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Production of trichothecene and non-trichothecene mycotoxins by Fusarium species isolated from maize in Minnesota 总被引:1,自引:0,他引:1
Eighty-two cultures of Fusarium species isolated in 1986 from moldy maize in Minnesota were each cultured on rice for 4 weeks and found to produce the following mycotoxins: F. graminearum isolates, deoxynivalenol (DON, 4–225 g/g), 3-acetyldeoxynivalenol (3-ADON, 2–4g/g), 15-acetyldeoxynivalenol (15-ADON, 1–35 g/g) and zearalenone (ZEA, 5–4350 g/g); F. moniliforme, fusarin C (detectable amounts to 1000 g/g); F. mòniliforme, F. oxysporum, F. proliferatum and F. subglutinans isolates, moniliformin (15–6775 g/g); F. moniliforme, F. proliferatum, and F. subglutinans isolates, fusaric acid (detectable amounts). Other mycotoxins screened for in each rice sample and not detected were T-2 toxin, HT-2 toxin, neosolaniol, T-2 tetraol, nivalenol, fusarenon-X, scirpenols, alpha and beta trans-zearalenols, wortmannin, and fusarochromanone. The rat feeding bioassay indicated that other, unidentified toxins may be present. 相似文献
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A minority of 46,XX true hermaphrodites are positive for the Y-DNA sequence including SRY 总被引:4,自引:0,他引:4
Ken McElreavey Raphaël Rappaport Eric Vilain Nacer Abbas François Richaud Stéphen Lortat-Jacob Roland Berger Maryvonne LeConiat Chafika Boucekkine Kiran Kucheria Samia Temtamy Claire Nihoul-Fekete Raja Brauner Marc Fellous 《Human genetics》1992,90(1-2):121-125
Summary A total of 30 cases of 46,XX true hermaphroditism was analysed for Y-DNA sequences including the recently cloned gene for male testis-determination SRY. In 3 cases, a portion of the Y chromosome including SRY was present and, in 2 cases, was localised, to Xp22 by in situ hybridisation. Since previous studies have shown that the majority of XX males are generated by an X-Y chromosomal interchange, the Xp22 position of the Yp material suggests that certain cases of hermaphroditism can arise by the same meiotic event. The phenotype in the 3 SRY-positive cases may be caused by X-inactivation resulting in somatic mosaicism of testis-determining factor expression giving rise to both testicular and ovarian tissues. Autosomal or X-linked mutation(s) elsewhere in the sex-determining pathway may explain the phenotype observed in the remaining 27 SRY-negative cases. 相似文献
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Samples of wheat naturally infected by Fusarium graminearum Schwabe were obtained from mills in Oklahoma, Missouri, Kansas, and Minnesota and fields in Nebraska and Kansas in 1982; they were analyzed for deoxynivalenol (DON). The wheat was milled, and DON was found throughout all the milling fractions (bran, shorts, reduction flour, and break flour). The DON recoveries for each mill run ranged from 90 to 98%. These samples, regardless of DON concentration, also gave similar fractional distributions of DON. The greatest (21 ppm [21 micrograms/g]) concentration of DON was found in the bran, and the smallest (1 ppm) was found in the break flour. Cleaning and milling were not effective in removing DON; DON was not destroyed in the bread baked from the naturally contaminated whole wheat flour, but the effect on its concentration in the samples analyzed varied, the reduction ranging from 19 to 69%. The percent reduction found in the cleaned wheat ranged from 6 to 19%. DON concentrations in the following commercially made breads, caraway rye, seedless rye, and pumpernickel, were 45 ppb (ng/g), 39 ppb, and 0 ppb, respectively. The limits of detection by gas chromatography-mass spectrometry and high-pressure liquid chromatography for DON were 0.5 and 10 ng, respectively. 相似文献
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Benzyl 2-acetamido-2-deoxy-3-O-methyl-α-d-glucopyranoside (3) was obtained by deacetalation of its 4,6-O-benzylidene derivative (2). Compound 2 was prepared by methylation of benzyl 2-acetamido-4,6-O-benzylidene-2-deoxy-α-d-glucopyranoside with methyl iodide-silver oxide in N,N-dimethylformamide. Diol 3 was selectively benzoylated and p-toluenesulfonylated, to give the 6-benzoic and 6-p-toluenesulfonic esters (4 and 5, respectively). Displacement of the sulfonyl group of 5 with sodium benzoxide in benzyl alcohol afforded the 6-O-benzyl derivative (6). Glycosylation of 4 with 2,3,4,6-tetra-O-acetyl-α-d-galactopyranosyl bromide (7) in dichloromethane, in the presence of 1,1,3,3-tetramethylurea, furnished the disaccharide derivative 8. Similar glycosylation of compound 6 with bromide 7 gave the disaccharide derivative 10. O-Deacetylation of 8 and 10 afforded disaccharides 9 and 11. The structure of compound 9 was established by 13C-n.m.r. spectroscopy. Hydrogenolysis of the benzyl groups of 11 furnished the disaccharide 2-acetamido-2-deoxy-4-O-β-d-galactopyranosyl-3-O-methyl-d-glucopyranose (N-acetyl-3-O-methyllactosamine). 相似文献
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Thirty-four isolates of Fusarium moniliforme were obtained from cereal grains collected in various parts of the world. The isolates were grown on rice and tested as a diet for toxicity to rats. Of these isolates, 53% caused death, 12% caused congestion and hemorrhage of the stomach and intestine as well as hematuria, 21% caused diarrhea, 38% caused weight loss, and 9% were nontoxic. The cultures were tested to T-2, HT-2, neosolaniol, acetyl-T-2, T-2-tetraol, iso-T-2, diacetoxyscirpenol, monoacetoxyscirpenol, deoxynivalenol, nivalenol, fusarenone-X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, zearalenone, moniliformin, fusarochromanone, fusarin-C, and wortmannin; all were negative. In addition, F. moniliforme NRRL A25820 was grown on corn and banana fruit as solid substrates as well as on a defined liquid medium; none of the above toxins were found. When F. moniliforme NRRL A25820 was incorporated into a rat diet, no toxicity was noted. Twenty-eight additional isolates of F. moniliforme, isolated from feed associated with equine leukoencephalomalacia, were grown on cracked corn for 2 weeks. The cultures were negative when tested for deoxynivalenol, 15-acetyldeoxynivalenol, diacetoxyscirpenol, monoacetoxyscirpenol, nivalenol, and fusarenone X. Seventy-five percent of the isolates were toxic to ducklings, indicating the presence of a toxin other than trichothecenes. Our results support the conclusion that F. moniliforme does not produce trichothecenes. 相似文献
10.
The prevalence and distribution of soil-inhabitingFusarium species in the soil of vegetable crops grown under custom-made plastic tunnels were studied at three geographical locations on the island of Bahrain. Six species ofFusarium representing a total of 1154 isolates were isolated on modified Komada medium. All species reported in this survey are recorded for the first time from the hot, arid desert of Bahrain.Fusarium solani andF. oxysporum were among the most frequently isolated fungi in all locations and crops. 相似文献