关键词: 淡色生赤壳菌, 抑菌活性, 稳定性, 分离

Abstract: Bionectria Ochroleuca YLZ42 was isolated from the soil in Yulin of Guangxi Zhuang Autonomous Region;  and this strain yielded active metabolite exhibiting strong inhibition on Bacillus cereus. This paper used Bacillus cereus as bioassay indicator to study the activity characteristics of the antibacterial metabolite in the broth. The results indicated that the antibacterial activity was stable in 40~60℃ and lost less than 7% at 60℃ for 1 h; the antibacterial activity was also stable under pH 2~7, but it would loss dramatically when pH was greater than 7, for instance 64% of the antibacterial activity was lost under pH 8 for 12 h. The broth should be stored in the acidic conditions because only 5% of the antibacterial activity was lost under pH 4 for 15 d. Besides, the antibacterial metabolite was not sensitive to UV and it could keep the activity under UV radiation for 24 h. Antibacterial compound was isolated and purified by means of extraction, TLC, HPLC and its molecular weight was 513, which was different from those active metabolites reported in the relevant literatures.

Key words: Bionectria ochroleuca, antibacterial activity, stability, isolation