枯草芽孢杆菌菌种退化及其控制

A Study on Strain Degeneration and Its Control of Bacillus subtilis

以枯草芽孢杆菌 (Bacillussubtilis)的生物量、拮抗效应下降为菌种退化的标志 ,研究了 2个菌株 (BS - 3,PRS5 )在不同培养基上及继代培养过程中的退化现象 ,同时探讨了 5种载体、不同复壮时间对恢复B .subtilis生物量及拮抗效应的影响 ,结果显示 :枯草芽孢杆菌 (B .subtilis)在常见的 7种培养基中以营养贫乏的PDA ,WPA ,CMA最易发生退化 ,SDAY较为稳定 ,两菌株中 ,BS - 3退化速度慢于PRS5 ;在供试的 5种复壮载体中 ,以“灭菌土 + 1 %蛋白胨 + 1 %葡萄糖 + 0 5 %酵母浸膏”为最佳 ,且BS - 3的复壮速度慢于PRS5 ,分别为 1 2 0d和 90d .

The degeneration of 2 strain (BS-3 and PRS5) in various media and subculturing was studied with the decrease of antagonism and biomass of Bacillus subtilis as the degenerations token,and then effects of 5 carriers and rejuvenescert time on the restoration of the biomass and antagonism for B.subtilis were also explored.Of the seven regular media, B.subtilis most stably grew on SDAY,but those nutrition poor ones such as PDA,WPD,CMA caused degeneration frequently,the degenerations rate of BS-3 was slower than that of PRS5.Among 5 rejuvenescent carriers,the carrier which contained steriled soil,1% peptone,1% glucose and 0.5% yeast abstract was regarded as the best one.In rejuvenescent rate,PRS5 was 90 days and 120 days faster than BS-3 respectively.