黄粉甲幼虫抗菌物质的诱导及其抗菌活性

Inducement and production of antibacterial substances in Tenebrio molitor larvae and their antibacterial activity

采用饥饿法、紫外线照射法和针刺法处理黄粉甲Tenebriomolitor 6龄幼虫后均能诱导其产生抗菌物质 ,收集的血淋巴上清液对真菌有抑制作用 ,对细菌无抑制作用 ;经热处理后的血淋巴上清液则对细菌有抑制作用 ,而对真菌无抑制作用。SDS PAGE检测结果发现 ,与未诱导的对照相比经诱导的黄粉甲幼虫血淋巴中 ,原有的一类大分子蛋白质如分子量分别为 97kD、4 4kD和 37kD左右的蛋白质缺失 ;而ESI MS分析结果显示诱导后比诱导前黄粉甲幼虫血淋巴中有小分子物质产生 ,推测可能是此类缺失蛋白质分解为小分子量的抗菌肽 ,从而表现出抗菌活性。

Sixth-instar larvae of Tenebrio molitor were treated with different inducing methods including starving, radiating with ultraviolet and pricking, and they all could induce the production of antibacterial substances in hemolymph. The supernate of induced hemolymph not treated with heat had inhibitive effect on fungi, but had no effect on bacteria. When the induced hemolymph was heated, the supernate had inhibitive effect on bacteria, but had no effect on fungi. The result of SDS-PAGE showed the original macromolecular proteins, such as those with molecular weights of 97 kD, 44 kD and 37 kD, disappeared in the induced hemolymph compared with the uninduced one. Moreover, the results of ESI-MS showed micromolecular substances appeared in the hemolymph of the T. molitor larvae after induction. It was inferred that the disappeared proteins decomposed to micromolecular antibacterial peptides with bactericidal activity.