INTERCONVERSION OF AFLATOXIN-B1 AND AFLATOXICOL BY SEVERAL FUNGI
INTERCONVERSION OF AFLATOXIN-B1 AND AFLATOXICOL BY SEVERAL FUNGI
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DOI：
10.1128/aem.56.5.1465-1470.1990
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发表时间：
1990-05-01
影响因子：
4.4
通讯作者：
KASAI, N
中科院分区：
文献类型：
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作者：
NAKAZATO, M;MOROZUMI, S;KASAI, N
4株真菌，即尼日尔曲霉、草本散囊菌、根霉、不产黄曲霉毒素（AF）的黄曲霉可将AF-B1转化为黄曲霉毒素（AFL），也可将AFL再转化为AF-B1。AF-B1与AFL、AFL与AF-B1的相互转化发生在真菌的增殖过程中。这些反应在从A. flavus和Rhizopus sp.，但在来自相同菌株的完整（未破碎）菌丝体的培养物中未观察到它们。当无细胞体系在100 ℃预热时，没有观察到AF-B1和AFL的相互转化活性。C.这些结果表明，AF-B1和AFL的相互转化是由A.此外，在培养基中观察到的AFL-A到AFL-B的异构化也被发现通过降低培养pH而发生。
Four fungal strains, namely, Aspergillus niger, Eurotium herbariorum, a Rhizopus sp., and non-aflatoxin (AF)-producing Aspergillus flavus, which could convert AF-B1 to aflatoxicol (AFL), could also reconvert AFL to AF-B1. The interconversion of AF-B1 to AFL and of AFL to AF-B1 was ascertained to occur during proliferation of the fungi. These reactions were distinctly observed in cell-free systems obtained from disrupted mycelia of A. flavus and the Rhizopus sp., but they were not observed in culture filtrates from intact (nondisrupted) mycelia of the same strains. The interconversion activities of AF-B1 and AFL were not observed when the cell-free systems were preheated at 100.degree. C. These findings strongly suggest that the interconversion of AF-B1 and AFL is mediated by intracellular enzymes of A. flavus and the Rhizopus sp. In addition, the isomerization of AFL-A to AFL-B observed in culture medium was also found to occur by the lowering of the culture pH.