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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 ...197718085
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 ...1975164432
aflatoxin production by aspergillus parasiticus in a competitive environment.aspergillus parasiticus nrrl 2999 was grown in the presence of rhizopus nigricans, saccharomyces cerevisiae, acetobacter aceti, or brevibacterium linens and aflatoxin concentration was determined after 3,5,7, and 10 days of incubation at 28c. r. nigricans and s. cerevisiae inhibited growth and aflatoxin production by a. parasiticus. b. linens caused slight inhibition and a. aceti stimulated growth and aflatoxin production by a. parasiticus.1977339094
dichloran-rose bengal medium for enumeration and isolation of molds from foods.overgrowth by spreading molds such as rhizopus and mucor species is a problem with fungal enumeration media used for foods. thirty-one antifungal compounds were surveyed for their ability to selectively inhibit such fungi while allowing growth of mycotoxigenic molds and other species of significance in food spoilage. dichloran (2,6 dichloro-4-nitroaniline) restricted growth of rhizopus stolonifer while allowing satisfactory growth of the other test molds. three rhizopus and mucor species were en ...1979485140
[moulds of bakery dusts (author's transl)].a total of 260 samples from bakery dusts were investigated. the samples were taken in the great part with the sedimentation-method. a large concentration of moulds was found in the meal-room. the fungal flora was here charcterized by species of rhizopus nigricans, mucor and circinella. with a new volumetric sampler a total quantity of 8 680 fungus spores of particles in 1 m3 was registrated. by a re-examination we found 4473. in the baker's rooms besides moulds (aspergillus, penicillium etc.) th ...1977558701
fungal antigens as a source of sensitization and respiratory disease in scottish maltworkers.mycological and serological studies were carried out as part of a survey of respiratory disease in scottish maltworkers. 70% of stained sputum smears from 574 workers showed the presence of higher plant cells and/or myclelia, and the spores of common environmental fungi. penicillium spp. (90%), rhizopus stolonifer (48%) and yeasts (53%) were the dominant fungi in 699 sputum cultures, and showed a similar proportional distribution in 327 samples of grain, malt, culms and dusts from fifty-six malt ...1977589785
inducibility of progesterone hydroxylating enzymes in rhizopus nigricans. 1978642505
molds on vegetables at the time of harvest.the mean numbers of colony-forming units of molds present on vegetables at the time of harvest were in the range of 4.2 x 10(3) to 6.7 x 10(3)/g for all vegetables except cucurbits and asparagus. the numbers were not influenced by cultivars within species, duration of the growing season, distant separation of the growing fields, or elevation above ground. numbers increased with rainfall during either of 3 days before harvest and decreased when the mean daily temperature exceeded 24 degrees c. th ...1978646353
viability of spores after repeated freezing and thawing shocks.survival of spores of the fungus rhizopus nigricans after repeated freezing and thawing was investigated. the cooling rate was 10(4) degrees c/min. dry spores were fully inactive after 32 repeated shocks. about one-half of spores were killed after 8 repetitions. the water content did not change the resistance, swollen spores reacted to shocks much like dry ones. the sensitivity of spores to freezing-thawing shocks increased considerably when the spores changed from the dormant to the active stat ...1978648975
efficacy of some essential oils and their constituents on few ubiquitous molds.six essential oils of mentha arvensis, mentha piperita, anethum sowa, cymbopogon winterianus, nardostachys jatamansi, and commiphora mukul were selected and tested for their efficacy against aspergillus flavus, a. fumigatus, a. sulphureus, mucor fragilis, and rhizopus stolonifer. these oils were fungistatic or fungicidal to one or the other molds, depending upon the concentrations.1978749414
study of atmospheric fungi in a big cereal silo over a period of one year.a quantitative and qualitative study of the atmospheric fungi in a big silo was carried out over a period of one year (april 1973--april 1974). about 6 to 12 petri dishes with czapek medium were exposed for 5 minutes every month at different floors of the silo. the study showed:--a very high number of fungi colonies, reaching as many as 903 in march 1974 (a total of 60 min exposure); the dominant fungus was penicillium which was, however, overpassed in certain months by aspergillus (flavus and f ...1975810877
a possible role of cytochrome p-450 in hydroxylation of progesterone by rhizopus nigricans. 1977843352
a study on fungal radioresistance and sensitivity.lower doses of gamma and x-rays (5 and 1 krad, respectively) stimulated the spore germination and growth of 7 tested fungi. higher doses (500 and 100 krad, respectively) revealed that epicoccum nigrum was the most radioresistant, while alternaria humicola, stemphylium verruculosum, rhizopus nigricans, and cladosporium herbarum were of moderate resistance. aspergillus niger and penicillium oxalicum were the most radiosensitive. protein and polysaccharide synthesis were inhibited in the mycelium d ...1977857505
possible role of solar radiation on the viability of some air fungi in egypt.the high occurrence of alternaria humicola and the moderate occurrence of stemphylium verruculosum, rhizopus nigricans, and epicoccum nigrum in the air of egypt could be correlated to their apparent resistance to solar radiation. cladosporium herbarum, aspergillus niger, and penicillium oxalicum, although highly occurring, were light-sensitive. the miniumum solar radiation in november, coupled with the highest total fungal catch, dominated by cladosporium herbarum, reveals the importance of sola ...19761037050
the 11alpha and 17alpha-progesterone hydroxylases of rhizopus nigricans nrrl 1477.differential induction of cultures of rhizopus nigricans indicated that hydroxylation of progesterone at the 11alpha- and 17alpha-positions is due to two separate enzymes. this is supported by the finding that 11alpha- and 17alpha-hydroxylating activities are separated by differential centrigufation of cell-free extracts. the feasibility of introducing a hydroxyl group at the 11alpha- or 17alpha-position of hydroxylated progesterone derivatives was tested.19751114928
toxigenic fungi in food.forty-five fungal isolates from moldy supermarket foods were tested for toxicity to brine shrimp, and twenty-two of these isolates were subsequently tested for toxicity to chicken embryos. highly toxigenic fungi were cladosporium sphaerospermum from a bakery product, fusarium oxysporum from carrots, f. solani from cabbage, aspergillus niger and penicillium corylophilum from bread, p. cyclopium and p. herguei from corn meal, p. lanosum from onions,p. steckii from chocolate syrup, penicillium sp. ...19751147614
microbiological hydroxylation. part xvi. incubation of derivatives (mainly acetals) of 5alpha-androstane ketones with the fungi calonectria decora, aspergillus ochraceus, and rhizopus nigricans. 19751172504
studies of the invasion of carrot root parenchyma by rhizopus stolonifer lind. 19751186134
microbiological hydroxylation. part xxi. hydroxylations of 3-halogeno-17-oxo-, 3-halogeno-7-oxo-, and 17-halogeno-3-oxo-androstanes by the fungi calonectria decora, rhizopus nigricans, and aspergillus ochraceus. 19751239450
correlation of biocatalytic activity in an organic-aqueous two-liquid phase system with solvent concentration in the cell membrane.results presented here show that loss of progesterone 11 alpha-hydroxylase activity in rhizopus nigricans in aqueous-organic two-liquid phase and cosolvent systems correlates well with the concentration of solvent in the cell membranes. rhizopus nigricans is shown to retain full 11 alpha-hydroxylase activity at saturating aqueous phase concentrations of hexane and the higher primary alcohols. this reflects their inability to attain a critical concentration in the cell membranes. the relationship ...19901366443
a study on antigenic and allergenic changes during storage in three different biological extracts.the stability of three allergens common in tropical countries was evaluated under different storage conditions. prosopis juliflora (pj), rhizopus nigricans (rn), and wheat dust (wd), were taken as representatives of various groups of allergens viz, pollen, fungi and dust. the extracts were stored in buffer containing phenol (0.4%) or glycerol (50%) at temperatures ranging from 4-55 degrees c for 15 to 60 days. protein content of pj extract was reduced remarkably when it was stored at 40 degrees ...19921418181
phenoloxidase production and vanillic acid metabolism by zygomycetes.the ability of 23 strains of zygomycetes to produce extracellular phenoloxidases was examined on solid media by using 10 different reagents. the results varied depending on the reagent and indicated that most of the strains were devoid of phenoloxidase activity. the production of inducible phenoloxidases was demonstrated by the bavendamm reaction. the study of the biotransformation of vanillic acid in synthetic medium indicated that the reaction most often obtained was the reduction of vanillic ...19921602986
[evaluation of allergy to conditionally pathogenic fungi].sensitization to candida albicans, mucor, cladosporium, penicillium, alternaria, rhizopus nigricans was studied in vitro and in vivo in patients suffering from allergic diseases. the overwhelming majority of the positive responses to skin tests were of the immediate type. in parallel with the immediate responses, delayed ones were recorded in some patients. positive responses in radioallergosorbent test and in estimation of the neutrophil injury index according to v. a. fradkin did not always co ...19901705604
thermophilic and thermotolerant fungi of animals' hair.nine thermophilic genera and 17 species in addition to one variety of aspergillus flavus, malbranchea pulchella and humicola grisea were collected from hair samples in riyadh, saudi arabia at 45 degrees c. fifty-one hair specimens of rabbit, sheep, camel and horse were examined for the presence of thermophilic fungi. the most frequent species were aspergillus fumigatus, aspergillus niger, thermoascus aurantiacus and malbranchea pulchella var. sulfurea. in low frequency, aspergillus flavus, asper ...19911805498
localization of the gene encoding steroid hydroxylase cytochrome p-450 from rhizopus nigricans inside a hindiii fragment of genomic dna.the gene encoding steroid inducible cytochrome p450 of rhizopus nigricans atcc 6227b has been found inside a hindiii fragment of the genomic dna by hybridization with a partial length cdna probe. the latter was isolated by immunoscreening a cdna library prepared in the lambda gt11 expression system and identified on the basis of inducibility and sequence analysis. the nucleotide sequence of the cdna probe revealed a coding sequence for the heme binding segment characteristic of the p450 gene fam ...19911872831
induction of steroidal 11 beta-hydroxylase of cochliobolus lunatus.the induction of steroidal 11 beta-hydroxylase of cochliobolus lunatus was studied and the effect of the structure of steroid inducers and additives on the extent of enzyme induction determined. 21-hydroxyprogesterone was found to be the best inducer and torlak peptone 1 the best additive. a certain parallelism was found between the induction of 11 beta-hydroxylase of cochliobolus lunatus and 11 alpha-hydroxylase of rhizopus nigricans.19911997119
detection of chitin deacetylase activity after polyacrylamide gel electrophoresis.mucor racemosus and rhizopus nigricans were used as sources of chitin deacetylases. crude protein extracts were subjected to polyacrylamide gel electrophoresis at ph 8.9 (davis system) or 4.3 (reisfeld system) under native conditions. after electrophoresis, an overlay gel containing 0.1% (w/v) glycol chitin as substrate was incubated in contact with the separation gel. chitin deacetylase activity was revealed by uv illumination with a transilluminator after staining for 5 min in 0.01% (w/v) calc ...19902281870
immunochemical investigation of allergens from rhizopus nigricans.the allergenic proteins of mould, rhizopus nigricans extract (rne) were identified and characterized by crossed immunoelectrophoresis (cie), thin-layer isoelectrofocusing (tlief) and rast inhibition. cie revealed that the extract contained at least 31 distinct antigens. on tlief the extract resolved into 22 bands in pi 3.5-6.8. two important allergens, rhiz iiib and vib were purified by a combination of ammonium sulfate precipitation, anion exchange chromatography on deae-sephadex column and gel ...19902288393
progesterone side-chain degradation beside hydroxylation with rhizopus nigricans depends on the presence of nutrients.in the absence of nutrients, rhizopus nigricans transforms progesterone into a mixture of 11 alpha-hydroxy-4-androstene-3,17-dione and 11 alpha-hydroxy-1,4-adrostadiene-3,17-dione. the same mixture is obtained by the transformation of testosterone and its acetate.19902308327
11 beta-hydroxylation of steroids by cochliobolus lunatus.the substrate specificity of 11 beta-hydroxylase of cochliobolus lunatus was studied and a close parallelism to the results obtained with 11 alpha-hydroxylase of rhizopus nigricans was observed. it was found that the cell wall does not differentiate between the steroid substrates used and the absence of the cell wall increases the bioconversion.19902355739
factors affecting the induction of 11 alpha-hydroxylase of progesterone in the filamentous fungus rhizopus nigricans.the 11 alpha-hydroxylase of progesterone was induced in the filamentous fungus rhizopus nigricans atcc 6227b with different steroids as inducers and the induction process was optimized in regard to the age of the mycelium, to the concentration of the inducer and to the time of induction. deoxycorticosterone and testosterone, steroids with higher polarity of the side-chain than progesterone, although poorer substrates for in vivo hydroxylation than progesterone, induced more enzyme compared to pr ...19902362437
survey of the mycoflora and mycotoxins of cotton seeds and cotton seed products in egypt.thirty-nine species and 16 fungal genera were isolated from egyptian cotton seeds, cotton seed meal and cotton seed cake on 1% glucose-czapek's agar medium incubated at 28 degrees c. aspergillus was the most frequent genus and it emerged in 87-100% of the samples contributing 70-98% of total fungi in the three substrates tested. the most common species were a. niger, a. flavus, a. fumigatus, a. terreus and rhizopus stolonifer; a. niger, a. fumigatus and penicillium corylophilum; and a. niger, a. ...19902388680
[reactivity of human lymphocytes to yeast-like and mold fungi].the capacity of the allergens of mold fungi (rhizopus nigricans, mucor pusillus, alternaria tenuis, cladosporum herbarum, fusarium oxysporum) and yeast-like fungi (candida albicans) to induce the production of lymphokins by human lymphocytes was studied. all these preparations were active in reactions with lymphocytes obtained from adult donors, but did not activate lymphocytes of newborns (obtained from umbilical blood). in equal doses (10 micrograms/ml) c. albicans allergen was more active tha ...19892500001
mycoflora of anise and fennel seeds in egypt.using four medium types (glucose-, cellulose-, 50% sucrose- and 10% nacl-czapek's agar), it was possible to isolate 15 fungal genera, 78 species and 6 varieties. the collective fungal spectrum varied from one medium to another where the highest number of species (57 species/1000 seeds) was obtained on glucose- and the lowest (31 species/1000 seeds) on 10% nacl-czapek's agar. aspergillus, penicillium, and sometimes rhizopus and chaetomium were the most common genera on the different medium types. ...19892600777
fungal flora of poultry feedstuff ingredients.one hundred and ten samples representing five types of poultry feed ingredients were mycologically examined. these samples included soybean meal, ground maize, cotton-seed cake, wheat bran and fish meal (22 samples each). among the 73 mesophilic fungal species, aspergillus flavus, a. niger and a. fumigatus were the most dominant. a. terreus, a. flavipes, mucor circinelloides, scopulariopsis brevicaulis, penicillium chrysogenum, fusarium moniliforme and rhizopus stolonifer were found to be common ...19892621568
hydroxylation of steroids with nonpolar side chains with 11 alpha-hydroxylase of rhizopus nigricans.steroids with nonpolar side chains with 2, 4 and 8 c atoms were used as substrates for the 11 alpha-hydroxylase of rhizopus nigricans. their bioconversion was compared to that of progesterone, which was found to be far the best substrate giving the highest total bioconversion. 3-keto-4-ene steroids with nonpolar side chains were converted to their hydroxylated products in a small yield or not at all. the absence of an oxygen function in the side chain did not affect the regio-specificity of the ...19892788778
mycoflora and mycotoxin-producing fungi of air-dust particles from egypt.using the dilution-plate method, 27 genera and 64 species were collected from 20 air-dust samples on glucose - (24 genera and 57 species) and cellulose - (21 genera and 45 species) czapek's agar at 28 degrees c. there are basic similarities between the mycoflora of air-dust on the two media and the most prevalent species were aspergillus niger, a. flavus, a. ochraceus, a. terreus, a. versicolor, penicillium chrysogenum, p. funiculosum, alternaria alternata, cladosporium herbarum, fusarium oxyspo ...19862938009
microorganisms associated with mouldiness of dried yam chips and their prevention.the broad objective of this study was to isolate and identify the microorganisms causing mouldiness of stored yam chips and to look for ways of preventing the problem. microorganisms isolated included aspergillus flavus, a. glaucus, a. nidulans, a. niger, a. ochraceous, a. tamarii, a. candidus, penicillium oxalicum, trichoderma longibrachyatum, rhizopus nigricans, cylindrocarpon radicicola, neurospora crassa, botryodiplodia theobromae, bacillus subtilis, bacillus cereus, erwinia carotovora and s ...19883231261
effect of herbicides on growth of some microscopic soil fungus species.the effect of 14 herbicides and two herbicide combinations of three microscopic soil fungus species was investigated by miller's method. (i) none of the 14 herbicides and 2 combinations belonging to four derivative groups induced the growth of aspergillus niger, fusarium oxysporum and rhizopus nigricans; (ii) higher doses of the herbicides prevented the growth of all test organisms significantly, the triasin derivative hungazin pk being the less and tiocarbamate derivatives alirox b 80 ec, aneld ...19883245414
hydroxylation of steroids with 11 alpha-hydroxylase of rhizopus nigricans.three groups of 3-keto-4-ene steroids with different side chains were used as substrates for the induced 11 alpha-hydroxylase of rhizopus nigricans. the highest total bioconversion as well as the highest yield of 11 alpha-hydroxylated product is found using progesterone as substrate. by changing the polarity of the side chain, much higher yields of 6 beta- and 7 beta-hydroxylated products relative to 11 alpha-hydroxylated product are obtained. our results thus provide evidence for the importance ...19873498094
mycoflora and vitamin content of sun-dried food condiments in nigeria.the fungi most frequently isolated (of 20-100% incidence) from fresh okra, pepper fruits and melon seeds are botryodiplodia theobromae, rhizopus stolonifer, trichoderma harzianum, mucor mucedo and fusarium oxysporum. the major mycoflora of the fruits which had been sun-dried for twenty days are comprised of aspergillus spp and penicillium spp which initially had formed the minor components (of less than 20% incidence) of the colonising population. the effect of sun-drying on the fruits was a sta ...19873507682
resolution and reconstitution of cytochrome p-450 containing steroid hydroxylation system of rhizopus nigricans.11 alpha-hydroxylation of progesterone in the eucaryotic filamentous fungus rhizopus nigricans is catalyzed by a monooxygenase. three components of this multienzyme system, cytochrome p-450, rhizoporedoxin and a fad containing rhizoporedoxin reductase have been separated from the postmitochondrial fraction on deae cellulose. using nadph as electron donor we showed that the presence of all three components was necessary for the reconstitution of the active electron transport chain.19873586666
antibiotic activity of the pyrenocines.pyrenocine a, a phytotoxin produced by pyrenochaeta terrestris (hansen) gorenz, walker and larson, possesses general antibiotic activity against plants, fungi, and bacteria. effective doses for 50% inhibition (ed50s) are 4 micrograms/ml for onion seedling elongation; 14, 20, 20, and 25 micrograms/ml for the germination of asexual spores of fusarium oxysporum f. sp. cepae, fusarium solani f. sp. pisi, mucor hiemalis, and rhizopus stolonifer, respectively. pyrenocine a also inhibits the linear myc ...19873594310
resolution and reconstitution of the nadph-cytochrome c (p-450) reductase induced by progesterone in rhizopus nigricans.the nadph-cytochrome c (p-450) reductase induced in the filamentous fungus rhizopus nigricans as a component of 11 alpha-hydroxylase of progesterone was resolved by deae-cellulose chromatography into two components. one of the components is an iron-sulfur protein (rhizoporedoxin), whereas the other component is a protein with reductase activity dependent on nadph (rhizoporedoxin reductase). as shown in the reconstitution assay, the nadph-cytochrome c (p-450) reductase activity was restored upon ...19853936501
casbene synthetase: regulation of phytoalexin biosynthesis in ricinus communis l. seedlings. purification of casbene synthetase and regulation of its biosynthesis during elicitation.castor bean (ricinus communis l.) seedlings responded to stress by producing the antifungal diterpene, casbene. casbene synthetase, the enzyme catalyzing the production of casbene from geranylgeranyl pyrophosphate, was purified 4700-fold to a final specific activity of 4.2 nkat/mg protein by a combination of ion-exchange and dye-ligand chromatographic procedures. approximately 500 micrograms of purified enzyme was recovered from 1600 seedlings that had been infected with the fungus, rhizopus sto ...19853985625
influence of phosphate compounds on certain fungi and their preservative effects on fresh cherry fruit (prunus cerasus, l.).studies were conducted to ascertain the retarding effects of four phosphate compounds (sodium hexametaphosphate, sodium tripolyphosphate, sodium tetraphosphate, and tetrasodium pyrophosphate) on molding of fresh cherries (prunus cerasus, l.). in vitro studies on their antimycotic effects against the most common fungal spoilers, penicillium expansum, rhizopus nigricans, and botrytis sp., were also carried out. sodium tetraphosphate appeared to be the most effective compound in preserving cherries ...19684295176
purification and properties of rna polymerases i and ii from germinated spores of rhizopus stolonifer. 19744420468
[rhizopus nigricans ehr. action of various physical factors on the weight growth of the mycelium and on uv absorption spectra of culture filtrates]. 19744433134
synthesis of ribonucleic acids during the germination of rhizopus stolonifer sporangiospores. 19744435301
[effect of the number of methyl groups in the progesterone molecule on its hydroxylation by rhizopus nigricans cultures]. 19744444567
translocation of s 35 in rhizopus stolonifer. 19724556581
characteristics of deoxyribonucleic acid polymerase isolated from spores of rhizopus stolonifer.deoxyribonucleic acid (dna)-dependent dna polymerase was purified several hundredfold from germinated and ungerminated spores of the fungus rhizopus stolonifer. the partially purified enzymes from both spore stages exhibited identical characteristics; incorporation of [(3)h]deoxythymidine monophosphate into dna required mg(2+), dna, a reducing agent, and the simultaneous presence of deoxyguanosine triphosphate, deoxycytidine triphosphate, and deoxyadenosine triphosphate. heat-denatured and activ ...19734728271
microbiological hydroxylation of steroids. vii. the pattern of dihydroxylation of mono-oxo-5 alpha-androstanes and 5 alpha-estranes with the fungus rhizopus nigricans. 19734739028
microbiological hydroxylation of steroids. 8. the pattern of monohydroxylation of diketones and keto-alcohols derived from 5 alpha-androstane with cultures of the fungus, rhizopus nigricans. 19734739029
lomasome development in rhizopus stolonifer sporangiospores during anaerobiosis. 19734752340
[effect of the incubation temperature on the growth and spore formation of penicillium italicum and rhizopus nigricans treated with ionizing radiations]. 19734777355
physiological and morphological correlation of rhizopus stolonifer spore germination.sporangiospores of rhizopus stolonifer were examined at various stages of germination by scanning electron and phase-contrast microscopy. these observations were correlated with changes in spore dry weight, spore volume, respiration, and syntheses of ribonucleic acid, deoxyribonucleic acid, and protein during germination.19744811549
ultrastructural details in germinating sporangiospores of rhizopus stolonifer and rhizopus arrhizus.electron microscope examination of sporangiospore sections from rhizopus stolonifer (ehrenb. ex fr.) lind. and r. arrhizus fischer revealed details on intracellular organization not previously reported. aldehyde fixation followed by chromeosmium postfixation permitted clear depiction of ribosomes hitherto unrevealed in these cells. mitochondria were diversiform. spore wall structures in the two species were generally similar, but outer contours differed sufficiently to permit easy species identi ...19684876136
[hydroxylation of progesterone by rhizopus nigricans]. 19694981103
[hydroxylation of progesterone by rhizopus nigricans in the presence of chloramphenicol]. 19704986691
changes in soluble ribonucleic acid polymerases associated with the germination of rhizopus stolonifer spores. 19725043713
protein synthesis during fungal-spore germination. vi. analysis of transfer ribonucleic acid from germinated and ungerminated spores of rhizopus stolonifer. 19725070713
studies on fungal polysaccharides. ix. the acidic polysaccharide from the cell wall of rhizopus nigricans. 19715145919
[determination of the bacterial motility rate by cultivation with rhizopus nigricans]. 19715146296
[rhizopus nigricans ehrenberg. studies on its nitrogen nutrition; correlative study of the ponderal growth of the mycelium, of the media ph and of the spectrum of culture filtrates as a function of time]. 19715149948
the in vitro transformation of progesterone by rhizopus nigricans ref 129. 19715160388
pyruvate carboxylase of rhizopus nigricans and its role in fumaric acid production. 19695349282
protein synthesis during fungal spore germination. iv. transfer ribonucleic acid from germinated and ungerminated spores.transfer ribonucleic acid (trna) fractions isolated from germinated and ungerminated spores of botryodiplodia theobromae and rhizopus stolonifer had acceptor activity for all 20 amino acids commonly found in protein, when tested with an enzyme fraction from germinated spores. accordingly, it is unlikely that the absence of trna for a particular amino acid limits protein synthesis in fungal spores.19695364287
microbiological transformations. i. hydroxylation of progesterone at c-11 by rhizopus nigricans and penicillium oxalicum. 19695380069
transformation of progesterone by aspergillus niger 100 and rhizopus nigricans ref, 129. 19705420621
[method for determination of bacterial mobility by culture on rhizopus nigricans]. 19705426400
transformation of progesterone by rhizopus nigricans ref 129 as influenced by modification of the fermentation medium. 19705460205
hemolytic activity of rhizopus nigricans and rhizopus arrhizus. 19705466029
preliminary characterization of the hemolysin of rhizopus nigricans. 19705466030
acidic polysaccharides from the cell wall of absidia cylindrospora, mucor mucedo, and rhizopus nigricans. 19705471789
[rhizopus nigricans ehrenberg. first results of the physico-chemical and biological study of a culture filtrate]. 19705500091
[effect of some cultivation conditions on the ability of mucor fungi tieghemella hyalospora and rhizopus nigricans to effect 11 alpha-hydroxylation of steroid molecules]. 19715567625
formation and regeneration of protoplasts in the mold rhizopus nigricans. 19685672584
ultrastructural changes in rhizopus stolonifer sporangiospores in response to anaerobiosis.rhizopus stolonifer sporangiospores developed prominent ultrastructural changes under anoxia. mitochondria were scattered randomly throughout the cytoplasm in spores incubated aerobically for 3 hr, but moved to the periphery of the cytoplasm when the spores were exposed to anoxia. endoplasmic reticulum, inconspicuous in control spores, appeared near the plasmalemma and was frequently found connected to a nuclear membrane. the cytoplasm, otherwise usually uniformly dense and containing abundant r ...19695784225
organization of enzymes in the common aromatic synthetic pathway: evidence for aggregation in fungi.centrifugation in sucrose density gradients of partially purified extracts from six species of fungi, i.e., rhizopus stolonifer, phycomyces nitens, absidia glauca (phycomycetes), aspergillus nidulans (ascomycetes), coprinus lagopus, and ustilago maydis (basidiomycetes), indicate that the five enzymes catalyzing steps two to six in the prechorismic acid part of the polyaromatic synthetic pathway sediment together. the sedimentation coefficients for these enzymes are very similar in the six specie ...19695802608
inactivation of rhizopus stolonifer sporangiospores by single and combined treatments of heating, chilling, and gamma-irradiation. 19695821201
fungistatic effects of controlled atmospheres.the fungistatic effects of controlled atmospheres composed of increased co(2) and decreased o(2) was studied in a manner such that the condition of stored fruit was not a factor in the growth of the fungi. varying concentrations of o(2) and co(2) were used. the fungi used were botrytis alli, rhizopus nigricans, and penicillium expansum. the results showed that controlled atmospheres, within the limits of concentrations usable for fruit storage, are effective fungistatic agents.19665951331
ultrasound and the ultramicroscopic structure of rhizopus nigricans. 19665990081
effects of chemical protection on repair of potentially lethal irradiation injury in rhizopus stolonifer sporangiospores. 19676019779
mechanism of fumaric acid accumulation in rhizopus nigricans.it is doubtful that the glyoxylate bypass plays a significant role in the accumulation of fumaric acid by fungi, as has been postulated. in high glucose media, which favor fumarate production, isocitrate lyase (threo-d(s) isocitrate glyoxylate lyase), which is the key enzyme of the glyoxylate bypass, is strongly repressed. the specific activity of this enzyme remains low as long as glucose is present in the medium, even though fumarate formation proceeds at a high level. in addition, the activit ...19676020565
control of malate synthase formation in rhizopus nigricans.the control of malate synthase formation in a fumaric acid-producing strain of rhizopus nigricans has been found to be similar in most respects to that of isocitrate lyase, the companion enzyme of the glyoxylate bypass. a basal level is formed in a casein hydrolysate medium, which is repressed by glucose. utilization of glucose during growth results in relief of glucose repression. any factor which stimulates growth promotes relief of glucose repression by enhancing the incorporation of represso ...19676074401
substrate effect on 2,3-butylene glycol production by rhizopus nigricans and penicillium expansum.rhizopus nigricans and penicillium expansum produced 2,3-butylene glycol which accumulated in natural and artificial media with time. mycelial mats of p. expansum decreased the quantity of a diacetyl substrate and converted part of this substrate into acetylmethylcarbinol (amc) and 2,3-butylene glycol. mycelial mats of p. expansum also decreased amc substrate with the formation of 2,3-butylene glycol. 2,3-butylene glycol decreased slightly during incubation with the fungal mat. the formation of ...19676080717
solubilization and separation of microsomal cytochrome p-450 and nadph-cytochrome c reductase of rhizopus nigricans. 19836408312
d-homoandrostanes. 4. the incubation of some d-homo-5 alpha-androstanes with rhizopus nigricans.nine dioxygenated d-homoandrostanes were incubated with rhizopus nigricans to investigate the effect of d-ring modification on microbiological hydroxylation. structure determination of the products by nmr spectroscopy, and in certain cases independent synthesis of their oxidised products, showed that in contrast to 5 alpha-androstanes the majority of the compounds were hydroxylated in the "reverse" mode, and only d-homo-5 alpha-androstane-3,17-dione was hydroxylated in the "normal" mode to any e ...19836658861
composition of the fungal flora of four cereal grains in saudi arabia.using the grain-plate method and on glucose- czapek 's agar at 28 degrees c, fifty-eight species belonging to 26 genera were collected from barley (42 species and 19 genera), maize (29 species and 16 genera), sorghum (32 species and 17 genera) and wheat grains (42 species and 18 genera). the most frequent genera were aspergillus, penicillium, rhizopus, fusarium, and mucor followed by alternaria, drechslera , and curvularia. from the preceding genera aspergillus flavus, a. niger, penicillium nota ...19846727980
inducibility of cytochrome p-450 and of nadph-cytochrome c reductase in progesterone treated filamentous fungi rhizopus nigricans and rhizopus arrhizus. 19816785529
aflatoxin and aflatoxicosis. i. fungal flora of some food and animal feeds with special references to aflatoxin-producing abilities.a wide range of fungi, amounting to fifty-six species belonging to twenty-two genera, have been recovered from animal feeds and foodstuffs. the most frequent fungi were aspergillus niger, and a. flavus, followed by mucor racemosus, alternaria alternata. rhizopus stolonifer, penicillium corylophilum and p. notatum. three genera were found to be of moderate occurrence, namely, mucor, rhizopus and alternaria. the three following genera were of low occurrence: cladosporium, fusarium, and neurospora. ...19827070483
ultrastructure of spores of rhizopus nigricans after repeated freezing and thawing shocks.disintegration of nuclear envelopes is the only ultrastructural change detectable by freeze-etching in dormant spores of the mould rhizopus nigricans, both dry and swollen, subjected to repeated freezing and thawing. the increase of the number of freeze-inactivated spores corresponds well with the increase of the number of damaged nuclei. this fact led us to formulate a hypothesis that the structure of the nucleus is the primary target of the freezing or thawing damage. as other biomembranes are ...19807399373
studies on fungi associated with tomato fruits and effectiveness of some commercial fungicides against three pathogens.among 39 fungal species and one variety belonging to 16 genera isolated from 116 healthy tomato fruits collected from markets in assiut, egypt, during 1994, aspergillus niger was found to be the most prevalent, being isolated from 84.6% of the samples. of 11 species recovered from 156 diseased tomatoes, alternaria alternata, rhizopus stolonifer and a. niger were the most common and isolated from 52.7%, 35.9% and 25.0% of the samples, respectively. experiments for comparison of the effects of med ...19957566057
contribution of selected fungi to the reduction of cyanogen levels during solid substrate fermentation of cassava.the effect of six individual strains of the dominant microflora in solid substrate fermenting cassava on cyanogen levels was examined. six out of eight batches of disinfected cassava root pieces were incubated for 72 h after inoculation with either of the fungi geotrichum candidum, mucor racemosus, neurospora sitophila, rhizopus oryzae and rhizopus stolonifer, or a bacillus sp., isolated from on-farm fermented cassava flours from uganda. one non-inoculated batch was incubated as a reference. lev ...19957577362
the role of cytochrome p450(11 alpha) in detoxification of steroids in the filamentous fungus rhizopus nigricans.the evidence was presented that steroid hydroxylating enzyme complex induced by substrate in the filamentous fungus rhizopus nigricans (r. nigricans) alleviated toxic effect(s) of the steroid on fungal growth. the growth inhibition of fungal mycelium observed in steroid-containing culture(s) became much more obvious when fungal mycelia were grown in the simultaneous presence of inducing steroid and the p450(11 alpha) inhibitor metyrapone. on the other hand, in experiments where we followed the f ...19957696148
synthesis of enantio-manoyl oxides: modifiers of the activity of adenylatecyclase enzyme.cyclization of methyl ent-8 alpha-hydroxylabd-13(16),14-dien-18-oate with m-chloroperbenzoic acid gave methyl (13s)-ent-16-hydroxy-8 alpha,13-epoxylabd-14-en-18-oate and its epimer at c-13. biotransformation of the former (which exhibits antileishmania activity) with rhizopus nigricans cultures produced the methyl (13s)-ent-11 beta,16-dihydroxy-8 alpha,13-epoxilabd-14-en-18-oate (carbomanoyl, which inhibits the activity of the adenylatecyclase enzyme), methyl (13s)-ent-3 beta,16-dihydroxy-8 alph ...19957772300
investigation on the toxicity of fungi from rootstock snacks.chicken embryo bioassay was used to monitor the toxicity of extracts from rootstock snack samples during a 210-day storage period. results show that the relative toxicity values which were initially very low increased significantly as from 120th day (when 32% mortality was recorded) up till the last day when 73% was obtained. toxicity of extracts from axenic cultures of 12 fungal species isolated from the snack samples was also determined. the strains of aspergillus chevalieri, rhizopus nigrican ...19948145803
fungal flora and mycotoxins of six kinds of nut seeds for human consumption in saudi arabia.a wide range of moulds representing several genera and species, was recorded in this study from 5 seed samples of each almond, cashew nut, chestnut, hazelnut, pistachio nut and walnut collected from different markets in ar' ar, saudi arabia. the total counts of fungi were widely fluctuated between 1960-7704 and 1948-7434 colonies/g dry seeds on glucose-czapek's and glycerol agar media at 28 degrees c, respectively, and represented twenty genera, 53 species and 2 varieties of fungi. the prevalent ...19938159218
filamentous fungi and mycotoxin detected in coconut.fifty-nine species and one variety belonging to 25 genera of fungi were isolated from 25 coconut samples on glucose-czapek's (25 genera and 55 species + 1 variety) and dichloran-glycerol (8 genera and 32 species + 1 variety) agar media at 28 degrees c. the common fungi on both media used were aspergillus flavus, a. niger, penicillium chrysogenum and cladosporium cladosporioides. on glucose-czapek's agar, a. flavus var. columnaris, p. oxalicum, alternaria alternata, rhizopus stolonifer and tricho ...19938212938
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