Publications

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
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
[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
[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
[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
[effect of fungi on the strength of asphalt road surface].		1979	113651
[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
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
microbial synthesis of sugar derivatives of d-pantothenic acid.		1979	108510
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
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
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
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
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
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
respiratory hazards from proteolytic enzymes.		1978	76211
[the role of polyprenols in sugar moiety transfer (author's transl)].		1977	67595
the synthesis of pectinases by mutant of aspergillus niger 36 in beet pulp medium.		1976	65114
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
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
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
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
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
citrate regulation of nadp+-specific isocitrate dehydrogenase of aspergillus niger [proceedings].		1978	33856
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
[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
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
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
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
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
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
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
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
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
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
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
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
studies on xylan degrading enzymes. i. purification and characterization of endo-1,4-beta-xylanase from aspergillus niger str. 14.		1977	19078
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
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
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
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
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
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
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
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
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
purification and properties of d-amino acid oxidas of aspergillus niger.		1976	13036
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
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. 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
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
current status of treatment in storage disorders.		1976	10023
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
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
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
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
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
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
formation of optically-active metabolites of the organophosphorus pesticide phorate by nematodes and microorganisms.		1976	5242
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
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
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
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
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
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
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