Publications

TitleAbstractYear
Filter
PMID
Filter
influence of solute and hydrogen ion concentration on the water relations of some xerophilic fungi.germination and growth of six xerophilic fungi, aspergillus flavus, aspergillus ochraceus, eurotium chevalieri, chrysosphorium fastidium, wallemia sebi and xeromyces bisporus were examined on media of a wide range of water activities (aw). the influence of three solutes, nacl, glycerol and a glucose/fructose mixture, was studied at ph 4-0 and ph 6-5 using a plate-slide technique. germination times and growth rates were affected by solute type, but the influence of ph was less marked. except for ...197719558
purification and properties of rennin-like enzyme from aspergillus ochraceus.an active milk-clotting enzyme was purified some 40-fold from culture supernatant of aspergillus ochraceus. the purification steps included ammonium sulfate precipitation, g-100 sephadex gel filtration, and ion exchange chromatography, using deae cellulose column. the enzyme exhibited milk-clotting activity and proteolytic behaviour, an optimum at ph 6.0 and in the range of 7--8.5, respectively. the purified enzyme was actively proteolytic against casein, haemoglobin, and bovine serum albumin at ...197831745
[proteolytic enzymes produced by aspergillus ochraceus in relation to their plasma coagulating and fibrinolytic activities].the paper describes some properties of coagulases and fibrinolytic enzymes isolated from a proteolytic complex produced by aspergillus ochraceus hp-19 during submerged cultivation on a synthetic medium. proteolytic enzymes with the plasmocoagulating activity hydrolyzed casein at the maximum rate at 45 degrees c and ph 8.0--10.0. the coagulases were stable at ph 5.0--7.0 and were rather resistant to low ph values. the enzymes were entirely inactivated at 55 degrees c within 20--30 min. the activi ...197941165
[animal experiments on the pharmacokinetics of ocrase (author's transl)].the blood level, distribution and elimination of ocrase, a protease from aspergillus ochraceus, were determined in rabbits after application of the 131i labelled enzyme in therapeutic doses.1979397495
characterization of rennin-like enzyme produced in submerged cultures of aspergillus niger. 1979400533
mycotoxicosis produced in swine by cultural products of an isolate of aspergillus ochraceus. i. clinical observations and pathology.pigs fed a ration, 25% of which was rice culture, of aspergillus ochraceus lost weight or failed to gain and became depressed. some pigs died and most developed subcutaneous edema, hydrothorax, hydroperitoneum, pulmonary atelectasis, edema of the mesentery and perirenal edema. microscopic lesions in addition to edema were primarily renal and consisted of tubular degeneration and necrosis, hyaline tubular casts, interstitial fibrosis and tubular cell regeneration. the first change found after 3 d ...1979473489
mycotoxicosis produced in swine by cultural products of an isolate of aspergillus ochraceus. ii. clinicopathologic changes.rice culture of a toxigenic strain of aspergillus ochraceus was fed at a concentration of 25% to weanling pigs for 10 days. the clinicopathological abnormalities reflected renal damage. activities of lactic dehydrogenase, glutamic-oxaloacetic transaminase and isocitrate dehydrogenase were increased in the urine but not in the serum. serum concentrations of urea nitrogen and creatinine were high. cellular and granular casts, blood, protein, and glucose were in the urine of pigs fed toxic diet. se ...1979505895
[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
[animal experimental studies on the thrombolytic effect of ocrase].the thrombolytic effect of "ocrase", a protease isolated from aspergillus ochraceus, was investigated in animal experiments. to prevent general hyperproteolysis a protease dose was used which was was neutralized by the inhibitors in the blood of the animals. experimentally produced deposition and clotting thrombi in peripheral venous or arterial vessels of mice, rats, dwarf pigs and dogs were lysed by regional and systemic administration, and the therapeutic result was estimated by vital microsc ...1977614755
antiviral agent (6-mfa) from aspergillus ochraceus--sensitivity of arboviruses in experimentally infected mice. 1978680873
mycotoxicosis produced in rats by cultural products of an isolate of aspergillus ochraceus. 1978711069
production of xanthomegnin and viomellein by species of aspergillus correlated with mycotoxicosis produced in mice.by using thin-layer chromatography and infrared spectroscopy, xanthomegnin and viomellein have been isolated and identified from species of the aspergillus ochraceus group. a correlation was established between the occurrence of these fungal quinones in the fungal cultural products and the ability of these products to induce mycotoxicosis in mice. in addition, a method was employed to estimate the amount of xanthomegnin and viomellein produced by the fungi.1978736540
production of ochratoxin a by aspergillus ochraceus nrrl-3174 before and after exposures to 60co irradiation.spores from the toxigenic organism aspergillus ochraceus nrrl-3174 were exposed to specific levels of gamma irradiation and then allowed to germinate on selected media. increases in ochratoxin a production by irradiated, compared to non-irradiated, spores were observed after inoculation of spores onto a cracked red wheat or into a synthetic liquid medium. variations in daily ochratoxin production were also observed for control and irradiated spore-derived cultures developing on both media, with ...1976938031
mycotoxicosis produced in mice by cultural products of an isolate of aspergillus ochraceus. 19761017773
[thrombolytic and pharmacodynamic properties of aspergillus ochraceus protease].the protease isolated from aspergillus ochraceus exerts a strong thrombolytic action. in in vitro experiments and in tests with animals (mice, rats, dogs) it caused lysis of fibrinous clots. the thrombolytic effect of the protease is conditioned by its direct influence on the fibrin. besides the thrombolytic action the protease, used within a definite ranges of doses, displays antithrombotic properties. the paper cites data on the acute toxicity (in mice, rats and rabbits) and on the influence o ...19751084284
[aspergillus ochraceus wilhelm toxins. iv. -- toxicity in rat by prolonged oral administration of ochratoxin a (author's transl)].adult male and female rats are given oral doses of 0.25 to 8 mg/kg of ochratoxin a daily for 10 days. this study confirms the intoxication symptomatology and weight loss observed in rat and mouse after sole administration of toxins. estimation of the dl c50 and the calculation of the detoxication coefficient show accumulation of ochratoxin a in the organism. microscopic lesions emphasize ochratoxin a aggression on hepatocytes, nephrocytes and megacaryocytes. serious renal failure may cause the a ...19751163963
microbiological hydroxylation. part xvi. incubation of derivatives (mainly acetals) of 5alpha-androstane ketones with the fungi calonectria decora, aspergillus ochraceus, and rhizopus nigricans. 19751172504
[formation of fatty acids by aspergillus ochraceus 15b growing on a hexadecane containing medium]. 19751214637
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
studies on genetic transcription. ii. induced production of new morphological traits in aspergillus ochraceus wilhelm by 2-amino-pyrimidine. 19751243839
ochratoxigenicity of aspergillus ochraceus group and penicillium verrucosum var. cyclopium strains on various media.production of ochratoxin a (oa) by strains of aspergillus ochraceus group (a. ochraceus--21, a. sclerotiorum--1, a. sulphureus--1) and penicillium verrucosum var. cyclopium strains--11, on various media was investigated. thirteen percent of a. ochraceus strains and 18% of p. verrucosum var. cyclopium formed oa growing on sterile crushed wheat for 14 days at 25 to 27 degrees c (preliminary experiments). toxin concentrations were 5.0 to 7.0 micrograms/kg. five strains oa-positive on crushed wheat ...19921343939
detoxification of polycyclic aromatic hydrocarbons by fungi.the polycyclic aromatic hydrocarbons (pahs) are a group of hazardous environmental pollutants, many of which are acutely toxic, mutagenic, or carcinogenic. a diverse group of fungi, including aspergillus ochraceus, cunninghamella elegans, phanerochaete chrysosporium, saccharomyces cerevisiae, and syncephalastrum racemosum, have the ability to oxidize pahs. the pahs anthracene, benz[a]anthracene, benzo[a]pyrene, fluoranthene, fluorene, naphthalene, phenanthrene, and pyrene, as well as several met ...19921367975
mycotoxic flora and mycotoxins in smoke-dried fish from sierra leone.examination of 20 samples of smoke-dried fish of the ethmolosa sp. commonly called "bonga", from homes and markets in njala (sierra leone) revealed the presence of 4 aspergilli species: a. flavus links ex fries, a. ochraceus wilhelm, a. tamarii kita and a. niger van tieghem. fresh or properly preserved smoke-dried fish showed no signs of fungal contamination. mouldy fish extracts contained varying amounts of aflatoxins b1, g1, g2 and ochratoxin a. isolates of a. flavus grown on yeast extract suc ...19921480216
characterization of a novel microsomal glutathione s-transferase produced by aspergillus ochraceus ts.purification and characterization of microsomal glutathione s-transferase produced by aspergillus ochraceus ts are reported. the isozymes are located in microsomes and were active against 1-chloro-2,4-dinitrobenzene, ethacrynic acid, 1,2-dichloro-4-nitrobenzene, trans-4-phenyl-3-buten-2-one,p-nitrobenzyl chloride and bromosulphophthalein. they were inhibited by n-ethylmaleimide and bromosulphophthalein. the gst isozymes produced by aspergillus ochraceus ts are indistinguishable in respect of the ...19921488053
production of an extracellular milk-clotting activity during development in myxococcus xanthus.we describe here an extracellular proteolytic activity secreted during both growth and submerged development by myxococcus xanthus dk1622. this activity yields the clotting of kappa-casein at ph 6 and is inhibited by specific inhibitors of aspartic proteases. secretion of this milk-clotting proteolytic activity (of mcp) is time regulated during the developmental cycle, with a large increase near 9 h poststarvation, but its production does not require cell-cell contact. the lack of secretion of t ...19921629171
mixed cultivation of trichoderma reesei and aspergillus ochraceus for improved cellulase production.aspergillus ochraceus imi 317911 was screened to be a high cellobiase producing strain (2.40 iu/ml). the mixed batch cultivation of trichoderma reesei qm 9414/rut c-30 and a. ochraceus imi 317911 resulted in a balanced enzyme as compared to singly grown cultures. the milled rice straw (6%, w/v) as carbon source was found suitable for production of cellulases resulting in a filter paper activity (fpa) of 1.83 iu/ml and a cellobiase production of 1.63 iu/ml after 7 days of stirred cultivation. an ...19921632200
development of gastric proteases in fetal pigs and pigs from birth to thirty six days of age. the effect of adrenocorticotropin (acth).development of the synthesis and secretion of gastric proteases was studied in 55 large white x landrace pigs from 22 days before birth (93 days gestation) to 36 days of age. the pigs came from eight litters and were 0.4 - 13.5 kg body weight. littermate pairs were treated with either saline or adrenocorticotropin (acth) from three days of age. secretion of protease activity (milk-clotting and general proteolytic activity) was investigated in anaesthetized pigs by a gastric perfusion technique u ...19911667404
[the separation of true coagulases from other enzymes of the extracellular proteolytic complex of aspergillus ochraceus by using affinity chromatography].a complex of proteases has been isolated from the cultural broth of fungi aspergillus ochraceus hp-19 by precipitation ammonium sulfate. using the method of affinity chromatography on the biospecific sorbents the conditions for separation of proteases into ones with coagulase activity and with fibrinolytic activity have been found.19911768732
mycotoxin production on different cultivars and lines of broad bean (vicia faba l.) seeds in egypt.one hundred different cultivars and lines of broad bean (vicia faba l.) seed samples were inoculated with aspergillus flavus link (cmi 102135) to determine varietal differences which may support or resist aflatoxin production. thin-layer chromatographic analysis of the chloroform extracts of the different seed samples revealed that 11 cultivars/lines were highly resistant to seed invasion and aflatoxin production while 9 cultivars/line showed partial resistance. the remaining 80 samples were sus ...19911906134
the activity of aspergillus ochraceus (fungi) on replete females of rhipicephalus sanguineus (acari: ixodidae) in natural and experimental conditions.aspergillus ochraceus wilhelm was isolated from rhipicephalus sanguineus (latreille) ticks infected under natural conditions, and developing an illness characterized by absence of oviposition, mummification and death. from the histological sections, it is deduced that a. ochraceus colonized the ticks via the anus, as posterior gut and malpighian tubules are invaded. the experimental inoculation was carried out on replete female ticks; a disease alike to that observed in naturally infected ticks ...19902093613
protective effect of fungal growth product (6mfa), assessed therapeutically against ehrlich's ascites tumor in swiss mice.6mfa is a growth product of the fungus aspergillus ochraceus (atcc 28706) obtained by fermentation in stationary culture. it has both interferon inducing and antiviral properties, in vivo and in vitro, with a relatively high margin of safety (9, 17, 18). ehrlich's ascites tumor bearing swiss albino male mice were treated with 0.5 ml of acqueous preparation of 6mfa (0.75 mg total solids) i.p. in a therapeutic regimen schedule; the sham treated mice received only pbs. 6mfa treatment produced an in ...19911897382
sixth mycelial fraction acetone (6-mfa), an interferon inducer modulates acrylamide neurotoxicity.a single i.p. administration of an immunomodulatory agent 6-mfa (a biological response modifier and antiviral agent of fungal origin, 10 mg/100g b.wt.), on 5th day of repeated acrylamide (acr, 50 mg/kg b.wt.) treatment significantly protected rats against its specific neurotoxic effects. corpus striatal 3h-spiperone binding elevated (24%) while glutathione-s-transferase (gst) activity decreased (33%) in acr group but values were markedly restored in 6-mfa alone and co-exposed group. development ...19911882702
evaluation of microbial metabolites for trypanocidal activity: significance of biochemical and biological parameters in the mouse model of trypanosomiasis.trypanosomiasis is a parasitic disease, prevailing in both humans and animals, caused by a single-cell parasite, trypanosoma spp. three microbial metabolites, namely antiamoebin, f-857 and 6-mfa, were evaluated for trypanocidal activity by using a mouse model of trypanosomiasis, which is caused by t. evansi. the significance of the biological and biochemical parameters with respect to physio-pathology of trypanosomiasis and their implications in the evaluation of new trypanocidal compounds were ...19911875553
novel metabolite structures from biotransformation of a sesquiterpenoid ketone by selected fungal strains.the sesquiterpenoid ketone, 1,4,4-trimethyltricyclo[5.4.0.0(3.5)]undec-7-en-9-one (1), was subjected to microbial transformation by six fungal strains: aspergillus niger atcc 9142, aspergillus ochraceus dsm 824, beauveria bassiana atcc 7159, cunninghamella echinulata atcc 9244, rhizopus arrhizus atcc 11.145, and absidia blakesleeana atcc 10.148. four main metabolites were formed from 1: 10(r)- and 10(s)-hydroxy-1,4,4-trimethyltricyclo-[5.4.0.0(3.5)]undec-7- en- 9-one (2 and 3, respectively), bes ...19911872996
role of siderophores in iron storage in spores of neurospora crassa and aspergillus ochraceus.spores of neurospora crassa 74a are lacking in ferritinlike iron pools, as demonstrated by mössbauer spectroscopic analysis. the cyclic hexapeptide siderophore ferricrocin constituted 47% of the total iron content in spores. after germination and growth, the ferricrocin iron pool disappeared, indicating that the metal was utilized. in spores of aspergillus ochraceus, 74% of the total iron content was bound by ferrichrome-type siderophores. siderophores may function as iron storage forms in funga ...19872960664
mycotoxin production by molds isolated from 'greek-style' black olives.seventeen mold strains were isolated from 'greek-style' black olives produced in morocco. eight of these isolates were identified as aspergillus flavus, seven as aspergillus petrakii, and two as aspergillus ochraceus wilhelm. the a. flavus strains were tested for production of aflatoxins b1, b2, g1, and g2; and a. ochraceus and a. petrakii strains were tested for production of ochratoxin, penicillic acid, patulin, and citrinin. the organisms were tested for mycotoxin production on five different ...19883079463
mould spoilage and mycotoxin formation in grains as controlled by physical means.low oxygen concentrations (less than 1%) and/or increased concentrations of co2 or n2 have been found to be highly effective in preventing the development of mould on grain and in inhibiting selected mycotoxins, e.g. aflatoxins, ochratoxin, patulin, penicillic acid and t-2. however, the levels of co2 needed to inhibit mould growth are much higher than those required for the inhibition of mycotoxin production. the degree of inhibition achieved by elevated co2 concentrations is dependent on other ...19883079472
role of the competitive microbial flora in the radiation-induced enhancement of ochratoxin production by aspergillus alutaceus var. alutaceus nrrl 3174.the radiation sensitivity and the toxigenic potential of conidiospores of the fungus aspergillus alutaceus var. alutaceus were determined after irradiation with 60co gamma rays and high-energy electrons. over the ph range of 3.6 to 8.8, the doses required for a 1 log10 reduction in viability based on the exponential portion of the survival curve ranged from 0.21 to 0.22 kgy, with extrapolation numbers (extrapolation of the exponential portion of the survival curve to zero dose) of 1.01 to 1.33, ...19911768123
seedborne fungi of sesame (sesamum indicum l) in sierra leone and their potential aflatoxin/mycotoxin production.sesame seeds (sesamum indicum l) from four different geographic locations in sierra leone were sampled for their mycoflora. three toxigenic aspergillus species: a. flavus link ex fries, a. ochraceus wilhelm, and a. tamarii kita were common to all samples. penicillium citrinum thom and two fusarium sp. were found in samples from two localities. the mycotoxins aflatoxin b1 and g1, ochratoxin a and b, and citrinin were positively identified.19883146700
l-657,398, a novel antifungal agent: fermentation, isolation, structural elucidation and biological properties.l-657,398 is a broad spectrum antifungal agent isolated from solid fermentation or from the mycelium of the liquid fermentation of aspergillus ochraceus. structurally, the compound is a novel pyrollidine related to anisomycin.19883209471
changes during lactation in the renin-like enzyme concentration in rat luteal tissue.the activity of a renin-like enzyme (rle) previously found in rat copora lutea was studied during lactation. luteal rle concentration significantly increased after delivery and reached a maximum on day 5 of lactation. plasmatic levels of prl and progesterone also increased through lactation. treatment with 2 bromo-alpha-ergocryptine, which diminished plasma prl and progesterone levels, enhanced luteal rle activity. therefore, the increase in luteal rle during lactation seems to be independent of ...19873321821
secretion of mucor rennin, a fungal aspartic protease of mucor pusillus, by recombinant yeast cells.the aspartic protease gene of a zygomycete fungus mucor pusillus was expressed in saccharomyces cerevisiae under the control of the yeast gal7 promoter. a putative preproenzyme with an nh2-terminal extension of 66 amino acids directed by the gene was processed in yeast cells and the mature enzyme, whose nh2-terminus was identical to that of the mucor enzyme, was efficiently secreted into the medium at a concentration exceeding 150 mg/l. the enzyme secreted from the recombinant yeast was more gly ...19873323844
primary structure of a precursor to the aspartic proteinase from rhizomucor miehei shows that the enzyme is synthesized as a zymogen.in order to characterize the zymogen of the milk-clotting enzyme from rhizomucor miehei, we constructed a cdna library on pbr327 in escherichia coli. aspartic proteinase-specific recombinants were isolated by colony hybridization to a specific oligonucleotide mixture, and the cdna sequence corresponding to a precursor form of the enzyme was determined. the deduced amino acid sequence shows that this secreted fungal proteinase is synthesized as a precursor. the first 22 amino acid residues in thi ...19863329734
effect of inducers on metabolism of benzo(a)pyrene in vivo and in vitro: analysis by high pressure liquid chromatography.the characterisation of metabolites formed from benzo(a)pyrene (bp) by aspergillus ochraceus ts and effect of inducers on bp metabolism are reported. the high pressure liquid chromatographic profile of bp metabolites was similar to that of mammalian microsomes furnishing diols, quinones and phenols. the production of bp-4,5-dihydrodiol (k-region diol) by aspergillus ochraceus ts seems to be novel and provides first report on bp metabolism by eukaryotic fungi. in control, phenols and quinones wer ...19883415704
variants of aspergillus alutaceus var. alutaceus (formerly aspergillus ochraceus) with altered ochratoxin a production.the present studies, using aspergillus alutaceus var. alutaceus berkeley et curtis (formerly a. ochraceus wilhelm) nrrl 3174 along with three other wild-type strains, were undertaken in an attempt to understand the effects of irradiation and other treatments on mycotoxin production in grain. bedford barley was inoculated with spores of nrrl 3174, gamma irradiated, and incubated at 28 degrees c and 25% moisture. after 10 days of incubation, two colony types, ochre (parental) and yellow (variant), ...19911768122
cloning and sequencing of a gene for mucor rennin, an aspartate protease from mucor pusillus.the aspartate protease of mucor pusillus (mucor pusillus rennin; mpr) is a milk-clotting enzyme used in the cheese industry. the partial amino acid sequence of mpr was determined and oligonucleotide probes were synthesized for cloning of the mpr gene. a clone giving positive hybridization with the probes was selected from the cosmid library. sequencing of the cloned dna revealed an open reading frame of 1281 bp without introns which encodes 361 amino acids for the expected mpr with an nh2-termin ...19863534790
microbiological diagnosis of suppurative keratitis in bangladesh.experience in setting up an inexpensive microbiology laboratory in the bangladesh national society for the blind eye hospital and training complex at chittagong is presented, together with the results of a pilot study to identify organisms responsible in 33 consecutive cases of suppurative keratitis in the chittagong area of bangladesh. of the 33 cases 21 were positively identified by means of gram stain and/or culture. two-thirds of the responsible organisms were bacteria, and one-third were fu ...19873555609
effect of roasting on ochratoxin a level in green coffee beans inoculated with aspergillus ochraceus.the heat stability of ochratoxin a in green coffee beans inoculated with aspergillus ochraceus was studied. heat treatment (roasting) at 200 degrees c for 10 or 20 min reduced the levels of ochratoxin a by only 0-12% in the dried whole beans. almost all of the ochratoxin a was infused into the coffee decoction when the roasted samples were ground and extracted with boiling water. therefore, the reduction of ochratoxin a concentration of contaminated coffee beans by roasting under these condition ...19873574430
utilization of glucose and phosphate by fungus aspergillus ochraceus during submerged fermentation and its relationship to the production of anti-viral substance 6-mfa. 19863597127
characterization of progesterone 11 alpha-hydroxylase of aspergillus ochraceus ts: a cytochrome p-450 linked monooxygenase.the monooxygenase of aspergillus ochraceus ts capable of 11 alpha-hydroxylation of progesterone has been resolved into three components and characterized as (i) cytochrome p450, (ii) nadph-cytochrome p450-reductase and (iii) phosphatidyl choline. the 11 alpha-hydroxylase was observed to be nadph dependent, and hydroxylation was enhanced by a nadph regenerating system. this fungal monooxygenase has many features in common with that of mammalian liver microsomes. the role of mammalian cytochrome p ...19873657154
use of electron beam irradiation for mold decontamination on cheddar cheese.cheddar cheese slices, surface-inoculated with either penicillium cyclopium or aspergillus ochraceus spores, were vacuum packaged and irradiated using an electron beam accelerator. following treatment at .21 and .52 kgy, the shelf-life of cheese containing p. cyclopium was extended by 3 and 5.5 d, respectively, in comparison with inoculated, untreated samples. under similar treatment and storage conditions, cheese containing a. ochraceus exhibited average shelf-life extensions of 42.5 and 52.2 d ...19921541727
anti-inflammatory activity of 6mfa, a compound obtained from fungus aspergillus ochraceus.6mfa, an interferon-inducing substance obtained from fungus, aspergillus ochraceus, has shown anti-inflammatory activity both in acute and chronic animal models of inflammation. it was found that 6mfa was equally effective in inhibiting both exudative as well as granulative phase of inflammation. the compound suppressed also cellular migration during inflammatory process and potentiated significantly the anti-inflammatory activity of indomethacin. the compound was devoid of analgesic or antipyre ...19863784110
production of ochratoxins by some egyptian aspergillus strains.in all the investigated aspergillus ochraceus and a. alliaceus strains the maximum quantities of ochratoxins produced on yeast extract-sucrose (yes) medium exceeded that detected on wheat solid medium except a. ochraceus 67. the shake cultures lowered ochratoxins formation. the maximum yields of ochratoxins did not coincide with maximum fungal growth. in most a. strains investigated, the total ochratoxin contents of the culture filtrates highly exceeded that of the mycelia.19921509830
isolation and structure determination of natural analogues of the mycotoxin ochratoxin a produced by aspergillus ochraceus.three new natural mycotoxins, analogues of ochratoxin a, in which the phenylalanine moiety is replaced by serine, hydroxyproline or lysine, were isolated from cultures of aspergillus ochraceus by tlc followed by hplc column chromatography. their structures were determined after acidic hydrolysis by the characterisation of both their amino acid moieties and of ochratoxin alpha, the chlorinated dihydroisocoumarin moiety of ochratoxin a. these structures were confirmed by mass spectrum analysis.19921471160
[inhibition of eight natural foods on mutagenic effect by aflatoxin b1 and extracts of fungi].eight natural foods were tested for their antimutagenic activities on afb1, metabolic extracts of a. versicolor and a. ochraceus which induced mutagenic activity in ta 98 and ta 100 mutants. the tested substances were extracted repeatedly with acetone. the revertance induced by afb1, metabolic extracts of a. versicolor and a. ochraceus were significantly decreased when the eight natural foods were added into the medium. the results showed that the eight natural foods had different degrees of ant ...19921451583
new diketopiperazine metabolites from the sclerotia of aspergillus ochraceus.three new diketopiperazine-containing metabolites 1-3 have been isolated from the sclerotia of aspergillus ochraceus (nrrl 3519) by chromatography on sephadex lh-20 and reversed-phase hplc. the structures of these compounds were established using extensive high-field 1d and 2d nmr experiments. all three compounds cause moderate reduction in weight gain in assays against the lepidopteran crop pest helicoverpa zea.19921402958
[isolation of a fibrinolytically active protease from aspergillus ochraceus]. 19714106006
[effect of a protease from aspergillus ochraceus on platelet function]. 19714106008
[microbiological isolation of a protease with fibrinolytic effect from aspergillus ochraceus]. 19744134259
[animal experimental studies on a protease from aspergillus ochraceus]. 19744134260
[clinical and coagulation physiological studies on a protease from aspergillus ochraceus (preliminary report)]. 19744134261
[characterization of an alkaline protease form aspergillus ochraceus]. 19744134483
studies on the proteolysis of fibrinogen and fibrin by aspergillus ochraceus enzyme as compared to the action of plasmin. 19744134484
medium-scale production and purification of ochratoxin a, a metabolite of aspergillus ochraceus.the preparation of crystalline ochratoxin a from aspergillus ochraceus nutrient solution is described. methods are adaptable to large-scale fermentations.19724336018
fibrinolysis by protease of aspergillus ochraceus. 19724669810
influence of nitrogen source on the synthesis of fat from sucrose by aspergillus terreus, aspergillus ochraceus, cladosporium fulvum, cladosporium herbarum and penicillium gladioli. 19724672593
[aspergillus ochraceus protease: an additional enzyme for the determination of incomplete erythrocyte antibodies]. 19724675273
microbiological hydroxylation of steroids. vi. hydroxylation of simple mono- and di-oxygenated 5 -androstanes and of 3-oxoestranes with the fungus aspergillus ochraceus. 19724675916
effect of zinc, copper, and iron on ochratoxin a production.the effect of zinc, copper, and iron levels on production of ochratoxin a by aspergillus ochraceus wilhelm in a synthetic medium in a shake culture was investigated. optimal concentrations of znso(4), cuso(4), and fecl(3) for ochratoxin a production were 0.055 to 2.2 mg/liter, 0.004 to 0.04 mg/liter, and 1.2 to 24 mg/liter, respectively. zinc and copper levels greater than optimum reduced the rate of ochratoxin accumulation without altering either glutamate or sucrose utilization. ochratoxin a p ...19734715563
production of ochratoxins a and b on country cured ham.two strains of aspergillus ochraceus and six of penicillium viridicatum isolated from country cured hams were screened for production of ochratoxins a and b. none of the isolated p. viridicatum strains yielded detectable amounts of ochratoxin a or b, whereas both strains of a. ochraceus produced ochratoxins a and b on rice, defatted peanut meal, and country cured ham. after 21 days of incubation on ham, one-third of the toxin was found in the mycelial mat on the ham surface, whereas two-thirds h ...19734737852
effect of time and temperature on ochratoxin a production by aspergillus ochraceus. 19734762800
the component fatty acids of aspergillus ochraceus fat. 19734764005
comparative toxicity of ochratoxin a and crude aspergillus ochraceus culture extract in japanese quail (coturnix coturnix japonica). 19734789009
production of penicillic acid and ochratoxin a on poultry feed by aspergillus ochraceus: temperature and moisture requirements.a strain of aspergillus ochraceus wilhelm, isolated from poultry feed, produced both penicillic acid and ochratoxin a. studies demonstrating the ability of this fungus to colonize poultry feed and produce these two mycotoxins under various temperatures and moistures indicated that the interaction was complex. the optimal temperature for conidial development did not vary with moisture, but accumulation of both toxins did. a combination of low temperature, 15 or 22 c, and low moisture favored the ...19734795527
efects of dichlorvos on ochratoxin production by aspergillus ochraceus. 19744840523
rapid method for preparing cell-free extracts of aspergillus ochraceus.a rapid method for preparing cell-free extracts of aspergillus ochraceus was developed. mycelial mats were prefrozen in liquid nitrogen, ground to a fine powder in a cold mortar, and homogenized in an all-glass mechanical homogenizer. this method provided preparations averaging 43.0 mg of protein per g of mycelium (wet weight). the method was fast, efficient, and did not subject the extract to temperatures above 1 c or to heavy metals. the preparation method was suitable for studying a varie ...19751115500
[metabolism of anthranilic acid and para-aminobenzoic acid in aspergillus ochraceus]. 19664961213
bioproduction of ochratoxin a and penicillic acid by members of the aspergillus ochraceus group. 19725032809
analysis of tobacco and smoke condensate for penicillic acid.gas chromatographic analyses of smoke condensate from commercial, unfiltered cigarettes spiked with penicillic acid (500 or 1,000 ppm), a reported carcinogenic substance from certain fungi, indicated approximately 3% of unchanged compound was transported in the smoke. analysis of tobacco on which either aspergillus ochraceus or penicillium cyclopium was grown revealed microgram quantities of the compound. small amounts of the material were also found in moldy tobacco from commercial storage. the ...19725057371
mellein and 4-hydroxymellein production by aspergillus ochraceus wilhelm.mellein and 4-hydroxymellein are isocoumarin compounds produced by aspergillus ochraceus wilhelm. they are structurally similar to the dihydroisocoumarin moiety of ochratoxin a, a toxic metabolite of the same fungus, and they possibly have similar biological properties. production of mellein and 4-hydroxymellein on synthetic media and natural solid substrates was determined. several carbon and nitrogen sources supported production of these metabolites in stationary culture. additional zinc and m ...19725064985
[fibrinolytic activity of a protease isolated from aspergillus ochraceus]. 19715103710
incorporation of chlorine-36 into ochratoxin a.incubation of aspergillus ochraceus nrrl 3174 in a medium containing na(36)cl incorporated (36)cl into ochratoxin a. the highest incorporation (0.75 and 0.70%, respectively) was obtained when the radioactive chloride was added to the medium by the 2nd or 3rd day of incubation.19715119199
[isolation and properties of a fibrinolytically active protease from aspergillus ochraceus]. 19715153302
an improved 11 alpha-hydroxylation of progesterone by aspergillus ochraceus ts.1. the stereospecific hydroxylation of progesterone exclusively to its 11 alpha-hydroxy derivative by aspergillus ochraceus ts is reported. 2. there is no secondary metabolite (6beta, 11 alpha-dihydroxyprogesterone) formed even when the transformation was attempted with different concentrations of the substrate (200 microgram/ml-200 mg/ml) for prolonged with zn2+ at a concentration of 50 microgram/ml identical results were obtained. 3. similar results were also obtained at different ph values of ...1978743260
microbial hydroxylations. v. 11-alpha-hydroxylation of progesterone by cell-free preparations of aspergillus ochraceus. 19705417182
mycotoxicity of aspergillus ochraceus to chicks.five isolates of aspergillus ochraceus, obtained from peanuts, were grown separately on sterile, moist corn for 14 days and fed to 1-day-old babcock b-300 cockerels to evaluate their toxic effects. two isolates were highly toxic, causing death of all birds during the 1st week of the experiment. two isolates were moderately toxic, causing severe growth suppression with some deaths occurring throughout the 3-week test period. one isolate had no apparent effect. when the two most toxic isolates (di ...19705418941
ochratoxin a: inhibition of mitochondrial respiration.ochratoxin a is a fungal metabolite which induces pathological changes in animals. the toxin was isolated from cultures of aspergillus ochraceus and purified by thin-layer chromatography. ochratoxin a and one of its hydrolysis products, dihydroisocoumarin, severely inhibited coupled respiration when applied at low concentration to rat liver mitochondria.19705441684
studies in mycological chemistry. xxiv. synthesis of ochratoxin a, a metabolite of aspergillus ochraceus wilh. 19705460860
production of ochratoxin a by aspergillus ochraceus isolated in japan from moldy rice.a simple thin-layer chromatography-fluorodensitometric method for quantitative analysis of ochratoxin a was developed. this method proved to be of use in investigating the production of the toxin and the nutritional factors affecting the toxin production by two strains of aspergillus ochraceus isolated from moldy rice in japan. these fungi produced large amounts of ochratoxin a in a nutrient solution containing 1% l-phenylalanine and 2% yeast extract.19705485726
chemical and cytotoxicity survey on the production of ochratoxins and penicillic acid by aspergillus ochraceus wilhelm. 19705494852
the isolation of secalonic acid a from aspergillus ochraceus cultured on rice. 19715544365
production of ochratoxins in different cereal products by aspergillus ochraceus.the effects of temperature and length of incubation on ochratoxin a production in various substrates were studied. the optimal temperature for toxin production by aspergillus ochraceus nrrl-3174 was found to be around 28 c. very low levels of ochratoxin a are produced in corn, rice, and wheat bran at 4 c. the optimal time for ochratoxin a production depends on the substrate, ranging from 7 to 14 days at 28 c. ochratoxin b and dihydroisocoumaric acid, i.e., one of the hydrolysis products of ochra ...19715564676
large-scale transformation of steroids by fungal spores.spores of aspergillus ochraceus and septomyxa affinis were produced on a large scale by surface sporulation on moist wheat bran and barley. 11alpha-hydroxylation of progesterone and reichstein's compound s by spores of a. ochraceus and 1-dehydrogenation of compound s by spores of s. affinis were carried out in 5-liter fermentors. it was shown that, above a certain minimum, increase in aeration and agitation did not significantly affect steroid conversion. the industrial feasibility of the spore ...19685645421
microbial hydroxylations. ii. oxidative cleavage of the 17-beta-acetyl side-chain of progesterone by aspergillus ochraceus. 19685660090
11 alpha-hydroxylation of steroids by spores of aspergillus ochraceus. 19685661060
11 alpha-hydroxylation of steroids by spores of aspergillus ochraceus. 19685665975
production of xanthomegnin and viomellein by isolates of aspergillus ochraceus, penicillium cyclopium, and penicillium viridicatum.fungal isolates from legumes were cultured on rice and examined for production of the toxic mold metabolites xanthomegnin and viomellein. six of 14 aspergillus ochraceus isolates produced from 0.3 to 1.3 mg of xanthomegnin per g and 0.1 to 1.0 mg of viomellein per g. one of nine isolates of penicillium cyclopium produced 0.1 mg of xanthomegnin per g and 0.06 mg of viomellein per g. three of nine p. viridicatum isolates produced from 0.4 to 1.6 mg of xanthomegnin per g and 0.2 to 0.4 mg of viomel ...1978708029
studies on growth inhibition by lectins of penicillia and aspergilli.it has previously been shown in our laboratory that wheat germ agglutinin (wga) binds to trichoderma viride and inhibits growth of this fungus. here we report on the effect of wga, soybean agglutinin (sba) and peanut agglutinin (pna) on penicillia and aspergilli. binding of the lectins to the fungi was examined with the aid of their fluorescein isothiocyanate (fitc) conjugated derivatives. fitc-wga bound to young hyphal walls of all species, in particular to the hyphal tips and septa, in agreeme ...1978637658
ochratoxin a, a toxic metabolite produced by aspergillus ochraceus wilh. 19655833211
mycotoxins. ii. the constitution of ochratoxins a, b, and c, metabolites of aspergillus ochraceus wilh. 19655892024
Displaying items 1 - 100 of 512