Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| extracellular production of alpha-rhamnosidase by rhizopus nigricans. | extracellular production of alpha-rhamnosidase [ec 3.2.1.40] from an indigeneous fungal strain of r. nigricans has been demonstrated. the enzyme has been shown to follow michaelis-menten kinetics using p-nitrophenyl-alpha-l-rhamnopyranosid as a substrate. the ph and the temperature optima of the enzyme have been found to be around 6.5 and 60 degrees-80 degrees c respectively. | 1995 | 8557313 |
| degradation of stachyose, raffinose, melibiose and sucrose by different tempe-producing rhizopus fungi. | forty-six strains of tempe-forming rhizopus species were screened for their ability to grow on raffinose as the sole carbon source. six of the strains showed good growth and sporulation. these isolates were one rhizopus oligosporus, one rhizopus microsporus var. chinensis, three rhizopus oryzae and one rhizopus stolonifer. these six moulds and r. oligosporus strain nrrl 2710 were investigated for their metabolism of the raffinose family of alpha-galactoside carbohydrates. degradation experiments ... | 1995 | 8579835 |
| transmission of the effect of an antifungal agent within a single hypha. | a micro-compartment culture method was devised in which a single hypha of rhizopus stolonifer growing on an agar section traversed an antifungal non-diffusible barrier to another agar section; thus the local environment of the distal or proximal part of the hypha could be controlled independently. the responses in terms of hyphal extension of the test fungus to local application of amphotericin b in this culture system were estimated by using an automatic analysing system. after hyphae had trave ... | 1995 | 8597551 |
| 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 ... | 1995 | 7566057 |
| 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 ... | 1995 | 7577362 |
| 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 ... | 1995 | 7696148 |
| 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 ... | 1995 | 7772300 |
| a streptomyces chitosanase is active in transgenic tobacco. | growth inhibition towards rhizopus nigricans, fusarium oxysporum f. sp. radicis-lycopersici, verticillium albo-atrum and pythium ultimum was observed in vitro using a purified chitosanase from an actinomycete, streptomyces sp, strain n174. the corresponding gene, with its own signal peptide, was inserted into pbi121.7 shuttle vector to transform tobacco. transgenic plants were analysed for chitosanase activity by a sodium dodecyl sulfate-polyacrylamide gel electrophoresis assay. two major and on ... | 1995 | 24185780 |
| 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 ... | 1994 | 8145803 |
| 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 ... | 1993 | 8159218 |
| 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 ... | 1993 | 8212938 |
| survey of mycoflora and mycotoxins in egyptian soybean seeds. | after four months in commercial storage, 100 soybean samples from different places of egyptian governorates were assayed for filamentous fungal growth at two incubation temperatures (28 and 45 degrees c). 73 species and 8 varieties belonging to 32 genera were isolated by the dilution plate method. at 28 degrees c, the common species were aspergillus flavus, a. fumigatus, a. niger and a. alutaceus, followed by a. terreus, penicillium chrysogenum, p. citrinum, mucor hiemalis, m. racemosus, emerice ... | 1993 | 8271157 |
| comparison of methods for estimating the biomass of three food-borne fungi with different growth patterns. | to evaluate the effectiveness of steps taken to reduce the growth of molds in food and feed, methods that can accurately quantify the degree of fungal contamination of solid substrates are needed. in this study, the ergosterol assay has been evaluated by comparing the results of this assay with spore counts and hyphal length measurements made with a microscope and with cfu counts. three fungi with different growth patterns during cultivation on a synthetic agar substrate were used in these exper ... | 1993 | 8434921 |
| optimization of medium for extracellular nuclease formation from rhizopus stolonifer. | a strain of rhizopus stolonifer produced a high activity of extracellular dnaase when grown on ypg (yeast extract peptone glucose) medium. the source of peptone had a marked effect on the enzyme yield and only one peptone (i.e. from sarabhai m. chemicals ltd, india) supported enzyme production. maximum enzyme activity (88 u/ml) was obtained after 4 days' growth under submerged conditions in ypg medium containing 100 μm mn(2+), co(2+) or mg(2+), and glucose as the sole carbon source. the unpurifi ... | 1993 | 24419948 |
| steroid 11ß-hydroxylation by a fungal microsomal cytochrome p450. | the steroid 11ß-hydroxylase activity of the fungus cochliobolus lunatus was increased about 100-fold by cultivation of mycelia for 4-5 h with 20-hydroxymethyl-1,4-pregnadien-3-one. cell-free extracts revealed a maximum activity of 45 nmol 11ß-hydroxyprogesterone/h·mg protein in the 100,000 g pellet fraction. the 11ß-hydroxylation was dependent on nadph. the formation of 11ß-hydroxyprogesterone correlated linearly with the cytochrome p450 concentration. the fungal 11ß-hydroxylase transformed both ... | 1992 | 22217857 |
| 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 ... | 1992 | 1418181 |
| 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 ... | 1992 | 1602986 |
| 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 ... | 1991 | 1805498 |
| 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 ... | 1991 | 1872831 |
| 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. | 1991 | 1997119 |
| fermentation of millet to produce kamu a nigerian starch-cake food. | microorganisms present in the unfermented grains of millet at the initial stage of steeping and after sieving at the initial stage of souring for the preparation of kamu were moulds (aspergillus versicolor, penicillim nigricans and rhizopus stolonifer), bacteria (pediococcus pentosaceus and lactobaclllus plantarum) and a yeast (saccharomyces cerevisiae). only the bacteria and yeast persisted to the end of the steeping period. these, together with another yeast, candida krusel, brought about the ... | 1991 | 24424932 |
| effect of apiforol and apigeninidin on growth of selected fungi. | selected fungi were grown on agar plates in the presence of naringenin, apiforol, apiforol 7-o-rhamnoglucoside, or apigeninidin. of the four compounds tested, only apigeninidin inhibited the growth offusarium oxysporum, gibberella zeae, gliocladium roseum, altemaria solani, and phytophthora infestons. in contrast, the growth ofrhizoctonia solani, sclerotium rolfsii, and rhizopus stolonifer (- and +) was not effected by any compound. since apigeninidin is present in seeds ofsorghum sp., we hypoth ... | 1991 | 24258604 |
| 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 ... | 1990 | 2281870 |
| 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 ... | 1990 | 2288393 |
| 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. | 1990 | 2308327 |
| 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. | 1990 | 2355739 |
| 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 ... | 1990 | 2362437 |
| 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. ... | 1990 | 2388680 |
| [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 ... | 1990 | 1705604 |
| 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 ... | 1990 | 1366443 |
| [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 ... | 1989 | 2500001 |
| 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. ... | 1989 | 2600777 |
| 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 ... | 1989 | 2621568 |
| 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 ... | 1989 | 2788778 |
| 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 ... | 1988 | 3231261 |
| 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 ... | 1988 | 3245414 |
| 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 ... | 1987 | 3498094 |
| 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 ... | 1987 | 3507682 |
| 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. | 1987 | 3586666 |
| 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 ... | 1987 | 3594310 |
| 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 ... | 1986 | 2938009 |
| biosynthesis of the macrocyclic diterpene casbene in castor bean (ricinus communis l.) seedlings : changes in enzyme levels induced by fungal infection and intracellular localization of the pathway. | casbene is a macrocyclic diterpene hydrocarbon that is produced in young castor bean (ricinus communis l.) seedlings after they are exposed to rhizopus stolonifer or other fungi. the activities of enzymes that participate in casbene biosynthesis were measured in cell-free extracts of 67-hour castor bean seedlings (a) that had been exposed to r. stolonifer spores 18 hours prior to the preparation of extracts, and (b) that were maintained under aseptic conditions throughout. activity for the conve ... | 1986 | 16664817 |
| biosynthesis of the macrocyclic diterpene casbene in castor bean (ricinus communis l.) seedlings : the purification and properties of farnesyl transferase from elicited seedlings. | farnesyl transferase (farnesyl pyrophosphate: isopentenyl pyrophosphate farnesyl transferase; geranylgeranyl pyrophosphate synthetase) was purified at least 400-fold from extracts of castor bean (ricinus communis l.) seedlings that were elicited by exposure for 10 h to rhizopus stolonifer spores. the purified enzyme was free of isopentenyl pyrophosphate isomerase and phosphatase activities which interfere with prenyl transferase assays. the purified enzyme showed a broad optimum for farnesyl tra ... | 1986 | 16664818 |
| effect of shear on membrane-associated enzymes: studies of isolated progesterone 11alpha-hydroxylase complex from rhizopus nigricans. | 1985 | 18553636 | |
| effect of shear on membrane-associated enzymes: studies of the release of intracellular protein and of the progesterone 11alpha-hydroxylase complex from rhizopus nigricans. | rhizopus nigricans atcc 6227b grown in either shake flasks or a fermentor was sheared in a concentric cylinder viscometer. the cells grown in shake flasks were found to be more susceptible to disruption by shear than those grown in the fermentor. cells resuspended in a medium containing reduced glutathione and edta were found to be more easily disrupted than cells resuspended in 0.5% nacl. the optimum condition for disruption of shake flask cells grown in the former medium with retention of prog ... | 1985 | 18553637 |
| 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 ... | 1985 | 3936501 |
| 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 ... | 1985 | 3985625 |
| 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 ... | 1984 | 6727980 |
| characteristics of galacturonic acid oligomers as elicitors of casbene synthetase activity in castor bean seedlings. | partial digestion of polygalacturonic acid with polygalacturonase isolated from rhizopus stolonifer produces a mixture of alpha-1,4-d-galacturonide oligomers which act to elicit casbene synthetase activity in castor bean (ricinus communis l). these oligomers were separated by anion exchange chromatography on deae sephadex a-25 into discrete sizes and their degrees of polymerization were analyzed by fast atom bombardment mass spectrometry. a minimum degree of polymerization of nine units appears ... | 1984 | 16663547 |
| comparison of proteinase inhibitor-inducing activities and phytoalexin elicitor activities of a pure fungal endopolygalacturonase, pectic fragments, and chitosans. | rhizopus stolonifer endopolygalacturonase, an elicitor of casbene synthetase activity in castor bean seedlings, was found to be a potent elicitor of the phytoalexin pisatin in pea pods and of proteinase inhibitor i in tomato leaves. the enzyme was an active elicitor or inducer only in its active native state; heat-denatured enzyme was inactive in all three systems. the activities of (a) the tomato pectic polysaccharide proteinase inhibitor-inducing factor, (b) a partially acid hydrolyzed protein ... | 1984 | 16663934 |
| solubilization and separation of microsomal cytochrome p-450 and nadph-cytochrome c reductase of rhizopus nigricans. | 1983 | 6408312 | |
| 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 ... | 1983 | 6658861 |
| 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. ... | 1982 | 7070483 |
| elicitation of casbene synthetase activity in castor bean : the role of pectic fragments of the plant cell wall in elicitation by a fungal endopolygalacturonase. | endopolygalacturonase isolated from culture filtrates of the fungus rhizopus stolonifer was shown previously to act as an elicitor of biosynthetic capacity for the antifungal agent, casbene, in castor bean (ricinus communis l.) seedlings (s.-c. lee, c.a. west 1981 plant physiology 67:633-639). selective amidation of exposed carboxyl groups of the pure fungal endopolygalacturonase using intermediate activation with a water-soluble carbodiimide under mild conditions leads to inactivation of its en ... | 1982 | 16662367 |
| polygalacturonase from rhizopus stolonifer, an elicitor of casbene synthetase activity in castor bean (ricinus communis l.) seedlings. | apparently homogeneous polygalacturonase-elicitor purified from the filtrates of rhizopus stolonifer cultures stimulates germinating castor bean seedlings to produce greatly increased levels of casbene synthetase activity. the purification procedure involved gel-filtration chromatography on sephadex g-25 and g-75 columns followed by cation-exchange chromatography on a sephadex cm c-50 column. homogeneity of the purified preparation was indicated by the results of cationic polyacrylamide disc gel ... | 1981 | 16661728 |
| properties of rhizopus stolonifer polygalacturonase, an elicitor of casbene synthetase activity in castor bean (ricinus communis l.) seedlings. | some properties of the polygalacturonase-elicitor from the filtrates of rhizopus stolonifer cultures have been examined in an attempt to understand its mode of action as an elicitor of casbene synthetase activity in castor bean seedlings. both the polygalacturonase activity and the elicitor activity are heat-labile with similar heat-sensitivity profiles. also, the catalytic activity of the enzyme is lost on treatment with sodium periodate, as had been shown previously for the elicitor activity. ... | 1981 | 16661729 |
| inducibility of cytochrome p-450 and of nadph-cytochrome c reductase in progesterone treated filamentous fungi rhizopus nigricans and rhizopus arrhizus. | 1981 | 6785529 | |
| 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 ... | 1980 | 7399373 |
| 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 ... | 1979 | 485140 |
| diterpene biosynthesis in maize seedlings in response to fungal infection. | a cell-free system which catalyzes the biosynthesis of terpene hydrocarbons when supplemented with mevalonate, mn(2+), and atp was prepared from the scutellum-embryonic axis region of maize seedlings. the capacity of this system for the production of terpene hydrocarbons was enhanced 50- to 100-fold when the seedlings were exposed for 48 hours to the fungus rhizopus stolonifer prior to tissue homogenization. the fungi aspergillus niger, fusarium moniliforme, and verticillium albo-atrum also elic ... | 1979 | 16660976 |
| purification and properties of an elicitor of castor bean phytoalexin from culture filtrates of the fungus rhizopus stolonifer. | evidence has been obtained for the presence in filtrates of 3-day-old cultures of the fungus rhizopus stolonifer grown on potato-dextrose medium of both high molecular weight and low molecular weight elicitors of the production of the phytoalexin casbene in cell-free extracts of castor bean (ricinus communis l.) seedlings. the high molecular weight elicitor activity was purified by means of gel filtration chromatography. both protein and carbohydrate are associated with the most purified fractio ... | 1978 | 16660233 |
| biosynthesis of the diterpene phytoalexin casbene: partial purification and characterization of casbene synthetase from ricinis communis. | casbene synthetase from 67-hour seedlings of ricinis communis l. which had been treated with rhizopus stolonifer spores was purified 700-fold by a combination of ammonium sulfate fractionation, qae a-50 sephadex chromatography, and g-100 sephadex chromatography. polyacrylamide disc gel electrophoresis revealed that the purified fraction was heterogeneous. no casbene synthetase was detected in extracts of seedlings which had not been exposed to the fungal spores; maximum activity was obtained fro ... | 1978 | 16660566 |
| inducibility of progesterone hydroxylating enzymes in rhizopus nigricans. | 1978 | 642505 | |
| 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 ... | 1978 | 646353 |
| 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 ... | 1978 | 648975 |
| 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. | 1978 | 749414 |
| [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 ... | 1977 | 558701 |
| 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 ... | 1977 | 589785 |
| 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 |
| a possible role of cytochrome p-450 in hydroxylation of progesterone by rhizopus nigricans. | 1977 | 843352 | |
| 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 ... | 1977 | 857505 |
| 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. | 1977 | 339094 |
| 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 ... | 1976 | 1037050 |
| 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. | 1975 | 1114928 |
| 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. ... | 1975 | 1147614 |
| microbiological hydroxylation. part xvi. incubation of derivatives (mainly acetals) of 5alpha-androstane ketones with the fungi calonectria decora, aspergillus ochraceus, and rhizopus nigricans. | 1975 | 1172504 | |
| studies of the invasion of carrot root parenchyma by rhizopus stolonifer lind. | 1975 | 1186134 | |
| 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. | 1975 | 1239450 | |
| 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 |
| 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 ... | 1975 | 810877 |
| purification and properties of rna polymerases i and ii from germinated spores of rhizopus stolonifer. | 1974 | 4420468 | |
| [rhizopus nigricans ehr. action of various physical factors on the weight growth of the mycelium and on uv absorption spectra of culture filtrates]. | 1974 | 4433134 | |
| synthesis of ribonucleic acids during the germination of rhizopus stolonifer sporangiospores. | 1974 | 4435301 | |
| [effect of the number of methyl groups in the progesterone molecule on its hydroxylation by rhizopus nigricans cultures]. | 1974 | 4444567 | |
| 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. | 1974 | 4811549 |
| 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 ... | 1973 | 4728271 |
| microbiological hydroxylation of steroids. vii. the pattern of dihydroxylation of mono-oxo-5 alpha-androstanes and 5 alpha-estranes with the fungus rhizopus nigricans. | 1973 | 4739028 | |
| 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. | 1973 | 4739029 | |
| lomasome development in rhizopus stolonifer sporangiospores during anaerobiosis. | 1973 | 4752340 | |
| [effect of the incubation temperature on the growth and spore formation of penicillium italicum and rhizopus nigricans treated with ionizing radiations]. | 1973 | 4777355 | |
| fungi that infect cottonseeds before harvest. | as a part of an investigation of aflatoxins and other mycotoxins in cottonseeds at harvest, samples of seeds collected from the 1971 crop at locations across the u.s. cotton belt were examined to determine the kinds of microorganisms causing internal or seed-coat infection in the field. aspergillus flavus infection was absent from all seeds examined from most areas but was present in some samples from arizona, california, and texas. fusarium spp., alternaria sp., and a. niger caused internal inf ... | 1973 | 16349975 |
| translocation of s 35 in rhizopus stolonifer. | 1972 | 4556581 | |
| changes in soluble ribonucleic acid polymerases associated with the germination of rhizopus stolonifer spores. | 1972 | 5043713 | |
| protein synthesis during fungal-spore germination. vi. analysis of transfer ribonucleic acid from germinated and ungerminated spores of rhizopus stolonifer. | 1972 | 5070713 | |
| studies on fungal polysaccharides. ix. the acidic polysaccharide from the cell wall of rhizopus nigricans. | 1971 | 5145919 | |
| [determination of the bacterial motility rate by cultivation with rhizopus nigricans]. | 1971 | 5146296 | |
| [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]. | 1971 | 5149948 | |
| the in vitro transformation of progesterone by rhizopus nigricans ref 129. | 1971 | 5160388 | |
| [effect of some cultivation conditions on the ability of mucor fungi tieghemella hyalospora and rhizopus nigricans to effect 11 alpha-hydroxylation of steroid molecules]. | 1971 | 5567625 | |
| transformation of progesterone by aspergillus niger 100 and rhizopus nigricans ref, 129. | 1970 | 5420621 |