关键词: 瓜果腐霉, 毒素, 除草活性, 结构鉴定

Abstract:

【Objective】 In order to understand the compsition and structure of herbicidal component from Pythium aphanidermatum, the isolation and structural indentification was researched. 【Method】 The culture filtrate was extracted by ethyl acetate, petroleum, chloroform with the same volume respectively and the activity of the crude toxin was bioassayed, the toxin was separated by using the method of TLC, then the main fraction was separated by HPLC, and the structure was analyzed by the sepctrum of IR,13C-NMR and 1HNMR. 【Result】 The results showed that the ethyl acetate extracts had the strongest herbicidal activity. Using the method of TLC, the bioassay results showed that the extracts with Rf 0.19 had strongest effect on weeds and the inhibition to Digitaria sanguinalis L. and Amaranthus retroflexus L. reached five degree, the component was got using analysis, also was proved to be dimethyl o-phthalate from the sepctrum of IR, 13C-NMR and 1HNMR. 【Conclusion】 Dimethyl o-phthalate was one of the components from the toxin, and it had herbicidal activity.

Key words: Pythium aphanidermatum, toxin, herbicidal, structure identification