内生菌HT5产生抗菌物质培养基及发酵条件优化

Optimization of Culture Medium and Fermentation Conditions for Production of Antimicrobial Substance by Endophytes HT5

内生菌HT5发酵无菌滤液对番茄早疫病菌的菌丝生长和孢子萌发均有强烈的抑制作用。试验以内生菌HT5发酵液无菌滤液对番茄早疫病菌的抑菌活性作为优化指标,测定菌株HT5产生抗菌物质培养所需的碳源、氮源、无机盐,并通过均匀试验对菌株产生抗菌物质的培养基配方进行了优化,同时利用正交试验对菌株产生抗菌物质的发酵条件进行了优化。结果表明,菌株HT5产生抗菌物质的最佳碳源、氮源和无机盐分别为葡萄糖、酵母浸膏和硫酸镁;最优培养基组合配方为:葡萄糖22.3 g/L,酵母浸膏29.9 g/L,硫酸镁5 g/L;最佳发酵条件组合为:温度28℃,接种量4%,pH值6.5,转速150 r/min,装液量50 mL,培养时间6 d。

Aseptic filuate of endophytes HT5 show strong inhibition on mycelial growth and spore generation of Alternaria solani,therefore in this experiment,with antibacterial activity on Alternaria solani of aseptic filtrate as optimizing index,the effect of carbon,nitrogen sources and salts on the production of antimicrobial substances of strain HT5 was studied,the medium composition was optimized by uniform experiment and fermentation conditions were optimized by orthogonal experiment.The result showed that the optimal carbon source,nitrogen source and salt were glucose,yeast extract and MgSO4·7H2O respectively.The composition of the best medium was 22.3 g/L sucrose,29.9 g/L yeast extract,5 g/L MgSO4·7H2O.The optimal fermentation conditions were the combination of temperature 28 ℃,4％ inoculums,initial pH 6.5,speed 150 r/min,liquid volume 50 mL,incubation time 6 d.