摘要
稻曲病是由稻曲菌感染所引起的水稻真菌病害。稻曲菌素是稻曲菌的次生代谢产物之一，为水溶性物质。研究发现稻曲菌素是一类环肽毒素，能够抑制真核生物微管蛋白的组装与细胞骨架的形成、抑制细胞有丝分裂，从而表现出明显的细胞毒活性，对动物和植物产生毒害作用。稻曲菌素在抗肿瘤、抗真菌和杀虫等方面具有广泛的农药和医药用途。
本论文工作对稻曲菌素的分离和纯化条件进行摸索。首先通过对采集的稻曲球进行甲醇的浸泡和蒸发浓缩而得到稻曲菌素的粗提物。然后经过石油醚、乙酸乙酯及正丁醇的萃取得到石油醚层、乙酸乙酯层和正丁醇层。经点板后分析稻曲菌素在正丁醇层含量较高。乙酸乙酯层通过切割柱后，合并为8个部分。正丁醇层经过三种大孔吸附树脂预实验后，发现大孔吸附树脂HP-20乙醇梯度洗脱法效果较好。研究结果为后续分离和纯化稻曲菌素提供了依据。
关键词：稻曲病; 稻曲病菌；稻曲菌素; 分离; 纯化
Abstract
Rice false smut is caused by the infection of the fungal pathogen Ustilaginoidea virens. Ustiloxins are water-soluble substances, which are the secondary metabolites produced by U. virens. Study found that ustiloxins are cyclopeptide mycotoxins. They are toxic to plants and animals especially for their cytotoxic activity to be antimitotic by inhibition of microtubule assembly and cell skeleton formation. Ustiloxins can be used for medicinal and agrochemical purposes acting as antitumor, antifungal and insecticidal agents.
This experiment explored the conditions of isolation and purification of ustiloxins. We obtained crude ustiloxins through the way that we socked the collected false smut balls in methanol and then evaporation the extracts. After the extraction of petroleum ether, ethyl acetate and normal butyl alcohol, we got petroleum ether level, ethyl acetate level and normal butyl alcohol level. Compared with ethyl acetate level, the quantity of ustiloxins was much higher in the normal butyl alcohol level after thin layer chromatographic analysis. Ustiloxins in the ethyl acetate level merge into eight parts after the cutting column. We made a pre-experiment about normal butyl alcohol level through three kinds of macfofeticulaf resins, and to find the method that macroporous resin HP-20 eluted by different concentrations of ethanol is better. These research results can make a basement for the next isolation and purification of ustiloxins.
Key Words：Rice false smut; Ustilaginoidea virens; ustiloxins; isolation; purification
