燕麦镰刀菌GD-2产除草活性物质的初步研究
Primary Study of Herbicidal Active Metabolitesfrom Fusarium avenaceum GD-2

为明确燕麦镰刀菌(Fusarium avenaceum)中除草活性物质，以野燕麦种子为靶标，采用活性追踪法，对燕麦镰刀菌正丁醇萃取物进行活性成分分离和活性测定。正丁醇萃取液旋转蒸发去溶剂后进行硅胶柱层析，以二氯甲烷和甲醇的混合液进行梯度洗脱，每50 mL收集为一个馏分，共收集到50个馏分。生物测定结果表明：以二氯甲烷和甲醇的体积比为20∶1的混合液，洗脱得到的馏分24～27对供试杂草野燕麦表现出较强的活性，其对野燕麦的除草抑制作用均为4级。合并馏分24～27，以二氯甲烷和甲醇的体积比为15∶1的混合液作为展开剂进行薄层层析(TLC)，通过生物测定结果表明，Rf值在0.47～0.58的活性条带对野燕麦有较强的除草抑制活性，对野燕麦的除草抑制作用达到5级。HPLC分析发现，该活性条带主要含有3个组分，最大吸收峰在260 nm，其保留时间分别为6.378、19.721和22.403 min。
In order to study herbicidal substances of Fusarium avenaceum against wild oat, Avenafatua L.seeds was used to screen herbicidal components from n-butanol extracts by bioassay. The n-butanol extracts were separated gradually by silica gel column using dichloromethane and methanol mixtures (V∶V=20∶1) as the developers. Eluents were collected in each 50 mL and 50 fractions were used for bioassay. The results revealed that fraction 24-27 showed strong activity against Avenafatua L. with the inhibition level of 4.The combined fractions of 24-27 were eluted with the mixture of dichloromethane and methanol (V∶V=15∶1) as the developer and active bands were collected. Bioassay results showed that the bands with Rf0.47-0.58 had the stronger inhibitory activity against Avenafatua L. and the inhibition to weed reached four degree. HPLC analysis suggested that this fraction mainly contained 3 components and had the maximum absorption peak at 260 nm,the retention time of which was 6.378, 19.721 and 22.403 min respectively.