油菜内生枯草芽孢杆菌BY-2抗油菜菌核病菌有效成分的鉴定和分离提纯

油菜内生枯草芽孢杆菌(Bacillus subtilis)BY-2产生2种类型的抗真菌物质，一种是挥发性的de物质，可以有效地抑制油菜菌核病菌的生长；另一种是分泌到培养液中的物质。重点研究第二类抗菌物质的提取和纯化分析方法。试验证明BY-2 产生和积累高效抑制油菜菌核病菌（Sclerotinia sclerotiorum (Lib.)de Bary）生长的细胞外分泌型物质，其发酵上清液与油菜菌核病菌对峙培养形成了2.8 cm的抑菌圈；采用离心收集发酵液上清液、调节酸性条件、甲醇溶解和Sephadex G25葡聚糖凝胶柱层析等方法，可以沉淀、萃取收集和纯化该物质，而且收集率高、活性强、纯度高。

Identification and purification of anti-Sclerotinia sclerotiorum substance from endobacterium BY-2 in oilseed rape

The endophytic Bacillus subtilis BY-2 isolated from oilseed rape produces two kinds of antifungal substance,one is a volatile component that could effectively inhibit the growth of Sclerotinia sclerotiorum and the other is secreted into the culture medium.The extraction and purification of extracellular secreted substance was studied.Results showed that BY-2 produced largely extracellular secreted substance and controlled effectively plant disease caused by S.sclerotiorum.The inhibition zone reached to 2.8 cm in confronting incubation test of BY-2 and S.sclerotiorum.This substance could be collected and purified by collecting supernatant,adjusting pH,methanol extraction and gel filtration methols.