斜纹夜蛾抗菌物质的诱导及其理化特性

Induction and Characterization of Antibacterial Substance of Spodoptera litura

用大肠杆菌K12D31免疫斜纹夜蛾六龄幼虫,12h后收集血淋巴并通过高温处理制成粗提液。SDS-PAGE电泳结果表明:诱导后粗提液含有3条分别为43.5、15.0、4.0kD的特异性条带。诱导产生的抗菌物质在酸性、高温和常温等条件下保持稳定。抗菌谱测定结果表明,诱导产生的抗菌物质对猪霍乱沙门氏菌、枯草芽孢杆菌、铜绿假单胞菌等革兰氏阴性和阳性菌有抑制作用,而且对白色念珠球菌、酿酒酵母也有抑制作用。

By injection of Escherichia coli K12D31 into 6th instar larvae of Spodoptera litura, antibacterial substances were induced in haemolymph of the larvae after 12 h. SDS-PAGE analysis indicated that there were three bands with molecular weight 43.5, 15.0 and 4.0 kD, respectively, in the antibacterial crude extract. Characterization of the antibacterial substances showed that the induced antibacterial substances kept high stability under acid condition, a short- time exposure to heating and room temperature. The antibacterial substances were also inhibitive to Candida albicans and Saceharomyces cerevisiae, besides Salmonella choleraesuis subsp, choleraesuis, Bacillus subtilis and Pseudomonas aeruginosa, and other bacteria.