastes as substrates. solid-state cultures were carried out on untreated corn residues (stalk and leaf) as single substrate (ssf1) or corn residues and wheat bran in mixed fermentation (ssf2). rapid production of endoglucanase (cmcase) was observed with maximal activity reaching after about 48-h fermentati ...201526344030
macrocyclic trichothecenes from myrothecium roridum strain m10 with motility inhibitory and zoosporicidal activities against phytophthora nicotianae.the cytotoxicity of the extract obtained from myrothecium roridum m10 and a characteristic (1)h signal at δh ∼8 led to the assumption that verrucarin/roridin-type compounds were present. upscaling on rice medium led to the isolation of four new metabolites: verrucarins y (1) and z (6) (macrocyclic trichothecenes), bilain d (12) (a diketopiperazine derivative), and hamavellone c (14) (an unusual cyclopropyl diketone). in addition, nine known trichothecenes [verrucarin a (3), 16-hydroxyverrucarin ...201526320597
the first crystal structure of a glycoside hydrolase family 17 β-1,3-glucanosyltransferase displays a unique catalytic cleft.β-1,3-glucanosyltransferase (ec 2.4.1.-) plays an important role in the formation of branched glucans, as well as in cell-wall assembly and rearrangement in fungi and yeasts. the crystal structures of a novel glycoside hydrolase (gh) family 17 β-1,3-glucanosyltransferase from rhizomucor miehei (rmbgt17a) and the complexes of its active-site mutant (e189a) with two substrates were solved at resolutions of 1.30, 2.30 and 2.27 å, respectively. the overall structure of rmbgt17a had the characteristi ...201526249352
biotransformation of oleanolic and maslinic methyl esters by rhizomucor miehei cect 2749.the pentacyclic triterpenoids methyl oleanolate, methyl maslinate, methyl 3β-hydroxyolean-9(11),12-dien-28-oate, and methyl 2α,3β-dihydroxy-12β,13β-epoxyolean-28-oate were biotransformed by rhizomucor miehei cect 2749. microbial transformation of methyl oleanolate produced only a 7β,30-dihydroxylated metabolite with a conjugated 9(11),12-diene system in the c ring. biotransformation of the substrate with this 9(11),12-diene system gave the same 7β,30-dihydroxylated compound together with a 7β,15 ...201526232553
enzymatic kinetic resolution of racemic ibuprofen: past, present and future.this review is a journey concerning the investigations of the kinetic resolution of racemic ibuprofen for the last 20 years. the relevancy of the pharmacological uses of the s( + ) enantiomer along with its higher cost compared with racemic profen are the driving forces of a variety of scientific research studies addressing the enzymatic resolution of ibuprofen through enantiomeric esterification using lipases as biocatalysts. lipases of fungal sources such as candida rugosa, rhizomucor miehei a ...201626121932
structural insights into the substrate specificity of two esterases from the thermophilic rhizomucor miehei.two hormone-sensitive lipase (hsl) family esterases (rmesta and rmestb) from the thermophilic fungus rhizomucor miehei, exhibiting distinct substrate specificity, have been recently reported to show great potential in industrial applications. in this study, the crystal structures of rmesta and rmestb were determined at 2.15 å and 2.43 å resolutions, respectively. the structures of rmesta and rmestb showed two distinctive domains, a catalytic domain and a cap domain, with the classical α/β-hydrol ...201526108223
combined use of gap and aox1 promoters and optimization of culture conditions to enhance expression of rhizomucor miehei lipase.rhizo mucor miehei lipase (rml) is an industrially important enzyme, but its application is limited due to its high cost. in this study, a series of measures such as codon optimization, propeptide addition, combined use of gap and aox1 promoters, and optimization of culture conditions were employed to increase the expression of rml. three transformants of the constitutive-inducible combined pichia pastoris strains were generated by transforming the pgapzαa-rml vector into the ppic9k-rml/gs115 st ...201526013734
preparation of highly purified stearidonic acid from echium oil via an enzymatic method combined with preparative high performance liquid chromatography.stearidonic acid (sda), an n-3 polyunsaturated fatty acid (pufa), can be obtained from plant origin oils and it can be a good source of pufa for vegetarians. sda can be easily converted to longer pufa such as docosahexaenoic acid and eicosapentaenoic acid. highly purified stearidonic acid (sda) was prepared successfully from echium oil via an enzymatic method combined with preparative high performance liquid chromatography. in the 1(st) step, sda enrichment was accomplished using candida rugosa ...201525994555
lipase-catalyzed acidolysis of tripalmitin with capric acid in organic solvent medium: analysis of the effect of experimental conditions through factorial design and analysis of multiple responses.the acidolysis of tripalmitin with capric acid catalyzed by an immobilized form of a 1,3-positionally selective lipase (rhizomucor miehei) showed to be effective for the synthesis of structured lipids of the mll and mlm type. the effects that reaction parameters such as substrate molar ratio (n), biocatalyst load (e), and reaction temperature (t) have on selected responses variables (i.e. total conversion of tripalmitin, selectivity and yield of the desired structured lipid, hydrolysis yield, an ...201025919616
incorportation of ethyl esters of epa and dha in soybean lecithin using rhizomucor miehei lipase: effect of additives and solvent-free conditions.the transesterification of soybean lecithin with ethyl esters of polyunsaturated fatty acids (eicosapentaenoic acid (epa) and docosahexaenoic acid (dha)) using immobilized lipase from rhizomucor miehei was tested in the presence or absence of organic solvent (hexane) and additives (urea with ca(2+) or mg(2+)). the reaction was carried out at a water concentration of 4 % and ethyl ester to phospholipid mass ratio of 3:1. after 24 h of reaction without solvent or additive, fatty acid incorporation ...201525894950
high performance protein-coated microcrystals of rhizomucor miehei lipase: preparation and application for organic synthesis.the goal of obtaining enzyme forms with higher catalytic activity, greater stability, and improved reusability has been pursued for the last few decades. various novel biocatalyst designs have been created, and protein-coated microcrystals (pcmcs) are one of them. pcmc is an enzyme immobilization method based on simultaneous precipitation of protein and carrier, forming micron-sized enzyme-coated crystals. highly active rhizomucor miehei lipase (rml) pcmcs were prepared by immobilizing the prote ...201525800529
improved production of a recombinant rhizomucor miehei lipase expressed in pichia pastoris and its application for conversion of microalgae oil to biodiesel.we previously cloned a 1,3-specific lipase gene from the fungus rhizomucor miehei and expressed it in methylotrophic yeast pichia pastoris strain gs115. the enzyme produced (termed rml) was able to catalyze methanolysis of soybean oil and showed strong position specificity. however, the enzyme activity and amount of enzyme produced were not adequate for industrial application. our goal in the present study was to improve the enzyme properties of rml in order to apply it for the conversion of mic ...201425788976
lysophosphatidylcholine synthesis by lipase-catalyzed ethanolysis.lysophosphatidylcholine (lpc) is amphiphilic substance, and possesses excellent physiological functions. in this study, lpc was prepared through ethanolysis of phosphatidylcholine (pc) in n-hexane or solvent free media catalyzed by novozym 435 (from candida antarctica), lipozyme tlim (from thermomcyces lanuginosus) and lipozyme rmim (from rhizomucor miehei). the results showed that three immobilized lipases from candida antarctica, thermomcyces lanuginosus and rhizomucor miehei could catalyze et ...201525766935
high-level expression of a novel α-galactosidase gene from rhizomucor miehei in pichia pastoris and characterization of the recombinant enyzme.the second α-galactosidase gene (designated as rmgalb) was cloned from the thermophilic fungus rhizomucor miehei and expressed in pichia pastoris. the gene belonging to glycoside hydrolase (gh) family 36 has an open reading frame (orf) of 2241bp encoding 746 amino acids with two introns. the recombinant α-galactosidase (rmgalb) was secreted at high levels of 1953.9uml(-1) in high cell density fermentor, which is the highest yield obtained for a α-galactosidase. the purified enzyme as a tetramer ...201525712153
modification and simulation of rhizomucor miehei lipase: the influence of surficial electrostatic interaction on enantioselectivity.surface residues have a significant impact on the enantioselectivity of lipases. but the molecular basis of this has never been explained. in this work, transition state complexes of rhizomucor miehei lipase (rml) and (r)- or (s)-n-butyl 2-phenxypropinate were studied using molecular dynamics. according to comparison between b-factor of the two simulated complexes, the β 1-β 2 loop and α 2 helix were considered the enantioselectivity-determining domains of rml. interaction analysis of these doma ...201525650338
biodiesel production from microalgae oil catalyzed by a recombinant lipase.a recombinant rhizomucor miehei lipase was constructed and expressed in pichia pastoris. the target enzyme was termed lipase gh2 and it can be used as a free enzyme for catalytic conversion of microalgae oil mixed with methanol or ethanol for biodiesel production in an n-hexane solvent system. conversion rates of two major types of biodiesel, fatty acid methyl ester (fame) and fatty acid ethyl ester (faee), reached maximal values (>90%) after 24h. the process of fame production is generally more ...201525585254
biochemical characterization of a novel endo-1,5-α-l-arabinanase from rhizomucor miehei.a novel gene (designated as rmarase) encoding endo-1,5-α-l-arabinanase from a thermophilic fungus rhizomucor miehei was cloned and expressed in escherichia coli. the gene had an open reading frame (orf) of 930 base pairs (bp) encoding 309 amino acids. the amino acid sequence shared highest identity (56%) with a glycoside hydrolase (gh) family 43 endo-1,5-α-l-arabinase from bacillus subtilis and low identity (35%) with the endo-1,5-α-l-arabinase from aspergillus niger. the recombinant endo-1,5-α- ...201525582414
expression and characterization of a novel β-glucosidase, with transglycosylation and exo-β-1,3-glucanase activities, from rhizomucor miehei.a novel β-glucosidase gene, designated rmbglu3b, was cloned from the thermophilic fungus, rhizomucor miehei cau432. its 2196-bp open reading frame encoded 731 amino acids. its deduced amino-acid sequence showed highest identity (66%) with a glycoside hydrolase family 3 β-glucosidase from r. miehei nrrl5382. rmbglu3b was successfully expressed in escherichia coli. the recombinant enzyme was purified to homogeneity with 18.2-fold purification and 59% recovery yield. molecular masses of 76.5 kda, b ...201525577102
recent patents on microbial proteases for the dairy industry.this paper reviews the general characteristics of exo and endopeptidases of microbial origin currently used in the milk industry. it also includes recent patents developed either to potentiate the enzymatic activity or to improve the resulting milk derivatives. the main application of these proteases is in the cheese-making industry. although this industry preferentially uses animal rennets, and in particular genetically engineered chymosins, it also utilizes milk coagulants of microbial origin. ...201425564028
an acidic, thermostable exochitinase with β-n-acetylglucosaminidase activity from paenibacillus barengoltzii converting chitin to n-acetyl glucosamine.n-acetyl-β-d-glucosamine (glcnac) is widely used as a valuable pharmacological agent and a functional food additive. the traditional chemical process for glcnac production has some problems such as high production cost, low yield, and acidic pollution. hence, to identify a novel chitinase that is suitable for bioconversion of chitin to glcnac is of great value.201425550712
performance of structured lipids incorporating selected phenolic and ascorbic acids.conditions applied during frying require antioxidant which is stable at these conditions and provides protection for frying oil and fried food. novel structured lipids containing nutraceuticals and antioxidants were formed by enzymatic transesterification, exploring canola oil and naturally occurring antioxidants such as ascorbic and selected phenolic acids as substrates. lipozyme rm im lipase from rhizomucor miehei was used as biocatalyst. frying performance and oxidative stability of the final ...201525466089
high-level production of β-1,3-1,4-glucanase by rhizomucor miehei under solid-state fermentation and its potential application in the brewing industry.to improve the β-1,3-1,4-glucanase production by rhizomucor miehei under solid-state fermentation (ssf) for industrial application.201525393407
impact of different deacidification methods on quality characteristics and composition of olein and stearin in crude red palm oil.crude red palm oil of 8.7% free fatty acid content was deacidified using enzyme (lipase from rhizomucor miehei), solvent (ethanol) and chemical (aqueous sodium hydroxide) and its impact on chemical characteristics and composition were evaluated. deacidification of oil using enzyme showed nearly 100% product yield. the neutral lipid loss after ethanol and sodium hydroxide deacidification of the oil was 13.6% and 19.5% respectively. the enzyme deacidified oil has shown a higher value in unsaponifi ...201425391686
structural insights into the substrate specificity and transglycosylation activity of a fungal glycoside hydrolase family 5 β-mannosidase.β-mannosidases are exo-acting glycoside hydrolases (ghs) that catalyse the removal of the nonreducing end β-d-mannose from manno-oligosaccharides or mannoside-substituted molecules. they play important roles in fundamental biological processes and also have potential applications in various industries. in this study, the first fungal gh family 5 β-mannosidase (rmman5b) from rhizomucor miehei was functionally and structurally characterized. rmman5b exhibited a much higher activity against manno-o ...201425372687
lipozyme rm im-catalyzed acidolysis of cinnamomum camphora seed oil with oleic acid to produce human milk fat substitutes enriched in medium-chain fatty acids.in the present study, a human milk fat substitute (hmfs) enriched in medium-chain fatty acids (mcfas) was synthesized through acidolysis reaction from cinnamomum camphora seed oil (ccso) with oleic acid in a solvent-free system. a commercial immobilized lipase, lipozyme rm im, from rhizomucor miehei, was facilitated as a biocatalyst. effects of different reaction conditions, including substrate molar ratio, enzyme concentration, reaction temperature, and reaction time were investigated using res ...201425298236
enzymatic esterification of free fatty acids in vegetable oils utilizing different immobilized lipases.different immobilized lipases were screened for their ability to esterify free fatty acids (ffa) with monoacylglycerol (mag) as acyl-group acceptor. a lipase from rhizomucor miehei (lipozyme rmim) was the most suitable for lipase-catalyzed de-acidification-a promising alternative to conventional neutralization. a reduction of the ffa content to 0.6 % (w/w) was achieved by applying a substrate with an initial ffa-content of 6 % (w/w), the reaction at 50 °c for 22 h as well as the stepwise additio ...201525214229
production of olive oil enriched with medium chain fatty acids catalysed by commercial immobilised lipases.structured triacylglycerols, containing medium chain fatty acids, were produced by acidolysis of virgin olive oil with caprylic or capric acid, at a molar ratio of olive oil:fatty acid of 1:2, at 45°c for 24h, in solvent-free media or in n-hexane, catalysed by thermomyces lanuginosa (lipozyme tl im), rhizomucor miehei (lipozyme rm im) and candida antarctica (novozym 435) immobilised lipases. incorporations were always greater for capric than for caprylic acid. for both acids, higher incorporatio ...201125214088
lipase catalyzed transesterification of castor oil by straight chain higher alcohols.biolubricants from castor oil were produced enzymatically by transesterification with higher alcohols using a lipase mixture of immobilized mucor miehei (rmim) and immobilized candida antarctica lipase b (novozym 435) under low water conditions. the conversions were in the range of 80-95% under the optimized conditions.201525204793
immobilization of mucor miehei lipase onto macroporous aminated polyethersulfone membrane for enzymatic reactions.immobilization of enzymes is one of the most promising methods in enzyme performance enhancement, including stability, recovery, and reusability. however, investigation of suitable solid support in enzyme immobilization is still a scientific challenge. polyethersulfone (pes) and aminated pes (pes-nh2) were successfully synthesized as novel materials for immobilization. membranes with various pore sizes (from 10-600 nm) based on synthesized pes and pes-nh2 polymers were successfully fabricated to ...201224958172
biochemical characterization of the first fungal glycoside hydrolyase family 3 β-n-acetylglucosaminidase from rhizomucor miehei.a novel β-n-acetylglucosaminidase gene (rmnag) from rhizomucor miehei was cloned and expressed in escherichia coli. rmnag shares the highest identity of 37% with a putative β-n-acetylglucosaminidase from aspergillus clavatus. the recombinant enzyme was purified to homogeneity. the optimal ph and temperature of rmnag were ph 6.5 and 50 °c, respectively. it was stable in the ph range 6.0-8.0 and at temperatures below 45 °c. rmnag exhibited strict substrate specificity for p-nitrophenyl β-n-acetylg ...201424811866
gene cloning, functional expression and characterisation of a novel glycogen branching enzyme from rhizomucor miehei and its application in wheat breadmaking.a gene (rmgbe) encoding a glycogen branching enzyme from rhizomucor miehei was cloned into the pet28a (+) vector and expressed in escherichia coli, and biochemically analysed. rmgbe had an open reading frame of 2097bp encoding 698 amino acid residues. the purified enzyme was a monomer of 78.1kda. rmgbe was optimally active at 25°c and ph 7.5. it displayed excellent cold adaptation over a low temperature range of 10-30°c, retaining over 85% of its relative activity. rmgbe showed the highest speci ...201424767030
genome sequence and transcriptome analyses of the thermophilic zygomycete fungus rhizomucor miehei.the zygomycete fungi like rhizomucor miehei have been extensively exploited for the production of various enzymes. as a thermophilic fungus, r. miehei is capable of growing at temperatures that approach the upper limits for all eukaryotes. to date, over hundreds of fungal genomes are publicly available. however, zygomycetes have been rarely investigated both genetically and genomically.201424746234
lipase-catalyzed kinetic resolution of (±)-1-(2-furyl) ethanol in nonaqueous media.s-1-(2-furyl) ethanol serves as an important chiral building block for the preparation of various natural products, fine chemicals, and is widely used in the chemical and pharmaceutical industries. in this work, lipase-catalyzed kinetic resolution of (r/s)-1-(2-furyl) ethanol using different acyl donors was investigated. vinyl esters are good acyl donors vis-à-vis alkyl esters for kinetic resolution. among them, vinyl acetate was found to be the best acyl donor. different immobilized lipases suc ...201424733779
conversion of a rhizopus chinensis lipase into an esterase by lid swapping.in an effort to explore the feasibility of converting a lipase into an esterase by modifying the lid region, we designed and characterized two novel rhizopus chinensis lipase variants by lid swapping. the substrate specificity of an r. chinensis lipase was successfully modified toward water-soluble substrates, that is, turned into an esterase, by replacing the hydrophobic lid with a hydrophilic lid from ferulic acid esterase from aspergillus niger meanwhile, as a comparison, the lid of r. chinen ...201424670990
selective ethanolysis of sunflower oil with lipozyme rm im, an immobilized rhizomucor miehei lipase, to obtain a biodiesel-like biofuel, which avoids glycerol production through the monoglyceride formation.the obtaining of ecodiesel, a biofuel applicable to diesel engines which keeps the glycerin as monoglyceride (mg), was achieved through a selective ethanolysis process of sunflower oil, by application of lipozyme rm im, a rhizomucor miehei lipase immobilized on macroporous anion exchange resins. this biocatalyst that was already described in the synthesis of conventional biodiesel has also shown its efficiency in the present selective enzymatic process, after optimization of the influence of var ...201424594272
influence of culture conditions on the production of milk-clotting enzyme from rhizomucor.the ratio of milk-clotting activity to proteolytic activity (mc/pa) was used as an index to determine the quality of milk-clotting enzyme. solid-state fermentation on wheat bran for 5 days at room temperature gave optimal production for enzyme by rhizomucor miehei and r. pusillus. a ratio of wheat bran to moisture of 1:0.6 (w/v) gave best results. adding skim milk powder to the media of r. miehei did not improve the mc/pa ratio but 4% (w/w) of the powder did improve the ratio with r. pusillus. c ...199424421126
growth of three fungi on poultry fat or beef tallow.aspergillus niger, geotrichum candidum and mucor miehei, when grown on a medium containing beef tallow or poultry fat for 5 days at 28°c, in roux bottles, shake-flasks or fermenters, synthesized from 0.4 to 3.2 g lipids/i. the degree of fat utilization varied from 15 to 70%. the type of fat in the medium, the species of fungi and its cultivation method all influenced the fatty acid composition of fats remaining in the medium, as well as the intracellular lipids of the fungi.199324420293
in vivo and in vitro evaluation of octyl methoxycinnamate liposomes.solar radiation causes damage to human skin, and photoprotection is the main way to prevent these harmful effects. the development of sunscreen formulations containing nanosystems is of great interest in the pharmaceutical and cosmetic industries because of the many potential benefits. this study aimed to develop and evaluate an octyl methoxycinnamate (omc) liposomal nanosystem (liposome/omc) to obtain a sunscreen formulation with improved safety and efficacy by retaining omc for longer on the s ...201324376350
oxidation behavior of triacylglycerol containing conjugated linolenic acids in sn-1(3) or sn-2 position.the location of unsaturated fatty acid in triacylglycerols (tags) affects their oxidative stability. herein, we studied the effect of location of conjugated linolenic acids (clns) in tags on their oxidative stability. first, the tags containing clns at sn-1(3) and sn-2 positions, were enzymatically prepared via lipozyme rm-im (immobilized rhizomucor miehei lipase)-mediated acidolysis- and contained ca. 60% of clns at sn-1(3) or sn-2 position. the auto-oxidation test at 30°c in the dark showed ox ...201424371198
biochemical characterization of a novel l-asparaginase with low glutaminase activity from rhizomucor miehei and its application in food safety and leukemia treatment.a novel fungal gene encoding the rhizomucor miehei l-asparaginase (rmasnase) was cloned and expressed in escherichia coli. its deduced amino acid sequence shared only 57% identity with the amino acid sequences of other reported l-asparaginases. the purified l-asparaginase homodimer had a molecular mass of 133.7 kda, a high specific activity of 1,985 u/mg, and very low glutaminase activity. rmasnase was optimally active at ph 7.0 and 45°c and was stable at this temperature for 30 min. the final l ...201424362429
preparation of triacylglycerols rich in omega-3 fatty acids from sardine oil using a rhizomucor miehei lipase: focus in the epa/dha ratio.the increasing evidence on the differential biochemical effects of eicosapentaenoic acid (epa)/docosahexaenoic acid (dha) raises the need of n-3 highly unsaturated fatty acid concentrates with different amounts of these fatty acids. in the present work, physicochemical and enzymatic techniques were combined to obtain acylglycerols, mainly triacylglycerols (tag), rich in n-3 fatty acids. sardine oil was obtained by washing sardine (sardina pilchardus) mince with a nahco3 solution, hydrolyzed in a ...201424293255
biochemical characterization of a first fungal esterase from rhizomucor miehei showing high efficiency of ester synthesis.esterases with excellent merits suitable for commercial use in ester production field are still insufficient. the aim of this research is to advance our understanding by seeking for more unusual esterases and revealing their characterizations for ester synthesis.201324204998
properties and oxidative stabilities of enzymatically interesterified chicken fat and sunflower oil blend.chicken fat and sunflower oil 2:3 m/m blend was enzymatically interesterified at 60°c with and without microwaves assistance. as the catalyst a commercial preparation of the immobilized lipase from rhizomucor miehei (lipozyme rm im) containing 2% of water was used, and the catalyst load was 8% in each case. the starting mixture and the interesterified products were separated by column chromatography into pure triacylglycerols fraction (tag) and a non-triacylglycerol fraction, which contained fre ...201324200936
the structure of a glycoside hydrolase family 81 endo-β-1,3-glucanase.endo-β-1,3-glucanases catalyze the hydrolysis of β-1,3-glycosidic linkages in glucans. they are also responsible for rather diverse physiological functions such as carbon utilization, cell-wall organization and pathogen defence. glycoside hydrolase (gh) family 81 mainly consists of β-1,3-glucanases from fungi, higher plants and bacteria. a novel gh family 81 β-1,3-glucanase gene (rmlam81a) from rhizomucor miehei was expressed in escherichia coli. purified rmlam81a was crystallized and the struct ...201324100321
enhanced activity of rhizomucor miehei lipase by deglycosylation of its propeptide in pichia pastoris.many studies have demonstrated that the properties of enzymes expressed in eukaryotes can be affected by the position and extent of glycosylation on enzyme. in this study, two potential glycosylation sites (the 8th and the 58th asparagine) were identified and the effect of propeptide glycosylation on rhizomucor miehei lipase (rml) expressed in pichia pastoris was investigated. to better understand the effect of glycosylation on the activity of rml, three mutants (m1, generated by n8a; m2, genera ...201424068111
identification, isolation and optimization of antifungal metabolites from the streptomyces malachitofuscus ctf9.an indigenous streptomyces isolate ctf9, exhibiting promising antifungal activity against mucor miehei and candida albicans in pre-screening studies, was investigated by cultivation in a 50-l fermenter and by subsequent isolation, purification, and structure elucidation of the active metabolites. based on the morphological, biochemical, and physiological characterization, as well as the 16s rrna gene sequence, the isolate ctf9 was identified as streptomyces malachitofuscus. using a series of chr ...201124031671
one-pot lipase-catalyzed aldol reaction combination of in situ formed acetaldehyde.a facile tandem route to α,β-unsaturated aldehydes was developed by combining the two catalytic activities of the same enzyme in a one-pot strategy for the aldol reaction and in situ generation of acetaldehyde. lipase from mucor miehei was found to have conventional and promiscuous catalytic activities for the hydrolysis of vinyl acetate and aldol condensation with in situ formed acetaldehyde. the first reaction continuously provided material for the second reaction, which effectively reduced th ...201323975282
isocyanate-mediated covalent immobilization of mucor miehei lipase onto sba-15 for transesterification reaction.mucor miehei lipase (mm-l) covalently bind on a hexagonally ordered silica sba-15 (santa barbara amorphous), previously functionalized with isocyanate moieties, was examined as biocatalyst for transesterification of colza oil with methanol. the isocyanate-mesoporous silica (nco-sba-15) was obtained by condensation of silanol with triethoxysilane propyl isocyanate (tpi). the efficiency of the functionalization has been evidenced by infrared, (29)si and (13)c nmr spectroscopies. the substrate prov ...201323973672
oligomerization of 10,16-dihydroxyhexadecanoic acid and methyl 10,16-dihydroxyhexadecanoate catalyzed by lipases.the main monomer of tomato cuticle, 10,16-dihydroxyhexadecanoic acid (10,16-dhpa) and its methyl ester derivative (methyl-10,16-dihydroxyhexadecanote; methyl-10,16-dhhd), were used to study their oligomerization reactions catalyzed by five lipases: candida antarctica lipase b (cal-b), rhizomucor miehei lipase (rm), thermomyces lanuginosus lipase (tl), pseudomonas cepacia lipase (pcl) and porcine pancreatic lipase (ppl). for 10,16-dhpa, optimum yields were obtained at 60 °c using toluene and 2-me ...201323921794
synthesis of ascorbyl oleate by transesterification of olive oil with ascorbic acid in polar organic media catalyzed by immobilized lipases.the reaction of transesterification between oils (e.g., olive oil) and ascorbic acid in polar anhydrous media (e.g., tert-amyl alcohol) catalyzed by immobilized lipases for the preparation of natural liposoluble antioxidants (e.g., ascorbyl oleate) was studied. three commercial lipases were tested: candida antarctica b lipase (calb), thermomyces lanuginosus lipase (tll) and rhizomucor miehei lipase (rml). each lipase was immobilized by three different protocols: hydrophobic adsorption, anionic e ...201323891831
structure-guided modification of rhizomucor miehei lipase for production of structured lipids.to improve the performance of yeast surface-displayed rhizomucor miehei lipase (rml) in the production of human milk fat substitute (hmfs), we mutated amino acids in the lipase substrate-binding pocket based on protein hydrophobicity, to improve esterification activity. five mutants: asn87ile, asn87ile/asp91val, his108leu/lys109ile, asp256ile/his257leu, and his108leu/lys109ile/asp256ile/his257leu were obtained and their hydrolytic and esterification activities were assayed. using discovery studi ...201323844120
biotransformation of oleanolic and maslinic acids by rhizomucor miehei.microbial transformation of oleanolic acid by rhizomucor miehei produced three metabolites. a known compound, a 30-hydroxyl derivative (queretaroic acid), and two 7β,30- and 1β,30-dihydroxylated metabolites, respectively. the action of the same fungus (r. miehei) on maslinic acid produced an olean-11-en-28,13β-olide derivative, a metabolite hydroxylated at c-30, an 11-oxo derivative, and two metabolites with an 11α,12α-epoxy group, hydroxylated or not at c-30. their structures were elucidated by ...201323790643
incorporation of omega-3 polyunsaturated fatty acids into soybean lecithin: effect of amines and divalent cations on transesterification by lipases.the transesterification of soybean lecithin with methyl esters of epa and dha in an organic solvent (hexane) using various commercially available lipases was studied. lipases produced by candida antarctica, pseudomonas fluorescens, burkholderia cepacia, mucor miehei, thermomyces lanuginosus and rhizomucor miehei were compared, in the absence or presence of histidine, arginine, urea, ca²⁺, mg²⁺, or a combination of urea and divalent cations (additives at 5 % of the total lipid mass). transesterif ...201323749246
enzymatic interesterification of a lard and rapeseed oil equal-weight blend.a mixture of lard and rapeseed oil (1:1, wt/wt) was interesterified using immobilized lipases from rhizomucor miehei (lipozyme rm im) and candida antarctica (novozym 435) as catalysts. enzymatic interesterifications were carried out at 60°c for 8 h with lipozyme rm im or at 80°c for 4 h with novozym 435. the biocatalyst doses were kept constant (8 wt-%). the starting blend was quantitatively separated by column chromatography into pure triacylglycerol fraction (98.5%), and a nontriacylglycerol f ...201323535304
investigations on diffusion limitations of biocatalyzed reactions in amphiphilic polymer conetworks in organic solvents.the use of enzymes as biocatalysts in organic media is an important issue in modern white biotechnology. however, their low activity and stability in those media often limits their full-scale application. amphiphilic polymer conetworks (apcns) have been shown to greatly activate entrapped enzymes in organic solvents. since these nanostructured materials are not porous, the bioactivity of the conetworks is strongly limited by diffusion of substrate and product. the present manuscript describes tw ...201323532873
characterization of two novel family 12 xyloglucanases from the thermophilic rhizomucor miehei.two novel glycoside hydrolase (gh) family 12 xyloglucanase genes (designated rmxeg12a and rmxeg12b) were cloned from the thermophilic fungus rhizomucor miehei. both genes contained open reading frames of 729 bp encoding 242 amino acids. their deduced amino acid sequences shared 68% identity with each other and less than 60% with other xyloglucanases. the two genes, without the sequences for the signal peptides, were cloned and successfully expressed in escherichia coli as active xyloglucanases, ...201323463247
combined utilization of lipase-displaying pichia pastoris whole-cell biocatalysts to improve biodiesel production in co-solvent media.lipase-displaying whole cells appear to be efficient biocatalysts because of their low preparation costs and simple recycling procedure. the combined utilization of candida antarctica lipase b (calb) and rhizomucor miehei lipase (rml), separately displayed on pichia pastoris whole cells, to produce biodiesel in co-solvent media was investigated. a response surface methodology incorporating a d-optimal design was employed to obtain the optimum reaction conditions for methyl ester (me) synthesis. ...201223306117
gene cloning and enzymatic characterization of an alkali-tolerant endo-1,4-β-mannanase from rhizomucor miehei.an endo-1,4-β-mannanase gene (rmman5a) was cloned from the thermophilic fungus rhizomucor miehei for the first time and expressed in escherichia coli . the gene had an open reading frame of 1330 bp encoding 378 amino acids and contained four introns. it displayed the highest amino acid sequence identity (42%) with the endo-1,4-β-mannanases from glycoside hydrolase family 5. the purified enzyme was a monomer of 43 kda. rmman5a displayed maximum activity at 55 °c and an optimal ph of 7.0. it was t ...201323252695
in vitro interactions of amantadine hydrochloride, r-(-)-deprenyl hydrochloride and valproic acid sodium salt with antifungal agents against filamentous fungal species causing central nervous system infection.the mortality rates of fungal infections that affect the central nervous system are high in consequence of the absence of effective antifungal drugs with good penetration across the blood-brain barrier and the blood-cerebrospinal fluid barrier. in the present work in vitro antifungal activities of three good penetrating non-antifungal drugs (amantadine hydrochloride, r-(-)-deprenyl hydrochloride, valproic acid sodium salt) and their combinations with three antifungal agents (amphotericin b, itra ...201223134606
high yield of wax ester synthesized from cetyl alcohol and octanoic acid by lipozyme rmim and novozym 435.wax esters are long-chain esters that have been widely applied in premium lubricants, parting agents, antifoaming agents and cosmetics. in this study, the biocatalytic preparation of a specific wax ester, cetyl octanoate, is performed in n-hexane using two commercial immobilized lipases, i.e., lipozyme(®) rmim (rhizomucor miehei) and novozym(®) 435 (candida antarctica). response surface methodology (rsm) and 5-level-4-factor central composite rotatable design (ccrd) are employed to evaluate the ...201223109878
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