Uralová M, Patzeltová N, Havlík F
Research Institute of Preventive Medicine, Bratislava, Czechoslovakia.
J Hyg Epidemiol Microbiol Immunol. 1987;31(3):293-8.
The paper handles the problem of the inactivation of the toxinogenic strain Aspergillus flavus following the application of gamma radiation to wheat. The amount of the applied dose and of the absorbed dose of ionizing radiation upon the inhibition of mycelium growth and toxin production were defined. The aflatoxin B1 was determined by extracting in chloroform and developed on Silufol R within the choroform; aceton system. The applied doses of gamma radiation (3-30 kGy) have show that the absorbed dose does not inhibit aflatoxin production. By combining the action of gamma radiation with humidity of the wheat (humidity 13-15%; 25% irradiation 6 kGy) an inactivation was reached. With the help of toxicologico-genetical tests (the Dominant Lethal Mutations Test, the Three Generations Test) the influence was traced of contaminated, irradiated substrates upon the health of experimental animals. It follows from the results obtained that in long-term feeding with contaminated wheat irradiated by gamma rays no positive mutagenic activity has been recorded. It allows to presume that wheat of humidity of 25% contaminated by a weakly toxigenic strain Aspergillus flavus irradiated by a dose of 6 kGy, and wheat of a humidity of 13-15%, contaminated by a strongly toxinogenic strain of Aspergillus flavus, irradiated by a dose of 6 kGy, are no genetic risk for white rats.
本文探讨了对受黄曲霉毒素污染的小麦施加γ射线后，产毒素黄曲霉菌株失活的问题。确定了抑制菌丝生长和毒素产生时的电离辐射施加剂量和吸收剂量。黄曲霉毒素B1通过在氯仿中萃取，并在硅胶板上以氯仿；丙酮体系展开测定。施加的γ射线剂量（3 - 30千戈瑞）表明，吸收剂量并不抑制黄曲霉毒素的产生。通过将γ射线的作用与小麦湿度（湿度13 - 15%；25%湿度下照射6千戈瑞）相结合，实现了失活。借助毒理遗传学试验（显性致死突变试验、三代试验），追踪了受污染、经辐照的底物对实验动物健康的影响。从所得结果可知，长期用经γ射线辐照的受污染小麦喂养时，未记录到正向诱变活性。由此可以推测，湿度为25%、受弱产毒素黄曲霉菌株污染且经6千戈瑞剂量辐照的小麦，以及湿度为13 - 15%、受强产毒素黄曲霉菌株污染且经6千戈瑞剂量辐照的小麦，对白鼠不存在遗传风险。
