Adebajo L O, Idowu A A, Adesanya O O
Department of Biological Sciences, Ogun State University, Ago-Iwoye, Nigeria.
Mycopathologia. 1994 Jun;126(3):183-92. doi: 10.1007/BF01103774.
Thirty-one fungal species, mostly toxigenic and belonging to 11 genera were isolated from corn, corn cake and corn roll snack samples. Aspergillus, Penicillium and Fusarium accounted for 10, 6 and 3 of the species and altogether, they constituted 90, 94 and 88 percent of the total fungi in corn, corn cake and corn roll snack respectively. Mycotoxins (aflatoxins and ochratoxin A) were detected in 45, 80 and 12 percent while the means and ranges of the total aflatoxins recorded were: 200(25-770 ppb); 233(15-1070 ppb) and 55(10-160 ppb) for corn, corn cake and corn roll snack samples respectively. Ochratoxin A was detected at toxicologically significant levels in only 15 percent of the corn cake samples analyzed. All the strains of Aspergillus flavus and A. ochraceus tested produced aflatoxin B and ochratoxin A, respectively, when they were cultured on each of the three substrates. In each case, substantial quantities of the toxins were produced from 25 to 35 degrees C with the peak level recorded at 30 degrees C. Toxin production was detected only in substrates with 15 percent moisture content and above; reaching the maximum at 25 or 30 percent moisture level. No substantial differences in the amount of toxins were elaborated with further increase in substrates' moisture content. Of the three substrates, corn cake was the most suitable for aflatoxin B production while they were all equally suitable for the elaboration of ochratoxin A.
从玉米、玉米饼和玉米卷零食样品中分离出31种真菌，大多具有产毒能力，分属于11个属。曲霉属、青霉属和镰刀菌属分别有10种、6种和3种，它们在玉米、玉米饼和玉米卷零食中的真菌总数中分别占90%、94%和88%。在45%、80%和12%的样品中检测到了霉菌毒素（黄曲霉毒素和赭曲霉毒素A），记录的总黄曲霉毒素的平均值和范围分别为：玉米样品200（25 - 770 ppb）；玉米饼样品233（15 - 1070 ppb）；玉米卷零食样品55（10 - 160 ppb）。在分析的玉米饼样品中，仅15%检测到具有毒理学显著水平的赭曲霉毒素A。所有测试的黄曲霉和赭曲霉菌株在三种底物上培养时，分别产生了黄曲霉毒素B和赭曲霉毒素A。在每种情况下，25至35摄氏度时产生大量毒素，30摄氏度时达到峰值水平。仅在水分含量为15%及以上的底物中检测到毒素产生；在25%或30%的水分水平时达到最大值。随着底物水分含量进一步增加，毒素量没有显著差异。在这三种底物中，玉米饼最适合黄曲霉毒素B的产生，而它们都同样适合赭曲霉毒素A的产生。
