中文摘要：

为了防止水果采后青霉病的发生及青霉毒素带来的危害,本实验以扩展青霉（Penicillium expansum 3.3703）为指示菌,采用平板对峙法和双层平板琼脂扩散法筛选得到1株来源于乌龙茶的LPL-T12菌株,其发酵上清液抑菌圈直径达（22.74±0.44）mm。菌株经形态学观察、生理生化实验、16S rDNA序列及特异性PCR分析可知,LPL-T12菌株为解淀粉芽孢杆菌（Bacillus amyloliquefaciens）。菌株发酵液通过硫酸铵沉淀及不同孔径透析袋截留后,粗提物经抑菌活性检测、蛋白酶及热处理分析可知,该抗菌物质为分子质量在8000D以上的热敏感蛋白类物质。

英文摘要：

In order to obtain a Bacillus spp.that can protect post-harvest fruits from blue mould and patulin,plate confrontation test and double layer agar diffusion method were used for strain screening in this study.The Bacillus strain LPL-T12 isolated from oolong tea exhibited the best antibacterial effect,whose fermentation supernatant had an inhibitory zone diameter of（22.74 ± 0.44） mm against Penicillium expansum 3.3703.In addition,LPL-T12 was identified as Bacillus amyloliquefaciens through morphological observation,physiological and biochemical experiments,16S rDNA sequence analysis and specific PCR amplification.After the fermentation supernatant of the strain was subjected to ammonium sulfate precipitation and dialysis against several different pore-size membranes,a thermosensitive protein with molecular weight of more than 8000 D was obtained based on antibacterial activity analysis,protease hydrolysis and heating treatment.