| formation and cleavage of 2-keto-3-deoxygluconate by 2-keto-3-deoxygluconate aldolase of aspergillus niger. | 2-keto-3-deoxygluconate aldolase of aspergillus niger, an enzyme that has not been reported previously, was purified 468-fold. maximal activity was obtained at ph 8.0 and 50 c. the enzyme exhibited relative stereochemical specificity with respect to glyceraldehyde. the km values for 2-keto-3-deoxygluconate, glyceraldehyde, and pyruvate were 10, 13.3, and 3.0 mm, respectively. the effects of some compounds and inhibitors on enzyme activity were examined. stability of the enzyme under different co ... | 1975 | 358 |
| effect of ph on the enzymic activity of the fungi trichothecium roseum and aspergillus niger hydrolyzing nonstarch polysaccharides. | the purpose of the study was to determine optimal ph values for the enzymic activity of the fungi trichothecium roseum and aspergillus niger hydrolyzing nonstarch polysaccharides of barley and disrupting cell walls (cytolysis) of grain, the so called cytolytic enzymes. the effect of the acidity of the medium on the stability of these enzymes was also investigated. in this connection total cytolytic activity (i. e. total activity of the enzymes hydrolyzing nonstarch polysaccharides of cell walls ... | 1975 | 1722 |
| effect of the composition of the nutrient medium on the synthesis of acid-fast alpha-amylase by different strains of aspergillus. | the capacity of 86 strains of the aspergillus fungus to synthesize acid stable alpha-amylase was examined. the strains of asp. niger showing a high capacity of synthesizing the enzyme were isolated. repeated cultivation of the selected cultures on the minoda agar medium led to a 200% increase in the enzyme activity in the submerged culture. addition of sodium nitrate to the minoda medium during submerged cultivation allowed a 3-fold increase of the synthesis of acid stable alpha-amylase. | 1975 | 1736 |
| conditions for splitting protodioscine--the main glycoside from tribulus terrestris l. by the enzymatic preparation from aspergillus niger bkmt-33. | the conditions for splitting protodioscine--the main steroid saponine isolated from tribulus terrestris l. by the enzymic preparation of aspergillus niger str. bkmt-33 were investigated. the optimal conditions were found to be as follows: ph 4-5, temperature 30-37 degrees (the substrate concentration--5 mg%, concentration of the enzymic preparation--1%). under these conditions the enzymolysis continued 24 hours. mg+2 and k+ ions accelerated the reaction twice. as a result of the enzymic hydrolys ... | 1975 | 1743 |
| purification and characterization of an extracellular exo-d-galacturonanase of aspergillus niger. | a d-galacturonanase (ec 3.2.1.67) catalyzing the degradation of d-galacturonans by terminal action pattern was purified from a culture filtrate of aspergillus niger by a procedure including the salting-out with ammonium sulfate, precipitation by ethanol, chromatography on deae-cellulose, and gel chromatography on sephadex g-100. the obtained preparation was slightly contaminated by an enzymically inactive protein fraction. maximum activity and stability of the enzyme was observed at ph 5.2. the ... | 1976 | 2310 |
| enzyme-catalyzed redox reactions with the flavin analogues 5-deazariboflavin, 5-deazariboflavin 5'-phosphte, and 5-deazariboflavin 5'-diphosphate, 5' leads to 5'-adenosine ester. | the ability of 5-deazaisoalloxazines to substitute for the isoalloxazine (flavin) coenzyme has been examined with several flavoenzymes. without exception, the deazaflavin is recognized at the active site and undergoes a redox change in the presence of the specific enzyme substrate. thus, deazariboflavin is reduced catalytically by nadh in the presence of the beneckea harveyi nad(p)h:(flavin) oxidoreductase, the reaction proceeding to an equilibrium with an equilibrium constant near unity. this i ... | 1976 | 3207 |
| formation and some factors influencing the activity of progesterone hydroxylases by aspergillus niger. | the formation of progesterone hydroxylases by aspergillus niger 173 was investigated. the constitution of the fermentation medium influenced both the yield and the type of enzymes catalyzing the transformation of progesterone. the enzyme yield also varied with the ph value at which induction was performed as well as with the buffer used. the transformation activity of progesterone was more pronounced with mycelia induced in citrate-phosphate than in phosphate buffer. the results demonstrated tha ... | 1975 | 3926 |
| formation of optically-active metabolites of the organophosphorus pesticide phorate by nematodes and microorganisms. | | 1976 | 5242 |
| kinetic studies on citric acid production by aspergillus niger. ii. the two-stage process. | a two-stage process of submerged citric acid fermentation with replacement of growth medium by fermentation medium has been worked out. the optimum composition of mineral nutrients and ph of the fermentation medium of the second stage of the process were determined. an addition of 0.5 g/l of nh4no3 as nitrogen source and 0.1 g/l of mgso4-7h2o as magnesium source ensured effective conversion of sucrose to citric acid. an addition to kh2po4, on the other hand, was definitely unfavourable as it con ... | 1975 | 5858 |
| adsorption, desorption, and activity of glucose oxidase on selected clay species. | the adsorption of the enzyme glucose oxidase (ec 1.1.3.4) to clays followed the pattern described for other proteins as being ph dependent. maximum adsorption occurred at or below the isoelectric point of the enzyme. the amount of enzyme adsorbed to clay was influenced by the type of clay used, and also the saturating cations. initially adsorbed enzyme showed low specific activities, and as amounts of enzyme adsorbed approached maximum stauration of clay, specific activities increased approachin ... | 1976 | 6139 |
| effect of sugars, hydrogen ion concentration and ammonium nitrate on the formation of citric acid by aspergillus niger. | aspergillus niger mulder strain when grown on a synthetic medium containing urea as the sole source of nitrogen at ph 5.2, formed a mixture of citric and gluconic acids. on growing the organism at ph 2.0 the gluconic acid content was reduced but citric acid yield remained low. addition of nh4no3 to the medium lowered the gluconic acid yields to undetectable levels with a simultaneous increase in the citric acid content. of the sugars used for the production of citric acid, sucrose in an unautocl ... | 1976 | 7101 |
| a new method using p-benzoquinone for coupling antigens and antibodies to marker substances. | a method using p-benzoquinone for coupling antigens and antibodies to enzymes and erythrocytes is described. the method involves the treatment of proteins (or polysaccharides) at ph 6 or 7 with an excess of p-benzoquinone. after removal of the unreacted reagent by gel filtration, the "activated" proteins were coupled at ph 8-9 with enzymes or erythrocytes. biological activities of the proteins were not substantially modified by this treatment since 80-100% of the antigen binding capacity was fou ... | 1976 | 7179 |
| antifungal properties of alpha,omega-alkanedicarboxylic acids and their dimethyl esters. | thirteen alpha, omega-alkanedicarboxylic acids (c2-c12, c14, and c16) and their dimethyl esters were tested against aspergillus niger, trichoderma viride, and myrothecium verrucaria in sabourauc dextrose agar at ph 4.0 and 5.6. toxicity to canadida albicans, trichophyton mentagrophytes, and mucor mucedo was determined in the same medium at ph 5.6 and 7.0 in the absence and presence of 10% beef serum. the dicarboxylic acids possessed very poor to no antifungal activity against all six fungi. the ... | 1976 | 9194 |
| tryptophanyl and carboxylic acid residues in the active centre of glucoamylase i from aspergillus niger. | the ph-dependence of the photo-oxidation of l-tryptophan, in the presence of rose bengal and methylene blue, has been investigated. true, initial rate constants were determined in order to circumvent errors due to secondary processes. photo-oxidation of glycoamylase i from a. niger in the presence of methylene blue or rose bengal resulted in a ph-dependent loss of enzymic activity, which was analogous to the destruction of free l-tryptophan during photo-oxidation. the loss of enzymic activity wa ... | 1976 | 9197 |
| current status of treatment in storage disorders. | | 1976 | 10023 |
| metabolism of dl-(+/-)-phenylalanine by aspergillus niger. | a fungus capable of degrading dl-phenylalanine was isolated from the soil and identified as aspergillus niger. it was found to metabolize dl-phenylalanine by a new pathway involving 4-hydroxymandelic acid. d-amino acid oxidase and l-phenylalanine: 2-oxoglutaric acid aminotransferase initiated the degradation of d- and l-phenylalanine, respectively. both phenylpyruvate oxidase and phenylpyruvate decarboxylase activities could be demonstrated in the cell-free system. phenylacetate hydroxylase, whi ... | 1976 | 10273 |
| the structure and function of acid proteases. v. comparative studies on the specific inhibition of acid proteases by diazoacetyl-dl-norleucine methyl ester, 1,2-epoxy-3-(p-nitrophenoxy) propane and pepstatin. | comparative studies have been made on the effects of diazoacetyl-dl-norleucine methyl ester (dan), 1,2-epoxy-3-(p-nitrophenoxy)propane (epnp) and pepstatin on acid proteases, including those from acrocylindrium sp., aspergillus niger, aspergillus saitoi, mucor pusillus, paecilomyces varioti, rhizopus chinensis, and trametes sanguinea, and also porcine pepsin ec 3.4.23.1 and calf rennin ec 3.4.23.4 for comparative purposes. these enzymes were rapidly inactivated at similar rates and in 1:1 stioch ... | 1976 | 10290 |
| cleavage of alpha-l-arabinofuranoside, beta-d-glucopyranoside and beta-cellobioside of 4-nitrophenol by enzymes of various fungi - a contribution to increase the selectivity of tumor therapy. | to carry out long-term experiments as part of a therapy concept of malignant tumours using inactive transport forms of cancerostatic substances and their specific cleavage in the acidic ph region of the tumours by application of extraneous enzymes, we require enzymes with similar catalytic and pharmacokinetic properties which differ from each other in immunological respect. in the search for such enzymes, the alpha-l-arabinofuranosidases from 12 different fungi, among them 9 basidiomycetes, were ... | 1976 | 10689 |
| the structure and function of acid proteases. vi. effects of acid protease-specific inhibitors on the acid proteases from aspergillus niger var. macrosporus. | 1. the type b acid protease from aspergillus niger var. macrosporus was inactivated by reaction with diazoacetyl-dl-norleucine methyl ester (dan), dl-1-diazo-3-tosylamido-2-heptanone (dth), and l-1-diazo-3-tosylamido-4-phenyl-2-butanone (dtpb) in the presence of cupric ions. the reaction with dan took place with 1:1 stoichiometry. the enzyme was also inactivated by reaction with 1, 2-epoxy-3-(p-nitrophenoxy)-propane (epnp) with concomitant incorporation of approximately two epnp molecules per mo ... | 1976 | 12156 |
| purification and properties of d-amino acid oxidas of aspergillus niger. | | 1976 | 13036 |
| lytic enzymes in the autolysis of filamentous fungi. | the degrees of autolysis attained by five different genera of filamentous fungi during an incubation period of 60 days, under the same culture conditions were: 87.3% for penicillium oxalicum; 65.9% for neurospora crassa; 62.7% for polystictus versicolor; 51.7% for aspergillus niger and 23.5% for nectria galligena. n. crassa, a. niger and p. versicolor reached the end of the autolysis during this incubation period (60 days), whereas p. oxalicum and n. galligena did not. the excretion of the lytic ... | 1976 | 13304 |
| sustrate-specificity of glucomylase (e.c. 3.2.1.3) exemplified by p-nitroaniline n-glucosides. | the present paper supplements the previous investigations on the mechanism of reactions catalyzed by amylolytic enzymes. the performed experiments corroborated the data on transglucosylative properties of animal glucoamylases which were found to depend on the structure and concentration of substrate. the p-nitroanilines were first introduced in this type of research enabling to find the differences of activity mechanism of animal glucoamylases and aspergillus niger glucoamylase. in complement to ... | 1976 | 13765 |
| purification and properties of one component of acid phosphatase produced by aspergillus niger. | one component, the i form, of acid phosphatase (orthophosphoric-monoester phosphohydrolase (acid optimum), ec 3.1.3.2) produced by aspergillus niger was purified from the mycelial extract. the purified enzyme was homogenous on sephadex g-200 gel filtration, disc electrophoresis and heat inactivation. the purified enzyme was studied and the following results were obtained: 1. the enzyme catalyzed the hydrolysis of a wide variety of phosphomonoesters, but not that of bis(p-nitrophenyl)phosphate, a ... | 1977 | 13843 |
| glycoprotein enzymes secreted by aspergillus niger: purification and properties of alpha-glaactosidase. | an alpha-galactosidase (alpha-d-galactoside galactohydrolase ec 3.2.1.22) was purified to homogeneity from the culture filtrate of aspergillus niger. the enzyme had an apparent molecular weight of 45,000 and was a glycoprotein. radioactive enzyme was prepared by growing cells in 14cfructose and this enzyme was used to prepare 14c-labeled glycopeptides. the glycopeptides emerged from sephadex g-50 between stachyose and the glycopeptide from ovalbumin. based on calibration of the column with vario ... | 1977 | 14112 |
| use of amylum derivatives for isolation of amylolytic enzymes. | in a leading article literature is reviewed concerning isolation of amylolytic enzymes by adsorption on differently modified starches, resp. on other adsorbents. deae amylum, deahp amylum and deae-sephadex a 25 were found to be most suitable adsorbents. the other adsorbents examined did not reach claimed parameters. | 1977 | 15219 |
| fractionation and purification of endo-1,4-beta-xylanases and exo-1,4-beta-xylosidases of aspergillus niger. | two endo-1,4-beta-zylanases (m. w. 24,000 and 41,000) and six exo-1,4-beta-xylosidases, differing in their molecular weights and isoelectric points, were found in a xylanase preparation from aspergillus niger, using different methods of fractionation. an electrophoretically homogeneous exo-1,4-beta-xylosidase (m. w. 30,000) purified 120-fold, with pi 4.6, having optimal effect on methyl-beta-d-xyloside at ph 3.0 was obtained. exo-1,4-beta-xylosidase splits off xylose from the ends of the xylan c ... | 1977 | 15659 |
| gluconic acid forming enzymes in aspergillus niger (author's transl). | at least three gluconic acid forming enzymes were identified in cell-free extracts of aspergillus niger: glucose oxidase (ec 1.1.3.4), a glucose dehydrogenase (ec 1.1.99.10), and an enzyme or a mixture of enzymes catalyzing the cleavage of 6-phosphogluconate into gluconate and inorganic phosphate. 2,6-dichlorphenolindophenol was one of the hydrogen acceptors in vitro of the glucose dehydrogenase. some properties of this enzyme (km values, ph-dependence, substrate and hydrogen acceptor specificit ... | 1977 | 16416 |
| effect of cadmium on fungi and on interactions between fungi and bacteria in soil: influence of clay minerals and ph. | fungi (rhizopus stolonifer, trichoderma viride, fusarium oxysporum f. sp. conglutinans, cunninghamella echinulata, and several species of aspergillus and penicillium) tolerated higher concentrations of cadmium (cd) when grown in soil than when grown on laboratory media, indicating that soil mitigated the toxic effects of cd. in soil amended with clay minerals, montmorillonite provided partial or total protection against fungistatic effects of cd, whereas additions of kaolinite provided little or ... | 1977 | 18085 |
| purification and properties of a cellulase from aspergillus niger. | a cellulolytic enzyme was isolated from a commercial cellulase preparation form aspergillus niger. a yield of about 50mg of enzyme was obtained per 100g of commerial cellulase. the isolated enzyme was homogeneous in the ultracentrifuge at ph 4.0 and 8.0, and in sodium dodecyl sulphate/polyacrylamide-gel electrophoresis but showed one major and two minor bands in disc gel electrophoresis. no carbohydrate was associated with the protein. amino acid analysis revealed that the enzyme was rich in aci ... | 1977 | 19015 |
| studies on xylan degrading enzymes. i. purification and characterization of endo-1,4-beta-xylanase from aspergillus niger str. 14. | | 1977 | 19078 |
| metabolism of mandelic acid by neurospora crassa. | preliminary studies on the metabolism of manelic acid by neurospora crassa reveal the operation of a pathway for its degradation which involves benzoyl formic acid, benzaldehyde, benzoic acid, 4-hydroxybenzoic acid, and protocatechuic acid as the intermediates. this pathway is different from the followed by bacterial systems and is the same as that observed in aspergillus niger. | 1977 | 21739 |
| selective tumor dna synthesis inhibition: in vivo prodrug activation by an exogenous enzyme. | using the combination of alpha-l-arabinofuranosidase from aspergillus niger with beta-peltatin a-alpha-l-arabinofuranoside, the selective effect of a new cancer of chemotherapy method based on a ph-dependent activation of cancerostatic prodrugs by exogenous enzymes was studied. in comparative experiments the selectivity of prodrug activation was measured by 3h-thymidine incorporation in tumor and normal tissues of cba mice inoculated im with the transplantable mammary carcinoma, ma-21224. the re ... | 1977 | 21745 |
| chemical modification of cellulase from aspergillus niger. | n-bromosuccinimide completely inactivated the cellulase, and titration experiments showed that oxidation of one tryptophan residue per cellulase molecule coincided with 100% inactivation. cm-cellulose protected the enzyme from inactivation by n-bromosuccinimide. the cellulase was inhibited by active benzyl halides, and reaction with 2-hydroxy-5-nitrobenzyl bromide resulted in the incorporation of 2.3 hydroxy-5-nitrobenzyl groups per enzyme molecule; one tryptophan residue was shown to be essenti ... | 1977 | 23759 |
| active groups of extracellular endo-d-galacturonanase of aspergillus niger derived from ph effect on kinetic data. | in an attempt to characterize the groups essential for the catalytic action extracellular endo-d-galacturonanase of aspergillus niger (poly (1,4-alpha-d-galacturonide) glycanohydrolase, ec 3.2.1.15) the behaviour of the kinetic parameters as a function of ph was examined. the dependence of kcat and kcat/km on ph suggests that two dissociable groups are involved, for which the pk values of about 3.0 and 5.0 in the free enzyme and 3.06 and 5.72 in the catalytic complex were found at 30 degrees c. ... | 1978 | 24473 |
| energy-driven uptake of humic acids by aspergillus niger. | the uptake of humic acids by mycelia of aspergillus niger was demonstrated to be energy-dependent with a sensitivity to sodium azide and to 2,4-dinitrophenol. greater uptake of humic acids by submerged mycelium occurred at ph 3.0 and at 32 degrees c. the rate of uptake was influenced by the concentration of humic acids with an apparent km of 0.2 grams/ml and with a vmax of 0.13 mg humic acids per gram mycelial dry weight.10 min-1. in the absence of added energy source, vmax of 0.05 mg humic acid ... | 1978 | 26456 |
| antifungal properties of 2-alkynoic acids and their methyl esters. | thirteen 2-alkynoic acids and their methyl esters (c3--c12, c14, c16, and c18) were tested against aspergillus niger, trichoderma viride, and myrothecium verrucaria in sabouraud dextrose agar at ph 4.0 and 5.6. toxicity to candida albicans, trichophyton mentagrophytes, and mucro mucedo was determined in the same medium at ph 5.6 and 7.0 in the absence and presence of 10% beef serum. the fungitoxicity of the acids was influenced by chain length, ph of the medium, and absence or presence of adsorb ... | 1978 | 26458 |
| effect of the composition of the medium and the conditions of aspergillus foetidus cultivation on the biosynthesis of glucoamylase. | the optimal conditions for biosynthesis of exocellular glucoamylase were found in the course of submerged cultivation of aspergillus foetidus atcc 14916: ph 4.5 at the beginning of cultivation, cultivation for four days, a temperature of 30 degrees c, and an aeration in the fermenter of 1.5 volumes of the air per 1 volume of the medium with a stirring of 280 rpm. the material can be inoculated either as spores (1 x 10(7) spores per 100 ml of the medium) or a material germinated from spores (5% b ... | 1978 | 26852 |
| determination of glucose oxidase oxidation-reduction potentials and the oxygen reactivity of fully reduced and semiquinoid forms. | the oxidation-reduction potential values for the two electron transfers to glucose oxidase were obtained at ph 5.3, where the neutral radical is the stable form, and at ph 9.3, where the anion radical is the stable form. the midpoint potentials at 25 degrees were: ph 5.3 efl1ox + e- h+ equilibrium eflh. em1 = -0.063 +/- 0.011 v eflh. + e- + h+ equilibrium eflredh2 em2 = -0.065 +/- 0.007 v ph 9.3 eflox + e- efi- em1 = -0.200 +/- 0.010 v efi- + e- + h+ equilibrium eflredh- em2 = -0.240 +/- 0.005 v ... | 1978 | 27511 |
| kinetics and stability of glucooxidase from penicillium vitale. | the kinetics, thermal stability and ultrasonic resistance of glucosoxidase from penicillium vitale have been investigated. its oxidative constant is close to, catalytic constant is 1.7 times less and the reductive constant is 5.4 times more than the respective constants of the enzyme from aspergillus niger. the relationship between the thermal inactivation constant (k(i)=2.1 pt 15.3. the same relationship is true of the ultrasonic inactivation constant and ph in the ph range of 6.5-8.0. in a mor ... | 1978 | 27781 |
| utilization of industrial and agricultural by-products for fungal amylase production. | attempts were made for using industrial and agricultural by-products and wastes as carbon and nitrogen sources in fermentation medium for alpha-amylase production by aspergillus niger nrrl-337. the original carbon source of the basal medium was replaced by one of the following materials: rice bran, wheat bran, corn bran, corn starch, cane molasses, and glucose syrup. rice bran proved to be the best carbon source that secured the highest amylase activity. the nitrogen source of the basal medium w ... | 1978 | 28620 |
| experiments to increase the selectivity of tumor chemotherapy by means of in vivo activation of transport forms of cancerostatics by exogenous enzymes. | a significant tumor damaging effect (growth inhibition) on transplanted syngeneic sarcoma in mouse was obtained by means of ph-dependent activation of a transport form of a cancerostatic drug by an enzyme foreign to the organism. this effect was achieved by combined administration of 8-0-(alpha-l-arabinofuranosyl)beta-peltatin-a as a transport form of beta-peltatin-a and the exogenous enzyme alpha-l-arabinofuranosidase from aspergillus niger and additional increase of the acidity of the tumor by ... | 1978 | 29245 |
| [acid-stable and acid-unstable alpha-amylases of the mold fungi aspergillus]. | acid-sable alpha-amylase of asp. niger and acid-unstable, alpha-amylase of asp. oryzae were studied. it was demonstrated, that beside being a more acid-stable properties, alpha-amylase asp. niger has increased thermal stability as compared to alpha-amylase asp. oryzae. the molecular weights of acid-stable alpha-amylase and acid-unstable alpha-amylase are 58 000 and 51 000, respectively. the amino acid composition, and the c- and n-terminal amino acids of both forms of alpha-amylases were determi ... | 1978 | 31203 |
| mannosyl transfer by membranes of aspergillus niger: mannosylation of endogenous acceptors and partial analysis of the products. | a smooth membrane fraction of aspergillus niger catalyzed the transfer of mannose from gdp-mannose to endogenous lipid and protein acceptors. the mannolipid was acidic, as judged by diethylaminoethyl-cellulose chromatography, and had a mobility similar to ficaprenyl phosphate on thin-layer chromatograms. mannose transfer occurred optimally at ph 6.5 to 7.5 and required mn(2+) for use of the protein as acceptor, but either mn(2+) or mg(2+) with the lipid as acceptor. glycopeptides of the mannosyl ... | 1979 | 33149 |
| citrate regulation of nadp+-specific isocitrate dehydrogenase of aspergillus niger [proceedings]. | | 1978 | 33856 |
| pepstatin-insenstive acid proteases from scytalidium lignicolum. kinetic study with synthetic peptides. | a kinetic study was conducted on the acid proteases a-1 and a-2 from scytalidium lignicolum using synthetic peptides as substrates. almost maximum activity was attained with n-acylated tetrapeptides as the molecular size of substrates was increased. suitable amino acid residues were required at the p1-p2 and p1'-p2' positions [notation of schechter and berger (14)]. hydrophobic or bulky residues such as leucine were specifically required at the p1 and p1' positions, with the specificity at the l ... | 1979 | 34596 |
| interaction of radical anion probes with glucoamylase i from aspergillus niger. | the radical anions (scn)2.- and br2.- produced during a pulse radiolysis of the respective potassium salts have been used to study the tryptophan residues of the glucoenzyme, glucoamylase i (ec 3.2.1.3.). at neutral ph, br2.- reacted with the tryptophan residues of glucoamylase i as expected from previous studies of proteins and free amino acids. however, (scn)2.- at neutral and high ph was surprisingly unreactive towards the native enzyme. reaction did occur, however, between (scn)2.- and gluco ... | 1978 | 38219 |
| bioconversion of wheat straw and wheat straw components into single-cell protein. | several fungi (aspergillus niger, a. terreus, cochliobolus specifer, myrothecium verrucaria, rhizoctonia solani, spicaria fusispora, penicillium sp., and gliocladium sp.) were isolated from decomposing wheat straw and tested for their ability to utilize whole straw and its components, holocellulose (hemicellulose and cellulose) and cellulose, for the production of single-cell protein (scp). it was found that c. specifer was the most efficient fungus for protein synthesis with the three substrate ... | 1979 | 38899 |
| comparison of fungal glucose oxidases. chemical, physicochemical and immunological studies. | glucose oxidases (beta-d-glucose:oxygen 1-oxidoreductase, ec 1.1.3.4) from two fungal genera (aspergillus and penicillium) were studied chemically, physicochemically and immunologically to elucidate the similarities and dissimilarities between these enzymes. investigation of circular dichroism spectra revealed that these enzymes proteins possess essentially identical conformations. however, differences found in thermal inactivation parameters, catalytic parameters and quantitative immunological ... | 1976 | 59610 |
| effect of acetic and trans-aconitic acids on citric acid production by aspergillus niger. | the effect of acetic and trans-aconitic acids on citric acid production by a. niger at different ph values was studied. the presence of acetic acid at ph 2 prevented spore germination, while it decreased the fungal growth and citric acid production at other ph values. in the presence of trans-aconitic acid the inhibition was less marked at lower than at higher ph values. | 1976 | 62499 |
| the synthesis of pectinases by mutant of aspergillus niger 36 in beet pulp medium. | | 1976 | 65114 |
| [the role of polyprenols in sugar moiety transfer (author's transl)]. | | 1977 | 67595 |
| respiratory hazards from proteolytic enzymes. | | 1978 | 76211 |
| some properties of partially purified phytase from aspergillus niger. | phytase was purified from aspergillus niger culture fluid by molecular sieve filtration on sephadex g-200, followed by thermal inactivation of acid phosphatase and cm-cellulose chromatography. the 12-fold purified enzyme had two ph optima at 2.7 and 5.5 and was characterized by high thermal stability in alkaline environment and broad substrate specificity. the michaelis constant of phytase relative to myo-inositol hexaphosphate sodium salt is 4.8 x 10(-4) m and activation energy 9,217 cal/mole. ... | 1978 | 76423 |
| characterization of antigens from aspergillus fumigatus. iii. comparison of antigenic relationships of clinically important aspergilli. | antigenic relationships between strains of aspergillus fumigatus, aspergillus fumigatus var. elipticus, aspergillus phialiseptus, aspergillus flavus, and aspergillus niger were analyzed by fused rocket immunoelectrophoresis and by skin tests. seventy-three to 89 % of the numbers of antigens detected between strains and species of the a. fumigatus series were shared. the degree of sharing between antigens of a. flavus, a. fumigatus series, and a. niger was much lower and ranged from 19 to 35 %. i ... | 1979 | 92906 |
| fungal nucleic acids as interferon inducers. | nucleic acids isolated from the fungi aspergillus niger x11, piptoporus betulinus and ganoderma applanatum reduced the number of vaccinia virus plaques in chick embryo fibroblast (cef) tissue culture and when administered intravenously to white mice protected them against lethal infection with tick borne encephalitis virus strain k5 (tbe). in cef tissue culture the nucleic acids of the studied fungi were found to induce small but detectable amounts of a substance with the character of interferon ... | 1979 | 94746 |
| late onset asthma due to inhalation of aspergillus niger. | clinical observations and immunological evidence are presented to support a diagnosis of late onset asthma due to exposure to aspergillus niger in a 70-year-old man. asthma occurred on only three occasions, each time approximately 6 hr after exposure to an area containing aspergillus niger. his sputum culture contained the same organism. immunological correlates using the aspergillus niger extract included positive immediate and late skin tests, histamine release from leukocytes, and serum preci ... | 1975 | 95654 |
| determination of the minimal inhibitory concentration of amphotericin b and miconazole for 21 strains of aspergillus. | the susceptibility of 21 strains of aspergillus (11 of a. fumigatus, 8 of a, niger, and 2 of a. flavus) isolated from human pathologic specimens to amphotericin b and miconazole has been comparatively studied. determination of the minimal inhibitory concentration of both drugs in a liquid medium showed a noticeably variability for the different strains. the values obtained for amphotericin b varied between 0.25 microgram/ml (2 strains) and 1.25 microgram/ml (5 strains) after 48 hours, and betwee ... | 1978 | 104180 |
| effect of some agents on the activity of cell-free progesterone 11 alpha-hydroxylase and 11 beta-hydroxylase from aspergillus niger 12y. | the effect of some agents on the activity of cell-free progesterone 11 alpha-hydroxylase and 11 beta-hydroxylase from aspergillus niger 12y was studied. calcium chloride, sodium chloride, magnesium sulphate, copper sulphate, and edta inhibited 11 alpha-hydroxylase and 11 beta-hydroxylase, while mercuric chloride inhibited only 11 alpha-hydroxylase. inhibition of both the enzymes was also brought about by iodine, p-chloromercuribenzoate, iodoacetic acid, maleic acid, and cystine as well as potass ... | 1978 | 107681 |
| microbial synthesis of sugar derivatives of d-pantothenic acid. | | 1979 | 108510 |
| 2-deoxy-d-lyxo-hexonic acid from 2-deoxy-d-lyxo-hexose by pseudomonas aeruginosa fermentation. | aerobic fermentation of media or solutions containing 2-deoxy-d-lyxo-hexose and calcium carbonate by bacterial cells capable of oxidizing aldoses to aldonic acids was used to prepare 2-deoxy-d-lyxo-hexonic acid; the acid was isolated in a 62% yield in the form of its 1,4-lactone. | 1979 | 110658 |
| [effect of the fungal metabolites of aspergillus flavus and a. niger on the tissue sorptive capacity of the large intestine]. | effects of metabolites of the tiny fungi of aspergillus flavus and a. niger on the ability of mucuos membrane cells of the large intestine to absorb and exterminate certain dyes has been studied experimentally on guinea-pigs. it has been shown that under these influences, a violation of the cell and tissue metabolism in the large intestine occurs, namely, the absorbtion of the neutral red increased by 1.7 and 1.4 times, respectively, and the processes of extermination of the cells were inhibited ... | 1979 | 111381 |
| [effect of fungi on the strength of asphalt road surface]. | | 1979 | 113651 |
| [type of interactions between agarose and aspergillus niger endopolygalacturonases]. | endopolygalacturonase has been purified by binding on sepharose 6 b gel; studies on interactions between agarose and the enzymes have shown that endopolygalacturonase chromatography on sepharose 6 b was on ion-exchange chromatography and did not involve biospecific interactions. | 1978 | 114317 |
| [electron microscopic aspects of opportunistic fungi after pretreatment]. | the ultrastructive of aspergillus fumigatus, aspergillus flavus and aspergillus niger was studied when treated in vitro with 0.001, 0.01 and 0.1% econazole nitrate and econazole base. the very first morphological alterations appear faster than in normal-growing fungus and consist in a convoluted cytoplasmic membrane, large mesosomes and lomasomes and an extensive vacuolization. acid phosphatase is found in the mesosomes and lomasomes and also in the center of the vacuoles. this is an early sign ... | 1979 | 114432 |
| [fungi in pulmonary pathology]. | the author presents the most frequently observed pulmonary infections due to some opportunistic fungi (yeast, aspergillus, mucor). he describes the criterial for a correct diagnosis of pulmonary mycosis. | 1979 | 114435 |
| beta-galactosidase from aspergillus niger. separation and characterization of three multiple forms. | the enzyme beta-galactosidase (ec 3.2.1.23) from aspergillus niger was purified and resolved into three multiple forms, using molecular sieving, ion-exchange, an hydrophobic chromatography. the isolated enzyme forms accounted for 83%, 8%, and 9% of the total beta-galactosidase activity, respectively. they were glycoproteins with estimated molecular weights of 124,000, 150,000 and 173,000, isoelectric points of about 4.6, and ph optima between 2.5 and 4.0. amino acid and carbohydrate analyses sho ... | 1979 | 116848 |
| role of aspergillus and candida species in allergic bronchopulmonary mycoses. a comparative study. | allergic bronchopulmonary aspergillosis (abpa) and allergic bronchopulmonary candidiasis (abpc) has been diagnosed in 20 and 13 cases respectively with one case in common, on the basis of laboratory and clinical findings. most of the abpa cases (60%) diagnosed had an early onset of respiratory symptoms, i.e. below the age of 30 years, while most of abpc cases (69%) had a late onset of respiratory symptoms, i.e. after the age of 30 years. the precipitin bands in abpa and abpc were r-type and h-ty ... | 1979 | 118528 |
| [change in ratio between citric and oxalic acid in aspergillus niger upon exposure to mutagenic factors]. | stepwise selection of aspergillus niger producing citric acid in highly buffered molassa media was carried on in order to decrease the biosynthesis of oxalic and gluconic acids using the following mutagenic factors: diethyl sulfate, thiophosphamide, cyclophosphan, n-methyl-n'-nitro-n-nitrosoguanidine (ng), 5-fluorouracil, 1,4-bis-diazoacetylbutane, and uv. the ratio between the acids changed in mutants obtained upon the combined treatment with uv and ng. mutants producing twice as less oxalic ac ... | 1979 | 119143 |
| [on the serodiagnosis of aspergillosis: comparison of various aspergillus extracts (author's transl)]. | | 1979 | 121207 |
| [solubilization effect of phosphorus by aspergillus niger and pseudomonas fluorescens]. | | 1977 | 121319 |
| characterization of a rennin-like enzyme produced in submerged cultures of aspergillus niger. | | 1979 | 121622 |
| pyrolysis gas chromatography as an aid to the identification of penicillium species. | using pyrolysis gas chromatography it was possible to identify each of a series of eleven penicillium species and the related species aspergillus niger cmi 31821 and neurospora crassa cmi 75723, based on relative peak heights and retention times of the most reproducible peaks in each pyrogram. | 1976 | 128559 |
| [characteristics of the microflora of food products from the southwest zone of kazakhstan]. | the question as to the prevalence of toxigenic microscopic fungi in foodstuffs originating in kazakhstan is but little studied. in particular, no information on the microflora in the products coming from the south-western areas of the republic are available. the paper brings forth the results consequent upon the study of the problem in the guriev and dzhambul regions typical of this area. microflora in 317 samples of various foodstuffs (wheat grains, flour and mealy products, rice, husket millet ... | 1977 | 143127 |
| 13c nuclear magnetic resonance spectra of fungal melanins. | the 13c resonance spectra of fungal melanins from aspergillus niger, eurotium echinolatum, and stachybotrys chartarum are reported. the spectra were taken in 5% w/w solution of the substances in 0.1 n naod in d2o using the fourier-transform-technique. the spectra and possible assignments of the bands are discussed. the similarities of these spectra to those of soil humic acids are unexpectedly small. | 1978 | 149463 |
| otomycosis. | | 1978 | 153329 |
| studies on the mode of action of 5-fluorocytosine in aspergillus species. | the mode of action of 5-fluorocytosine (5-fc) was studied in three isolates of pathogenic aspergillus with varying degrees of susceptibility to the drug. distribution studies showed that susceptibility or resistance to 5-fc was not dependent on uptake of the drug. while only a small percentage of the total 5-fc taken up was found in the rna fraction of the cells, most remained in the acid-soluble intracellular pool. 5-fc, 5-fluorouracil (5-fu) and 5-fluorodeoxyuridine monophosphate (5-fd-ump) we ... | 1979 | 156110 |
| kynureninase-type enzymes of penicillum roqueforti, aspergillus niger, rhizopus stolonifer, and pseudomonas fluorescens: further evidence for distinct kynureninase and hydroxykynureninase activities. | the kynureninase-type enzymes of three fungi and one bacterium were isolated and examined kinetically for their ability to catalyze the hydrolysis of l-kynurenine and l-3-hydroxykynurenine. the phycomycete rhizopus stolonifer was found to contain a single, constitutive enzyme with km for l-3-hydroxykynurenine and l-kynurenine of 6.67 times 10-minus 6 and 2.5 times 10-minus 4 m, respectively. the ascomycetes aspergillus niger and penicillium roqueforti each contain an enzyme, induced by l-tryptop ... | 1975 | 164432 |
| carbohydrate content and regulation following injection of different glycogenolytic enzymes. | the effect of injection of glycogenolytic enzymes on tissue glycogen, blood glucose and plasma insulin was studied in mice. no effects were observed following phosphorylase, whereas the hydrolytic enzymes, alpha-amylase and acid amyloglucosidase depressed liver glycogen. in addition acid amyloglucosidase induced a decrease in blood glucose, a slight elevation of plasma insulin and a marked increase in tolbutamide-stimulated insulin release. at the doses given none of the enzymes affected muscle ... | 1975 | 165077 |
| [phylogenetic study of hepatic microsomal glucokinases]. | | 1975 | 166791 |
| galactosaminogalactan from cell walls of aspergillus niger. | a new heteropolysaccharide has been isolated by alkaline extraction of hyphal walls of aspergillus niger nrrl 326 grown in surface culture. its composition by weight, as determined by paper and gas chromatography and colorimetric analyses, is 70% galactose, 20% galactosamine, 6% glucose, and 1% acetyl. two independent experiments have been used to ascertain copolymer structure: permeation chromatography in 6 m guanidinium hydrochloride, with controlled-pore glass columns of two fractionation ran ... | 1976 | 173713 |
| partial purification and some properties of oxalacetase from aspergillus niger. | 1. oxalacetase from asperigillus niger was found to be an inducible enzyme, the induction being dependent not only on neutralisation of the acidic growth medium but also on the presence of carbonate. an explanation is proposed. 2. three methods were established for the quantitative determination of oxalacetase activity. these are based on the determination of the product acetate, on the absorbance of oxaloacetate and on coupling the hydrolysis of oxaloacetate to the oxidation of malate by nad in ... | 1976 | 179820 |
| effect of periodate oxidation on the structure and properties of glucose oxidase. | in order to elucidate the molecular structure of glucose oxidase (beta-d-glucose: oxygen 1-oxidoreductase, ec 1.1.3.4) and the roles of its carbohydrate moiety, chemical, physiochemical and immunological experiments were performed with enzyme samples before and after periodate oxidation. hydrodynamic parameters indicated that the native enzyme was a globular protein with values of 1.21 for the frictional ratio and 43 a for the stokes radius. the enzyme contained about 12% carbohydrate by weight, ... | 1976 | 182278 |
| regulation by zinc and adenosine 3',5'-cyclic monophosphate of growth and citric acid accumulation in aspergillus niger. | the citric acid fermentation by aspergillus niger is divided into two consecutive phases, growth phase when the cells proliferate but do not accumulate citrate, followed by an accumulating phase when they excrete citrate but do not proliferate. the phase alternative was controlled by the concentration of zinc: high zinc (2 mum) maintained growth phase, and a zinc 'deficiency' apparently signaled the ransition to the accumulating phase. cyclic amp affected the rates of growth and acidogenesis whe ... | 1976 | 183882 |
| [phospholipase c of fungi and staphylococci]. | the activity of phospholipase was studied in the cultural broth and cell extract of 112 strains of fungi and yeasts. the endoenzyme was detected in 19 strains of mycelial fungi, the exoenzyme was found in mucor hiemalis 50 and aspergillus niger 117. phospholipase c of m. hiemalis was purified and compared to phospholipase of staphylococci. the values of km are 8.9 and 1.07 mm, respectively, for the fungal and staphylococcal enzymes. | 1976 | 187904 |
| the molecular mechanistic and immunological properties of amine oxidases. | | 1976 | 187928 |
| [microbial resistance to formaldehyde. i. comparative quantitative studies in some selected species of vegetative bacteria, bacterial spores, fungi, bacteriophages and viruses]. | the resistence of different microorganisms to formaldehyde was determined. as test objects served gram-negative and gram-positive vegetative germs (klebsiella pneumoniae, pseudomonas aeruginosa, salmonella paratyphi-b, staphylococcus aureus, streptococcus faecalis), bacterial spores (bacillus cereus, bacillus pumilus, bacillus stearothermophilus, bacillus subtilis), fungi (aspergillus niger, candida albicans), bacteriophages (escherichia coli phages, t1, t2, t3), and viruses (adenovirus, poliomy ... | 1976 | 190825 |
| on the oligomerisation of periodate-oxidized glucose oxidase. | | 1977 | 196932 |
| [effect of low molecular weight basic proteins on mannose transport in aspergillus niger microsomes]. | basic proteins of low molecular weight activate the transfer of mannose to endogenous glycoprotein acceptors in microsomal membranes of aspergillus niger. the enhancement of mannosyltransferase activity is linked to the activation of the transport of mannose across the membrane. the role of these polycationic proteins on the membrane permeability is discussed. | 1977 | 196935 |
| purification and some properties of nad-degrading purine nucleosidase from aspergillus niger. | an enzyme which degrades nad at the adenine-ribose linkage has been purified from the mycelial extract of aspergillus niger. nadp, deamido-nad, and purine nucleosides and nucleotides were also susceptible to the hydrolytic cleavage. pyrimidine- and nicotinamide-ribose linkages were not attacked. the substrate specificity showed that the enzyme may be classified as a n-ribosyl-purine ribohydrolase (ec 3.2.2.1). the enzyme had a maximum activity in the ph range of 4.0-4.5 toward nad. the km value ... | 1978 | 208724 |
| a novel phosphodiesterase from aspergillus niger and its application to the study of membrane-derived oligosaccharides and other glycerol-containing biopolymers. | a novel phosphodiesterase has been found in commercially available extracts of aspergillus niger and has been partially purified by fractionation with acetone and chromatography on carboxymethylcellulose. the enzyme attacks glycerophosphodiester bonds with the liberation of free glycerol only. the synthetic substrate glucose 6-phospho-sn-1'(3')-glycerol is hydrolyzed with production of equivalent amounts of free glycerol and glucose 6-phosphate. similarly, the enzymic hydrolysis of sn-glycero-3- ... | 1978 | 212432 |
| [paramagnetic properties of the conidial pigments of aspergillus niger and penicillium notatum fungi isolated from the mesosphere]. | the conidia of aspergillus niger and penicillium notatum detected in the upper atmospheric layers of the earth (58--77 km) were found to contain stable paramagnetic centres (pmc) at concentrations of 0.2 x 10(18) and 1.6 x 10(18) per gram of dry biomass, respectively. aspergillin, the black pigment of asp. niger, was shown to have (0.1--0.6) x 10(18) pmc per gram of dry substance (depending on the fraction). stable paramagnetism of the conidial pigments with respect to their active protecting ac ... | 1978 | 213700 |
| mechanism of aromatic hydroxylation : the kinetic mechanism & the involvement of superoxide anions in the reaction catalyzed by m-hydroxybenzoate-4-hydroxylase from aspergillus niger (ubc-814). | | 1978 | 214394 |
| esr characterization of chitins and chitosans. | | 1979 | 226089 |
| [characterization of mitochondria of aspergillus niger from mycelium growing in surface and submerged culture conditions (author's transl)]. | this paper deals with studies on tightly coupled mitochondria present in the active citric acid producing mycelium of aspergillus niger growing in surface and submerged culture. a special homogenizer had been used for rapid extraction of mitochondria. observation in the electron microscope indicated that some of the isolated mitochondria were probably damaged during preparation. nevertheless, the crude mitochondrial fraction was capable of coupling phosphorylation to the oxidation of three diffe ... | 1979 | 232600 |
| purification, properties and induction of a specific benzoate-4-hydroxylase from aspergillus niger (ubc 814). | an inducible benzoate-4-hydroxylase has been partially purified from crude extracts of the mycelial felts of aspergillus niger. this enzyme catalyzes the transformation of benzoate to p-hydroxybenzoate with equimolar consumption of nadph and o2. it requires tetrahydropteridine as a prosthetic group. the optimum activity was found at ph 6.2 with a km value at 30 degrees c of 1.6-10-minus 4 for nadph and 1.3-10-minus 4 m for benzoate. fe-2+ (iron) is required for the enzyme activity. the enzyme is ... | 1975 | 236777 |
| patterns of action of glucoamylase isozymes from aspergillus species on glycogen. | glucoamylase isozymes from black aspergillus species have been freed of all traces of alpha-amylase by chromatography on bio-gel p-100, as evidenced by limited hydrolysis of oxidized amylose. glucoamylase i retains its ability to hydrolyze rabbit-liver glycogen rapidly. by contrast, glucoamylase ii hydrolyzes glycogen slowly, and addition of alpha-amylase to glucoamylase ii does not enhance its activity toward glycogen. these results indicate that alpha-amylase is not involved in hydrolysis of g ... | 1975 | 237628 |
| culture medium alkalinization by dermatophyes. (influence of time and temperature of incubation). | 95 dermatophyte strains (12 of trichophyton mentagrophytes, 12 of t. tonsurans, 11 of t. rubrum, 12 of t. megninii, 12 of t. violaceum, 2 of t. schoenleinii, 1 of t. soudanense, 12 of m. canis, 8 of microsporum gypseum, 1 of m. ferrugineum and 12 of epidermphoyton floccosum). 1 of aspergillus niger, 1 of a. ochraceus, 1 of paecilomyces sp., 1 of penicillium sp. and 1 of candida albicans were grown in sabouraud liquid medium for the study of ph variation over 6 weeks at room temperature and after ... | 1975 | 238130 |
| purification and characterization of aspergillus niger exo-1,4-glucosidase. | a specific exo-1,4-glucosidase (1,4-alpha-d-glucan glucohydrooase, ec 3.2.1.3) from aspergillus niger has been partially purified and subsequently characterized by biochemical, physico-chemical and optical methods. molecular sieve chromatography yields an enzyme with maximal activity at ph 4.2-4.5 close to its isoelectric point. reduction and carboxymethylation leads to complete loss of activity and o-acetylation of 3 of the 13 tyrosine residues results in loss of 20 % of the activity. sodium do ... | 1975 | 238601 |
| studies on the interaction between streptomyces pepsin inhibitor and several acid proteinases by means of a zinc(ii)-dye complex as a probe. | the zinc(ii) complex of pyridine-2-azo-p-dimethylaniline is bound to several acid proteinases, at ph 5.0, accompanied by a change is the visible absorption spectrum. streptomyces pepsin inhibitor, which was discovered by satoi and murao (satoi, s. and murao, s. (1970) agric. biol. chem. 34, 1265-1267 and satoi, s. and murao, s. (1971) agric. biol. chem. 35, 1482-1487), is also bound to acid proteinases. spectrophotometric studies with ten acid proteinases from different sources have revealed tha ... | 1975 | 238604 |
| the microbial colonization of some woods of small dimensions buried in soil. | several species of wood veneer, including some in a green undried state, were buried in various soils, and at intervals the colonists were isolated and identified. in addition, veneers were deteriorated for different periods of time, sterilized, and then reburied in the same soil. isolates were obtained before sterilization and compared with those found afterwards. in each case the colonization involved a small number of microfungi and, because similar species were repeatedly isolated, an absenc ... | 1975 | 238728 |