牛筋草内生菌砖红链霉菌CSF09杀虫成分鉴定及活性初步研究

Identification and investigation on the insecticidal activity of Streptomyces lateritius CSF09, an endophyte strain from Eleusine indica(L.) Gaertn

为了从微生物中筛选天然杀虫活性化合物,从牛筋草中分离到1株具有杀虫活性的内生放线菌砖红链霉菌Streptomyces lateritius CSF09。采用大孔吸附树脂提取和硅胶柱层析技术,从CSF09菌株发酵液中分离到1个杀虫活性成分,通过质谱和核磁共振波谱鉴定了其化学结构,并初步测定了该化合物对3龄粘虫幼虫和家蝇成虫的杀虫活性。结果表明:该菌株发酵液中的杀虫活性成分为4-甲氧基水杨醛,发酵单位约为13 mg/L;4-甲氧基水杨醛对家蝇和粘虫均表现出一定的触杀活性,其中对家蝇的LD_(50)值为1.51μg/头,对粘虫毒力较弱,以10μg/头剂量处理时校正死亡率仅为36.6%;4-甲氧基水杨醛杀虫活性的突出特性是作用迅速,其击倒中时(KT50)大多在5 min以内。研究表明,4-甲氧基水杨醛具有一定的卫生杀虫剂开发应用潜力。

To discover insecticidal ingredients from natural products, Streptomyces lateritius CSF09, an endophyte strain was isolated from Eleusine indica （L.） Gaertn. The bioactive compound was isolated from the fermentation broth by techniques of macroporous resin extraction and silica gel column chromatography, and its chemical structure was identified by MS and NMR. The obtained compound was subjected to evaluate its insecticidal activity against the 3rd larvae of Mythimna separate and adults ofMusca domestica. The results indicated that the insecticidal ingredient produced by the strain was 4- methoxysalicylaldehyde with the yield of approximately 13 mg/L. 4-Methoxysalicylaldehyde showed contact toxicity against both M. separate and M. domestica. The LDs0 value ofM. domestica was 1.51 μg/fly. 4-Methoxysalicylaldehyde showed weak toxicity against M. separate, and the mortality rate was only 36.6% after the treatment of 10 μg/larvae. The outstanding characteristic of the insecticidal activity of 4-methoxysalicylaldehyde was quick-acting with the KT50 in most treatments less than 5 min. This investigation suggested that 4-methoxysalicylaldehyde has the potential to be developed as a health insecticide.