产杀虫抗菌单端孢霉烯族毒素海绵真菌Myrothecium verrucaria Hmp-F73的筛选和鉴定

Isolation and Identification of a Marine Fungus Myrothecium verrucaria Hmp-F73 Producing Trichothecene with Insecticidal and Antimicrobial Activities

从98株分离自大连海域繁茂膜海绵Hymeniacidon perleve共附生的真菌中,筛选得到具有较强杀虫抗菌活性的丝状真菌Hmp-F73。96孔板卤虫生物检测(brine shrimp assay,BSA)结果显示,该菌株发酵滤液甲醇提取物浓度为0.25μg.mL-1时,卤虫校正死亡率为100%;甲醇提取物经硅胶柱层析洗脱得到7个馏分,其中馏分3浓度为400μg.mL-1时对甜菜夜蛾具明显抑制取食活性,拒食率达到85.25%;1mg.mL-1的馏分6对玉米纹枯病菌Rhizoctonia solani抑菌圈直径达9.25mm。经色谱柱层析分离纯化得到4个杀虫抗菌活性化合物,氢核磁数据显示这些化合物均属于12,13-环氧单端孢霉烯族化合物。通过形态、培养特征及ITS1-5.8S-ITS2序列分析,将该菌株鉴定为疣孢漆斑菌Myrothecium verrucaria。

Total 98 fungal strains isolated from the marine sponge Hymeniacidon perleve collected in Dalian,Liaoning,were screening for insecticidal and antimicrobial activities.A marine mycelial fungus strain Hmp-F73 was obtained based on brine shrimp assay.When the concentration of the methanolic extract from fermentation broth was 0.25 μg·mL-1,the corrected mortality of brine shrimp was 100%.The methanolic extract was portioned with silica gel column chromatography,and 7 fractions were obtained.Fraction 3 at the concentration of 400 μg·mL-1 could inhibit the feeding of Spodoptera exigu by the antifeedant rate of 85.25%.Fraction 6 at 1 mg·mL-1 demonstrated significant inhibition activity against Rhizoctonia solani with 9.25 mm of inhibition zone.Insecticidal and antimicrobial metabolites were purified by bioassay guided fractionation,and further obtained monomeric compounds,and the chemical structure was established by the analysis of 1H NMR data.The results suggested that these compounds all belonged to trichothecene mycotoxins.According to morphology and cultural characteristics and ITS1-5.8S-ITS2 sequence analysis,the strain Hmp-F73 was identified as Myrothecium verrucaria.