Abstract An enzymatic assay system has been developed to measure the relative potency of fungicides such as triadimefon, triarimol, triforine, and buthiobate as inhibitors of sterol 14-demethylation. The enzyme preparation used is the 8000 g supernatant derived from a homogenate of an aerobically adapted, anaerobically grown, high sterol strain of Saccharomyces cerevisiae . After incubation of the enzyme with [2- 14 C]mevalonic acid and the fungicide the ratio, radioactivity in 4,4-dimethyl sterols/radioactivity in 4-demethyl sterols is determined. The higher this ratio is, the more efficient is the fungicide as an inhibitor of fungal sterol 14-demethylation. The ratio has been determined for a number of commercial fungicides and two series of triazole compounds. A similar assay system based on the 10,000 g supernatant from a rat liver homogenate was also tested but gave an inaccurate assessment of the relative potency of fungicides as inhibitors of fungal sterol 14-demethylation.

中文翻译：

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一些杀菌剂作为甾醇 14-去甲基化抑制剂的效力比较

摘要 已开发出一种酶促测定系统来测量杀真菌剂（如三唑酮、三苯甲醚、三甲双胍和丁硫磷）作为甾醇 14-去甲基化抑制剂的相对效力。所用的酶制剂是 8000 g 上清液，该上清液来自一种经过有氧适应、厌氧生长的酿酒酵母高甾醇菌株的匀浆。在酶与[2- 14 C]甲羟戊酸和杀真菌剂温育之后，测定4,4-二甲基甾醇中的放射性/4-去甲基甾醇中的放射性的比率。该比率越高，杀真菌剂作为真菌甾醇14-去甲基化抑制剂的效率越高。已经确定了许多商业杀菌剂和两个系列的三唑化合物的比例。基于 10 的类似分析系统，