Toxicological Study of Fusarium moniliforme

本课题对串珠镰刀菌进行了一系列毒理学研究.各种农产品被F. moniliforme和相关物种进行了研究。进口美国玉米严重受F.念珠状。主要是镰刀菌属（Fusarium）种。moniliforme：F.仅从10个小麦样品中的一个中分离到串珠状霉菌。从中国和泰国进口的部分珍珠大麦样品被F.土壤中镰刀菌的分布研究表明，土壤中存在镰刀菌。moniliforme和F.甘蔗地土壤中仅存在亚硝化细菌.本文介绍了伏马菌素的分析方法。moniliforme的发展和建立。用这种方法测定美国玉米中的毒素浓度，发现污染严重。该方法也使我们能够研究F. moniliforme和F.串珠状变种从国内农产品和土壤中分离出的亚葡聚糖。几个菌株表现出非常高的伏马菌素B1和B2产量。本文研究了黄曲霉菌培养提取物及其柱层析分离物的毒力。本项目中分离的串珠藻通过使用各种哺乳动物培养细胞、原代培养细胞和实验动物进行检测。结果提示可能存在一种新的毒素.伏马菌素在细胞水平的毒性作用的生物化学研究表明，毒素通过抑制鞘氨醇和鞘氨醇N-乙酰转移酶活性抑制鞘脂的生物合成。

A series of toxicological studies of Fusarium moniliforme was conducted in this project.1. Contamination of various agricultural products with F. moniliforme and relating species was studied. Imported US corn was heavily contaminated with F. moniliforme. Mainly Fusarium species other than F. moniliforme were isolated from domestic barley and wheat : F. moniliforme was isolated only from one out of 10 wheat samples. A few of pearl barley samples imported from China and Thailand were contaminated with F. moniliforme.Study of distribution of Fusarium species in soil showed the presence of F. moniliforme and F. subglutinans only in soil of sugarcane farm.2. Method of analysis of fumonisin, one of the toxins produced by F. moniliforme, was developed and established. Determination of the toxin concentration in the US corn with this method revealed heavy contamination. This method also enabled us to study the toxin production by the strains of the F. moniliforme and F. moniliforme var. subgluticans isolated from domestic agricultural products and soil. Several strains showed very high producibility of fumonisin B1 and B2.3. Toxicity of cultural extracts and their column fractions of F. moniliforme isolated in this project was examined by using various mammalian cultured cells, primary cultured cees and experimental animals. The result suggested possible presence of a new toxin.4. Biochemical study of toxic effects of fumonisin at the cellular level demonstrated that the toxin inhibited the sphingolipid biosynthesis through inhibition of sphingosine and sphinganine N-acetyltransferase activity.