| synthesis of various kinds of esters by four microbial lipases. | ester synthesis by microbial lipases, using homogeneous enzyme preparations, were investigated. the amount of synthesized ester was estimated by alkalimetry, and products were identified by thin-layer chromatography and infrared spectroscopy. lipases from aspergillus niger, rhizopus delemar, geotrichum candidum and penicillium cyclopium synthesized esters from oleic acid and various primary alcohols. only geotrichum candidum lipase synthesized esters of secondary alcohols. esters of tertiary alc ... | 1979 | 508776 |
| glyceride synthesis by four kinds of microbial lipase. | apart from their usual mechanism of action, lipases from aspergillus niger and rhizopus delemar also catalyzed the synthesis of glycerides from oleic acid and glycerol. lipases from geotrichum candidum and penicillium cyclopium were inactivated by oleic acid, but were stable in the presence of casein, albumin or buffer of appropriate ph. lipases from aspergillus niger and rhizopus delemar synthesized glycerides from, not only fatty acid, but dibasic acids and aromatic acids, making ester bonds o ... | 1977 | 563245 |
| cloning, expression and characterization of a cdna encoding a lipase from rhizopus delemar. | a lambda gt11 cdna library was constructed in escherichia coli using poly(a)-selected mrna from the fungus, rhizopus (rp.) delemar. lipase-producing members of the library were identified by means of a phenotypic score wherein the release of fatty acids by lipase causes a characteristic color change in the growth medium. one such isolate contained a 1287-bp insert (lip cdna) which hybridizes to 1.25- to 1.35-kb mrna species from rp. delemar. the lipase produced in e. coli containing the lip cdna ... | 1991 | 1756969 |
| purification of plasmalogens using rhizopus delemar lipase and naja naja naja phospholipase a2. | bovine heart chogpl (choline glycerophospholipid) and bovine brain etngpl (ethanolamine glycerophospholipid) contain diacyl, alkenylacyl and alkylacyl analogs. purification of plasmalogens was achieved using r. delemar lipase and n. naja naja phospholipase a2 digestion. the r. delemar lipase hydrolyzes the acyl bond at the 1-position of 1,2-diacyl glycerophospholipids. the n. naja naja phospholipase a2 has greater activity with diacyl and alkylacyl than with alkenylacyl glycerophospholipids. the ... | 1990 | 2366631 |
| a study on the inhibition of aflatoxin b1 induced hepatocarcinogenesis by the rhizopus delemar. | the effect of rhizopus delemar on the carcinogenicity in rats of aflatoxin b1 was studied. the aflatoxin b1 was administered in free drinks to each male wistar rat at 126 micrograms per week such that a total dose of 3.40 mg was given over a period of 27 weeks. the culture abstract of rhizopus delemar was added simultaneously to a group of these rats by mixing the aflatoxin b1 solution. animals were killed separately during 18th, 30th, 38th and 52nd week. liver cell altered foci and neoplasms we ... | 1989 | 2518699 |
| [inhibition of aflatoxin b1-induced hepatocarcinogenesis by rhizopus delemar]. | | 1988 | 3150299 |
| interaction of rhizopus delemar lipase with 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane and structurally related pesticides: importance of 1:1 pesticide-lipase complexes. | | 1988 | 3378289 |
| inhibition of lipases by proteins: a binding study using dicaprin monolayers. | we previously reported that the inhibition of pancreatic and rhizopus delemar lipases by proteins is due to the protein associated with lipid and is not caused by direct protein-enzyme interaction in the aqueous phase [gargouri, y., piéroni, g., rivière, c., sugihara, a., sarda, l., & verger, r. (1985) j. biol. chem. 260, 2268-2273]. in this study, using radiolabeled lipases, serum albumin, and beta-lactoglobulin a, we investigated their respective binding with respect to lipolysis of dicaprin m ... | 1986 | 3707907 |
| modification of serum, pancreatic, and microbial lipase activities by phorbol diesters. | the influence of phorbol diesters on the in vitro hydrolysis of diacylglycerols was examined using enzymes from rat serum, porcine pancreas, and rhizopus delemar. two main phenomena were observed: 12-o-tetradecanoylphorbol-13-acetate (tpa), when added to the enzyme assay system, stimulated 2- to 3-fold the hydrolysis of [9,10-3h]dioleoylglycerol by serum lipase. the hydrolysis of dioleoylglycerol by either pancreatic or r. delemar lipase was, on the other hand, inhibited by tpa. a 50% inhibition ... | 1987 | 3791200 |
| effect of carbon and nitrogen sources on the chemical composition of lipids of rhizopus delemar. | soy bean extract with glucose or oleic acid in the growth medium of rhizopus delemar affected the production of higher values of biomass, total lipids and total glycerides than when ammonium nitrate was used as a source of nitrogen. the highest amounts of biomass (12.35 g/l) and total lipids (310 mg/g dry biomass) were attained in glucose-grown mycelia. the high proportions of total glycerides and unsaturated fatty acids in lipids of rhizopus delemar suggest the utilization of such lipid materia ... | 1986 | 3825190 |
| inhibition of lipases by proteins. a kinetic study with dicaprin monolayers. | we report further investigations on protein inhibition of pancreatic and microbial lipases carried out with the monolayer technique. when beta-lactoglobulin a, melittin, serum albumin, myoglobin, and a protein inhibiting lipase from soybean were preincubated with a dicaprin film at a surface pressure of 35 dynes/cm, no activity was detected with horse pancreatic or rhizopus delemar lipases. by contrast, rhizopus arrhizus and geotrichum candidum lipase activities were not impaired under the same ... | 1985 | 4038705 |
| roles of tryptophan residues on the rhizopus delemar lipase activity: chemical modification in a water-olive oil emulsion. | | 1973 | 4778940 |
| [some morphological and physiological properties of rhizopus delemar]. | | 1970 | 5497282 |
| pharmacological and toxicological studies on a starch diastatic enzyme "new sumyzyme" produced by rhizopus delemar var. multiplici-sporus. | | 1970 | 5535754 |
| a kinetic method for the determination of number-average molecular weight of linear high polymer by using an exo-enzyme. number-average molecular weights of various fractions of amylose determined by using gluc-amylase of rhizopus delemar. | | 1966 | 5970083 |
| inhibition of pancreatic and microbial lipases by proteins. | we have compared the effect of several proteins, including melittin, beta-lactoglobulin a, serum albumin, ovalbumin and myoglobin, on the hydrolysis of tributyrin and triolein by lipases from various origins. all proteins tested inactivate pancreatic lipase in absence of colipase and bile salt. inhibition is not significantly reversed by colipase in absence of bile salt except in systems containing tributyrin and melittin or triolein and beta-lactoglobulin a. in all other cases, activation of pa ... | 1984 | 6477949 |
| [growth and biotin synthesis of sporobolomyces pararoseus and rhizopus delemar under different substrate ratios]. | biotin synthesis by the yeast sporobolomyces pararoseus and the microscopic fungus rhizopus delemar was studied in batch cultures at different substrate ratios in the medium. the overall (exocellular + endocellular) biotin content in the yeast was 4.5-6.0 micrograms per 1 g of biomass on different media and did not depend on the growth phase. the content of biotin in the fungus was 7.5-9.0 micrograms per 1 g of biomass and depended neither on the growth phase nor on the quantitative ratio betwee ... | 1984 | 6541287 |
| [desthiobiotin transformation to biotin by the fungus rhizopus delemar]. | the object of this work was to study the transformation of desthiobiotin (dtb), a biotin precursor, to biotin by rhizopus delemar which can accumulate rather large quantities of biotin in the medium. both the growing and resting culture transform dtb at a high rate. biotin excretion by the resting culture rises by 100% when 25 micrograms/ml of dtb are added to the medium. the content of biotin within the cells remains unchanged. l-methionine, sodium sulfite and sodium sulfate are most effective ... | 1983 | 6664312 |
| [optimization of the medium for biotin biosynthesis by a culture of rhizopus delemar]. | the effect of nitrogen and carbon sources on the biotin biosynthesis by the fungal culture rhizopus delemar 1428 has been investigated. peptone and soy-bean flour have been shown to stimulate biotin synthesis. with the aid of mathematical planning methods the optimal composition of the nutrient medium and optimal concentrations of its components have been selected. the cultivation of rh. delemar 1428 on the thus developed medium leads to the accumulation of 600 micrograms/1 biotin in the culture ... | 1983 | 6878207 |
| increase in the activity of rhizopus delemar lipase on water-soluble esters by its binding with phosphatidylcholine. | rhizopus (rh.) delemar (atcc 34612) c-lipase was found to exhibit a slight activity towards water-soluble esters. the hydrolytic reaction of this lipase on alpha-naphthyl acetate was competitively inhibited by the presence of olive oil or tween 80. this finding showed that both substrates, insoluble triglyceride and water-soluble ester, were hydrolyzed at the same site on the enzyme. the activities on water-soluble esters (alpha-naphthyl acetate, beta-naphthyl acetate, methyl acetylsalicylate an ... | 1983 | 6885742 |
| [biotin formation by the fungus rhizopus delemar]. | the capability of 26 collection micromycete strains to synthesize biotin and transform destiobiotin was investigated. destiobiotin stimulated the biotin formation by the strains of the aspergillus genus (except a. sclerotiorum synthesizing vitamin traces), the fusarium genus, the rhizopus genus (except rh. nigricans), as well as thighemella hyalospora and sporotrichum sulfurescens. among the strains tested rhizopus delemar 1428 synthesized maximum quantities of biotin (over 300 micrograms/1). th ... | 1982 | 7145874 |
| preparation of thioester substrates and development of continuous spectrophotometric assays for phospholipase a1 and monoacylglycerol lipase. | current assays of phospholipase a1 (ec 3.1.1.32) and monoacylglycerol lipase (ec 3.1.1.23) activities in tissues are discontinuous, laborious, and expensive. some spectrophotometric substrates were synthesized to alleviate this problem. thioester analogs of phosphatidylcholine and phosphatidylethanolamine. rac-1,2-s,o-didecanoyl-3-phosphocholine-1-mercapto-2,3-propanediol and rac-1,2-s,o-didecanoyl-3-phosphoethanolamine-1-mercapto-2,3-propanediol, were synthesized from the diacylglycerol analog, ... | 1981 | 7240974 |
| reversibility of the modification of rhizopus delemar lipases by phosphatidylcholine. | rhizopus (rh.) delemar (atcc 34612) lipase is modified by its binding with phosphatidylcholine (pc); such binding enhances the lipoprotein lipase (lpl) activity, shifts the isoelectric point (pi) to the acidic side and decreases its alpha-helical content ((1980) j. biochem. 88, 533-538). the results of density gradient ultracentrifugation proved that pc binding to lipase molecule was depleted by the treatment of pc-bound lipase with 0.3% triton x-100 and 0.1 m nacl. by this treatment, lpl activi ... | 1981 | 7287646 |
| modification of rhizopus delemar lipase by its binding with phospholipids. | rhizopus delemar (atcc 34612) lipase was modified by phospholipid (pl)-treatment so as to enhance its activity on lipoprotein. in order to detect change in lipase conformation in the modified state, a preliminary experiment was performed to remove pl from the pl-treated lipase solution which included pl nonessential to enhancement of lipoprotein lipase (lpl) activity. it was found that treatment with a mixture of isopropyl ether: n-butanol (3 : 1) was suitable for this purpose because of the sta ... | 1980 | 7419510 |
| cloning of the rhizopus niveus pyr4 gene and its use for the transformation of rhizopus delemar. | we have cloned a pyr4 gene encoding orotidine-5'-monophosphate decarboxylase of the filamentous fungus rhizopus niveus. the pyr4 gene of r. nivens has an open reading frame composed of 265 amino-acid residues and has two putative introns. we have also isolated a pyr4 mutant of rhizopus delemar from 5-fluoroorotic acid-resistant mutants and transformed it with the pyr4 gene of r. niveus as a selectable marker. introduced dna was integrated into the chromosome in a multiple tandem array. the mitot ... | 1995 | 7586035 |
| cloning and nucleotide sequence of cdna encoding a lipase from fusarium heterosporum. | fusarium heterosporum produces a solvent-tolerant lipase. a 1.3-kbp lipase cdna was isolated from the cdna library by colony hybridization with an oligonucleotide probe corresponding to the n-terminal amino acid sequence. nucleotide sequence analysis showed an open reading frame of 999 bp, and the deduced amino acid sequence contained the n-terminal sequence determined by edman degradation and the consensus pentapeptide (-gly-x-ser-x-gly-), which is conserved in lipase, esterase, and serine prot ... | 1994 | 7852271 |
| conformational lability of lipases observed in the absence of an oil-water interface: crystallographic studies of enzymes from the fungi humicola lanuginosa and rhizopus delemar. | considerable controversy exists regarding the exact nature of the molecular mechanism of interfacial activation, a process by which most lipases achieve maximum catalytic activity upon adsorption to an oil water interface. x-ray crystallographic studies show that lipases contain buried active centers and that displacements of entire secondary structure elements, or "lids," take place when the enzymes assume active conformations [derewenda, u., a. m. brzozowski, d. m. lawson, and z. s. derewenda. ... | 1994 | 8014587 |
| current progress in crystallographic studies of new lipases from filamentous fungi. | lipases from filamentous fungi have been studied extensively over many years. they exhibit properties attractive for industrial applications, e.g. in laundry detergents, tanning and paper industries and stereospecific organic synthesis. enzymes from the fungi rhizomucor miehei and geotrichum candidum have been among the first neutral lipases to be characterized structurally by x-ray diffraction methods. in this paper we report a preliminary account of crystallographic studies of three other fung ... | 1994 | 8029211 |
| alteration of chain length selectivity of a rhizopus delemar lipase through site-directed mutagenesis. | the coding sequences of the rhizopus delemar lipase and prolipase were altered by oligonucleotide-directed mutagenesis to introduce amino acid substitutions. the resulting mutant enzymes, synthesized by the bacterial host escherichia coli bl21 (de3), were tested for their ability to hydrolyze the triglycerides triolein (to), tricaprylin (tc) and tributyrin (tb). mutagenesis and lipase gene expression were carried out using plasmid vectors derived from previously described recombinant plasmids [j ... | 1994 | 8090057 |
| crystallization and preliminary crystallographic studies of the precursor and mature forms of a neutral lipase from the fungus rhizopus delemar. | a neutral lipase from the filamentous fungus rhizopus delemar has been crystallized in both its proenzyme and mature forms. although the latter crystallizes readily and produces a variety of crystal forms, only one was found to be suitable for x-ray studies. it is monoclinic (c2, a = 92.8 a, b = 128.9 a, c = 78.3 a, beta = 135.8) with two molecules in the asymmetric unit related by a noncrystallographic diad. the prolipase crystals are orthorhombic (p2(1)2(1)2(1), with a = 79.8 a, b = 115.2 a, c ... | 1994 | 8202471 |
| molecular characterization of an extracellular acid-resistant lipase produced by rhizopus javanicus. | an extracellular lipase (triacylglycerol acylhydrolase ec 3.1.1.3), produced by the fungus rhizopus javanicus was purified to homogeneity using an expeditious two-step isolation method. the enzyme, with a molecular mass of 36 kda and a specific activity of 9260 microequivalent of fatty acid released per minute and mg under standard conditions, consists of three isoforms with isoelectric points of 7.8, 7.7, and 7.1, respectively. the purified lipase was digested using chemical and enzymatical pro ... | 1993 | 8329142 |
| overexpression of a rhizopus delemar lipase gene in escherichia coli. | a cloned complementary deoxyribonucleic acid encoding the precursor polypeptide of an extracellular lipase from the fungus rhizopus delemar was altered by site-directed mutagenesis to generate deoxyribonucleic acid fragments that specifically code for the polypeptides of the proenzyme and the mature form of the lipase. attempts to produce these polypeptides in enzymatically active form in escherichia coli revealed toxic effects toward the host. therefore the polypeptides were expressed as inacti ... | 1993 | 8441342 |
| contribution of cutinase serine 42 side chain to the stabilization of the oxyanion transition state. | cutinase from the fungus fusarium solani pisi is a lipolytic enzyme able to hydrolyze both aggregated and soluble substrates. it therefore provides a powerful tool for probing the mechanisms underlying lipid hydrolysis. lipolytic enzymes have a catalytic machinery similar to those present in serine proteinases. it is characterized by the triad ser, his, and asp (glu) residues, by an oxyanion binding site that stabilizes the transition state via hydrogen bonds with two main chain amide groups, an ... | 1996 | 8555209 |
| the consequences of engineering an extra disulfide bond in the penicillium camembertii mono- and diglyceride specific lipase. | the extracellular lipase from penicillium camembertii has unique substrate specificity restricted to mono- and diglycerides. the enzyme is a member of a homologous family of lipases from filamentous fungi. four of these proteins, from the fungi rhizomucor miehei, humicola lanuginosa, rhizopus delemar and p. camembertii, have had their structures elucidated by x-ray crystallography. in spite of pronounced sequence similarities the enzymes exhibit significant differences. for example, the thermost ... | 1996 | 8888145 |
| the use of rational mutagenesis to modify the chain length specificity of a rhizopus delemar lipase. | | 1996 | 8958082 |
| altered acyl chain length specificity of rhizopus delemar lipase through mutagenesis and molecular modeling. | the acyl binding site of rhizopus delemar prolipase and mature lipase was altered through site-directed mutagenesis to improve lipase specificity for short- or medium-chain length fatty acids. computer-generated structural models of r. delemar lipase were used in mutant protein design and in the interpretation of the catalytic properties of the resulting recombinant enzymes. molecular dynamics simulations of the double mutant, val209trp + phe112trp, predicted that the introduction of trp112 and ... | 1997 | 9075201 |
| effect of water extracts of rhizopus delemar on the stimulus coupled responses of neutrophils and their modulation by various protein kinase inhibitors. | human peripheral blood polymorphonuclear leukocytes were preincubated with water extracts from rhizopus delemar. the water extracts significantly inhibited arachidonic acid induced superoxide generation, whereas enhanced superoxide generation induced by phorbol 12-myristate 13-acetate but not those induced by n-formyl-methionyl-leucyl-phenylalanine. superoxide generation induced by water extracts was inhibited by staurosporine, an inhibitor of protein kinase c, and was enhanced by genistein, an ... | 1999 | 10340437 |
| synthesis and enzymatic degradation of optically active depsipeptide copolymers. | this paper describes the synthesis and biodegradation of copolymers of cyclic depsipeptide with epsilon-caprolactone (cl) or lactide (la). optically active cyclic depsipeptides, 3,6-dimethyl-2,5-morpholinediones (dmos), were prepared by the reaction of an amino acid (d-, l-, or dl-alanine) with a hydroxy acid derivative (dl-2-bromopropionyl bromide). these isomers are abbreviated as d-dmo, l-dmo and dl-dmo respectively, according to the names of alanine isomers. then, we have prepared the copoly ... | 1999 | 10385224 |
| non-thiazolidinedione antihyperglycaemic agents. part 3: the effects of stereochemistry on the potency of alpha-methoxy-beta-phenylpropanoic acids. | rhizopus delemar lipase catalysed ester hydrolysis of the alpha-methoxy-beta-phenylpropanoate 1 affords the (r)-(+) and (s)-(-) isomers in > 84% enantiomeric excess. absolute stereochemistry was determined by a single crystal x-ray analysis of a related synthetic analogue. the activity of these two enantiomers on glucose transport in vitro and as anti-diabetic agents in vivo is reported and their unexpected equivalence attributed to an enzyme-mediated stereospecific isomerisation of the (r)-(+) ... | 1999 | 10400335 |
| highly selective synthesis of 1,3-oleoyl-2-palmitoylglycerol by lipase catalysis. | 1,3-oleoyl-2-palmitoylglycerol (opo), an important structured triglyceride in infant nutrition, was synthesized by a two-step process in high yields and purity using sn1,3-regiospecific lipases. in the first step, tripalmitin (tp) was subjected to an alcoholysis reaction in an organic solvent catalyzed by sn1,3-regiospecific lipases yielding the corresponding 2-monopalmitin (2-mp). the 2-mp was isolated in up to 85% yield and >95% purity by crystallization and esterified in the second step with ... | 1999 | 10417216 |
| cloning and expression analysis of nhl1, a gene encoding an extracellular lipase from the fungal pea pathogen nectria haematococca mp vi (fusarium solani f. sp. pisi) that is expressed in planta. | the filamentous fungus nectria haematococca (anamorph fusarium solani f. sp. pisi) resides in soil, and attacks pea seedlings in the area of the underground epicotyl and upper tap root, causing foot rot disease. we detected lipase activity during in vitro growth of n. haematococca. subsequently, a lipase gene was cloned and functionally characterised by heterologous expression in saccharomyces cerevisiae. the full-length cdna of 1152 bp was cloned using a 3' race-pcr approach coupled with cdna l ... | 2001 | 11361331 |
| kinetic studies of rhizopus oryzae lipase using monomolecular film technique. | rhizopus oryzae lipase (rol) was found to be a true lipase. this enzyme presents the interfacial activation phenomenon. the n-terminal amino acid sequence of rol was compared to those of rhizopus lipases. purified rol possesses the same n-terminal sequence as the mature rhizopus niveus lipase (rnl). this sequence was found in the last 28 amino acids of the propeptide sequence derived from the cdna of rhizopus delemar lipase (rdl). using the baro-stat method, we have measured the hydrolysis rate ... | 2001 | 11506890 |
| chemoenzymatic synthesis of antiviral carbocyclic nucleosides: asymmetric hydrolysis of meso-3,5-bis(acetoxymethyl)cyclopentenes using rhizopusdelemar lipase. | 7-substituted norbornadienes were stereoselectively converted into the meso-3,5-bis(acetoxymethyl)cyclopentenes by a three-step sequence of ozonolysis, reduction, and acetylation. rhizopus delemar lipase (rdl)-catalyzed asymmetric hydrolysis of meso-3,5-bis(acetoxymethyl)cyclopentenes afforded the monoalcohols of high enantiomeric purities (>95% ee) in good yields (64-95%). the obtained monoalcohols 11 and 14 could be applied for the synthesis of antiviral carbocyclic nucleosides (-)-carbovir an ... | 1996 | 11667592 |
| adsorption properties and activities of lipase on a gold substrate modified by self-assembled monolayers. | the adsorption properties, amount and specific activity of lipase d from rhizopus delemar were investigated by employing a gold substrate modified with seven kinds of thiol monolayer. quartz crystal microbalance measurements revealed that the amount of the enzyme adsorbed to the hydrophobic monolayers (e.g. benzenethiol) was much higher than that to the hydrophilic monolayers (e.g. 3-mercaptopropanoic acid). in contrast, lipase d adsorbed to the hydrophilic, 2-amino-1-ethanethiol monolayer showe ... | 2001 | 11791710 |
| removal of heavy metals from aqueous solution using rhizopus delemar mycelia in free and polyurethane-bound form. | this study assesses the ability of mycelia of rhizopus delemar (both free and immobilized on polyurethane foam) to remove heavy metals from single-ion solutions as well as from a mixture of them. all experiments were conducted using 0.5-5 mm solutions of cuso4 x 5h2o, cocl2-6h2o and feso4 7h2o. mycelia immobilized on polyurethane foam cells showed some times increase in uptake compared with that of free cells. metal ions accumulation from a mixed solution was decreased slightly for cobalt and ir ... | 2002 | 12240988 |
| interesterification activity of rhizopus delemar lipase in phospholipid microemulsions. | the interesterification of olive oil with palmitic acid catalyzed by rhizopus delemar lipase was investigated in phospholipid microemulsion systems. soybean lecithin was used as the amphiphilic component. the maximal reaction rate was obtained at a buffer ph of 5.5-6.0. the reaction rate was also dependent on the w(l) (= [h2o]/[lecithin]) value and attained a maximum at w(l)=5. the reaction rate reached a maximum at a palmitic acid concentration of 350 mm. the molar fraction of the interesterifi ... | 2004 | 15542321 |
| an improved method for sn-2 position analysis of triacylglycerols in edible oils and fats based on immobilised lipase d (rhizopus delemar). | the use of lipase d (rhizopus delemar) immobilised on microporous polypropylene as a replacement for the standard pancreatic lipases used in the stereospecific sn-2 position analysis of triacylglycerols from edible oils and fats is studied. excellent hydrolysis characteristics are obtained in hexane/methanol solvents at reaction temperatures up to 60 degrees c with hydrolysis times of only 10-20 min. the favourable conditions for the hydrolysis reaction allow fats with higher melting points to b ... | 2006 | 16368101 |
| biodegradable network elastomeric polyesters from multifunctional aliphatic carboxylic acids and poly(epsilon-caprolactone) diols. | biodegradable elastomeric network polyesters were prepared from multifunctional aliphatic carboxylic acids such as tricarballylic acid (yt) or meso-1,2,3,4-butanetetracarboxylic acid (xb) and poly(epsilon-caprolactone) (pcl) diols with molecular weights of 530, 1,250 and 2,000 g.mol-1. prepolymers prepared by a melt polycondensation were cast from dmf solution and postpolymerized at 280 degrees c for various periods of times to form a network. the resultant films were transparent, flexible and i ... | 2006 | 16676379 |
| biochemical and molecular characterization of a lipase produced by rhizopus oryzae. | a novel strain of rhizopus oryzae wpg secretes a noninduced lipase (rolw) in the culture medium; purified rolw is a protein of 29 kda, the 45 n-terminal amino acid residues were sequenced, this sequence is very homologous to rhizopus delemar lipase (rdl), rhizopus niveus lipase (rnl) and r. oryzae lipase (rol29) sequences; the cloning and sequencing of the part of the gene encoding the mature rolw, shows two nucleotides differences with rdl, rnl and rol29 sequences corresponding to the change of ... | 2006 | 16842350 |
| synthesis, cocrystallization, and enzymatic degradation of novel poly(butylene-co-propylene succinate) copolymers. | a series of poly(butylene-co-propylene succinate) (pbpsu) random copolyesters were synthesized and characterized using 1hnmr spectroscopy and viscometry. tensile properties decreased with increasing propylene succinate (psu) content. cocrystallization and multiple melting behaviors were investigated. the copolymers showed a eutectic behavior. the minimum melting point corresponded to 75 mol % psu. wide-angle x-ray diffraction (waxd) patterns showed that the copolymers with up to 60 mol % psu uni ... | 2007 | 17655353 |
| rhizopus delemar is the proper name for rhizopus oryzae fumaric-malic acid producers. | the zygomycete rhizopus oryzae currently is identified by sporangiophore morphology and growth temperature, but heterogeneity of the species has been reported. we examined the suitability of organic acid production as an effective taxonomic character for reclassification of the species. strains were divided into two groups, la (lactic acid producer) and fma (fumaric-malic acid producers) according to organic acid production. these grouping were confirmed as phylogenetically distinct because anal ... | 2007 | 18268905 |
| immobilization of enzyme onto poly(ethylene-vinyl alcohol) membrane. | invertase was ionically bound to the poly(ethylene-vinyl alcohol) membrane surface modified with two aminoacetals with different molecular length, 2-dimethyl-aminoacetoaldehyde dimethylacetal (aaa) and 3-(n, n-dimethylamino-n-propanediamine) propionaldehyde dimethylacetal (apa). immobilization conditions were determined with respect to enzyme concentration in solution, ph value, ionic strength in immobilization solution, and immobilization time. various properties of immobilized invertase were e ... | 1986 | 18555315 |
| esterification reactions of lipase in reverse micelles. | the activities of lipase from candida cylindracea and rhizopus delemar have been investigated in water/aot/iso-octane reverse micellar media through the use of two esterification reactions: fatty acid-alcohol esterification and glyceride synthesis. such media promotes the occurrence of these two lipase-catalyzed reactions due to its low water content. the effect of various parameters on the activity of lipase from c. cylindracea in reverse micelles was determined and compared to results where al ... | 1990 | 18592580 |
| formation of polyol-fatty acid esters by lipases in reverse micellar media. | the synthesis of polyol-fatty acid esters has strong implications in such industries as foods, cosmetics, and polymers. we have investigated these esterification reactions employing the polyols ethylene glycol, 2-monoglyceride, and sugars and their derivatives with the biocatalyst lipase in water/aot/isooctane reverse micellar media. for the first reaction, 50-60% conversion was achieved and product selectivity toward the monoester over the diester shown possible by employing lipase from rhizopu ... | 1992 | 18601051 |
| esterification reactions catalyzed by lipases in microemulsions: the role of enzyme localization in relation to its selectivity. | the activity of lipases from rhizopus delemar, rhizopus arrhizus, and penicillium simplicissimum entrapped in microemulsions formulated by bis-(2-ethylhexyl)sulfo-succinate sodium salt (aot) in isooctane has been studied in esterification reactions of various aliphatic alcohols with fatty acids. the effect of the nature of the fatty acids (chain length) and of the alcohols (primary, secondary, or tertiary; chain length; cyclic structures) on the lipase activities was investigated in relation to ... | 1993 | 18609653 |
| correlation between chemical and solid-state structures and enzymatic hydrolysis in novel biodegradable polyesters. the case of poly(propylene alkanedicarboxylate)s. | a series of seven fast-biodegrading aliphatic polyesters were prepared from 1,3-propanediol and aliphatic diacids with increasing number of methylene units (x). melting points decreased from ppsu to ppad and then increased again to ppaz and ppseb. crystallization rates and thermal stability increased steadily with increasing x. glass transition temperatures decreased steadily to pppim and subsequently increased. enzymatic degradation of the polymers in the presence of a mixture of rhizopus delem ... | 2008 | 18615455 |
| molecular characterization of the relationships among amylomyces rouxii, rhizopus oryzae, and rhizopus delemar. | twenty-one strains of amylomyces rouxii isolated from starters of asian fermented foods were divided into two groups, lactic acid (la) and fumaric and malic acid (fma) producers, by organic acid productivity in liquid culture. phylogenetic analysis based on the ldhb gene, ribosomal rna encoding dna (rdna) internal transcribed spacer (its) sequence, and genome-wide amplified fragment length polymorphism (aflp) revealed that a. rouxii was grouped into two major clusters as to organic acid accumula ... | 2009 | 19352027 |
| a study on the inhibition kinetics of bioaccumulation of cu(ii) and ni(ii) ions using rhizopus delemar. | the microbial growth and simultaneous bioaccumulation of cu(ii) and ni(ii) ions during the growth of rhizopus delemar in molasses medium was investigated in a batch system. the level of cu(ii) and ni(ii) bioaccumulation and microbial growth was dependent on ph, molasses sucrose concentration and initial cu(ii) and ni(ii) ion concentrations. an increase in initial total metal ion concentration inhibited both the growth rate of fungus and the bioaccumulation capacity. lineweaver-burk plot of monod ... | 2009 | 19362774 |
| multilocus microsatellite typing for rhizopus oryzae. | rhizopus oryzae is the most frequent causative agent of zygomycosis. although zygomycosis causes considerable morbidity and mortality in immunocompromised patients, the epidemiology of the disease is not well studied and no standard molecular typing method has been described for any of the causative agents. here we describe a multilocus microsatellite typing (mlmt) method for r. oryzae. r. oryzae genome sequences were downloaded from the fungal genome initiative database (broad institute). the i ... | 2010 | 20724504 |
| acid phosphatase production by rhizopus delemar: a role played in the ni(ii) bioaccumulation process. | the microbial growth and activity of acid phosphatase enzyme during the growth of rhizopus delemar in the presence or absence of ni(ii) ions were investigated. an increase in initial ni(ii) ion concentration inhibited both growth rate of r. delemar and acid phosphatase activity. the maximum-intrinsic specific growth rate (μ(m)) and monod constant (k(s)) of microorganism in ni(ii)-free medium were found as 0.0649 h(-1) and 1.8928 g/l, respectively. the inhibition of ni(ii) ions on growth rate of ... | 2010 | 20846788 |
| optimization of fumaric acid production by rhizopus delemar based on the morphology formation. | the effects of temperature, agitation rate and medium composition, including concentrations of glucose, soybean peptone, and inorganic ions, on pellet formation and pellet diameter of rhizopus delemar (rhizopus oryzae) nrrl1526 during pre-culture were studied. inorganic ions and soybean peptone had negative and positive effects on pellet formation, respectively. the initial glucose and soybean peptone concentrations directly affected pellet diameter. within a certain range, pellet diameter decre ... | 2011 | 21880482 |
| molecular characterization and in vitro antifungal susceptibility of 80 clinical isolates of mucormycetes in delhi, india. | mucormycosis is a highly aggressive disease which is usually fatal in immunocompromised patients. the species of mucormycetes show significant differences in susceptibility to amphotericin b, azoles and terbinafine. the precise species level identification for this fungal group could be achieved by internal transcribed-spacer (its) region sequencing. herein, we present the largest series of antifungal susceptibility data of molecularly characterised isolates of mucormycetes reported so far from ... | 2014 | 25250768 |
| evaluation of pyrolysis oil as carbon source for fungal fermentation. | pyrolysis oil, a complex mixture of several organic compounds, produced during flash pyrolysis of organic lignocellulosic material was evaluated for its suitability as alternative carbon source for fungal growth and fermentation processes. therefore several fungi from all phyla were screened for their tolerance toward pyrolysis oil. additionally aspergillus oryzae and rhizopus delemar, both established organic acid producers, were chosen as model organisms to investigate the suitability of pyrol ... | 2016 | 28066378 |
| metagenomics analysis of microbial communities associated with a traditional rice wine starter culture (xaj-pitha) of assam, india. | this is the first report on the microbial diversity of xaj-pitha, a rice wine fermentation starter culture through a metagenomics approach involving illumine-based whole genome shotgun (wgs) sequencing method. metagenomic dna was extracted from rice wine starter culture concocted by ahom community of assam and analyzed using a miseq(®) system. a total of 2,78,231 contigs, with an average read length of 640.13 bp, were obtained. data obtained from the use of several taxonomic profiling tools were ... | 2016 | 28330225 |
| syncephalastrum racemosum amine oxidase with high catalytic efficiency toward ethanolamine and its application in ethanolamine determination. | our screening study yielded a copper amine oxidase (sraox) from syncephalastrum racemosum, which showed much higher affinity and catalytic efficiency toward ethanolamine (ea) than any other amine oxidase (aox). following purification of the enzyme to electrophoretic homogeneity from a cell-free extract, the maximum activity toward ea was detected at ph 7.2-7.5 and 45 °c. the sraox complementary dna (cdna) was composed of a 2052-bp open reading frame encoding a 683-amino acid protein with a molec ... | 2016 | 26691518 |
| monotherapy or combination therapy of isavuconazole and micafungin for treating murine mucormycosis. | previously we demonstrated the benefit of isavuconazole in treating murine mucormycosis due to rhizopus. we wanted to determine the efficacy of isavuconazole in treating murine mucormycosis caused by mucor, the second most common cause of the disease. furthermore, because we previously determined that rhizopus possesses the target enzyme for echinocandins and micafungin has activity against murine mucormycosis, we compared the activity of combination therapy (isavuconazole + micafungin) with pla ... | 2017 | 27798213 |
| expression and characterization of a novel 1,3-regioselective cold-adapted lipase from rhizomucor endophyticus suitable for biodiesel synthesis. | the biodiesel production can be carried out by transesterification using either chemical or enzymatic process. the enzymatic transesterification is more promising as it offers an environmental friendly option compared to the chemical process, where the lipases with high catalytic efficiency and good stability play a key role. hence, it is of great value to identify novel lipases which are suitable for biodiesel production. | 2016 | 27081399 |
| species boundaries and nomenclature of rhizopus arrhizus (syn. r. oryzae). | rhizopus arrhizus (mucorales, mucoromycotina) is the prevalent opportunist worldwide among the mucoralean species causing human infections. on the other hand the species has been used since ancient times to ferment african and asian traditional foods and condiments based on ground soybeans. as producer of organic acids and hydrolytic enzymes it is widely applied in food industry and biotechnology. using a set of 82 strains we studied phylogenetic and biological species boundaries within rhizopus ... | 2014 | 25266947 |
| efficient transformation of rhizopus delemar by electroporation of germinated spores. | high efficient transformation of mycelial fungi is essential to both metabolic engineering and physiological analysis of these industrially important microorganisms. however, transformation efficiencies for mycelial fungi are highly restricted by difficulties in colony formation and competent cell preparation. in this work, an innovative transformation procedure that could significantly improve the efficiency of colony formation and transformation process has been established for a typical mycel ... | 2014 | 24886837 |
| molecular characterization of β-fructofuranosidases from rhizopus delemar and amylomyces rouxii. | of the 19 strains of rhizopus delemar deposited as rhizopus oryzae, seven of them, nbrc 4726, nbrc 4734, nbrc 4746, nbrc 4754, nbrc 4773, nbrc 4775, and nbrc 4801, completely hydrolyzed exogenous sucrose and fructooligosaccharides. the sucrose-hydrolyzing enzyme was purified from the culture filtrate of r. delemar nbrc 4754 and classified to β-fructofuranosidase, similar to that of amylomyces rouxii cbs 438.76. fragments including β-fructofuranosidase genes (suca) of seven strains of r. delemar ... | 2013 | 23180124 |
| the rhizoferrin biosynthetic gene in the fungal pathogen rhizopus delemar is a novel member of the nis gene family. | iron is essential for growth and in low iron environments such as serum many bacteria and fungi secrete ferric iron-chelating molecules called siderophores. all fungi produce hydroxamate siderophores with the exception of mucorales fungi, which secrete rhizoferrin, a polycarboxylate siderophore. here we investigated the biosynthesis of rhizoferrin by the opportunistic human pathogen, rhizopus delemar. we searched the genome of r. delemar 99-880 for a homologue of the bacterial nrps-independent s ... | 2017 | 28610916 |
| the role of aquaporins in ph-dependent germination of rhizopus delemar spores. | rhizopus delemar and associated species attack a wide range of fruit and vegetables after harvest. host nutrients and acidic ph are required for optimal germination of r. delemar, and we studied how this process is triggered. glucose induced spore swelling in an acidic environment, expressed by an up to 3-fold increase in spore diameter, whereas spore diameter was smaller in a neutral environment. when suspended in an acidic environment, the spores started to float, indicating a change in their ... | 0 | 26959825 |
| production of cellulosic organic acids via synthetic fungal consortia. | consolidated bioprocessing (cbp) is a potential breakthrough technology for reducing costs of biochemical production from lignocellulosic biomass. production of cellulase enzymes, saccharification of lignocellulose, and conversion of the resulting sugars into a chemical of interest occur simultaneously within a single bioreactor. in this study, synthetic fungal consortia composed of the cellulolytic fungus trichoderma reesei and the production specialist rhizopus delemar demonstrated conversion ... | 2017 | 29205274 |
| sustainable carbon sources for microbial organic acid production with filamentous fungi. | the organic acid producer aspergillus oryzae and rhizopus delemar are able to convert several alternative carbon sources to malic and fumaric acid. thus, carbohydrate hydrolysates from lignocellulose separation are likely suitable as substrate for organic acid production with these fungi. | 2017 | 29075326 |
| comparative proteomics of rhizopus delemar atcc 20344 unravels the role of amino acid catabolism in fumarate accumulation. | the filamentous fungus rhizopus delemar naturally accumulates relatively high amounts of fumarate. although the culture conditions that increase fumarate yields are well established, the network underlying the accumulation of fumarate is not yet fully understood. we set out to increase the knowledge about fumarate accumulation in r. delemar. to this end, we combined a transcriptomics and proteomics approach to identify key metabolic pathways involved in fumarate production in r. delemar, and pro ... | 2017 | 28382234 |
| prophylaxis with isavuconazole or posaconazole protects immunosuppressed mice from pulmonary mucormycosis. | we assessed prophylactic or continuous therapy of isavuconazole, posaconazole, or voriconazole in treating pulmonary murine mucormycosis. in the prophylaxis studies, only isavuconazole treatment resulted in significantly improved survival and lowered tissue fungal burden of immunosuppressed mice infected with rhizopus delemar. in the continuous treatment studies, isavuconazole and posaconazole, but not voriconazole, equally prolonged survival time and lowered tissue fungal burden compared to pla ... | 2017 | 28264840 |
| mucormycosis outbreak associated with hospital linens. | mucormycosis is an invasive fungal infection with a high fatality rate. we investigated an outbreak of mucormycosis in a pediatric hospital to determine routes of pathogen transmission from the environment and prevent additional infections. | 2014 | 24667485 |
| isavuconazole therapy protects immunosuppressed mice from mucormycosis. | we studied the in vitro and in vivo efficacies of the investigational drug isavuconazole against mucormycosis due to rhizopus delemar. isavuconazole was effective, with mic and minimal fungicidal concentration (mfc) values ranging between 0.125 and 1.00 μg/ml. a high dose of isavuconazole prolonged the survival time and lowered the tissue fungal burden of cyclophosphamide/cortisone acetate-treated mice infected with r. delemar and was as effective as a high-dose liposomal amphotericin b treatmen ... | 2014 | 24492363 |