纤维素降解菌群TF18的作用机制

Mechanism of Cellulose Degrading Bacteria TF18

为进一步优化降解菌发酵条件和开发秸秆降解菌剂,以分离自自然腐烂玉米秸秆的纤维素降解菌群TF18为对象,研究该菌群的最佳培养条件及其作用机制。结果表明:TF18菌群是一个复杂的有机整体,最佳培养时间为72 h,最佳培养基为PD(马铃薯葡萄糖培养基)和KB,通过先分泌纤维素酶(CMC)和β-糖苷酶(β-Gase),再分泌全酶(FPA)和外切酶(C1)的方式达到降解秸秆的目的。通过纤维素酶活性与微生物类群酶活性的相关性分析得出放线菌群是分泌纤维素酶的主要微生物类群。TF18菌群发酵液与粉碎后的玉米秸秆混合8 d后玉米秸秆降解率可以达21.3%。因此,TF18菌群可以作为降解作物秸秆的目标微生物资源,进一步开发秸秆降解菌剂等产品。

In order to further optimize the fermentation conditions and develop straw degrading bacteria,the decomposing microflora TF18 isolated from natural decaying maize straw was studied in this study.The results showed that the decomposing microflora was a complex organic whole,and the suitable incubation condition was on PD and KB for 72 h.The purpose of straw degradation was achieved by secreting cellulase(CMC)and beta-glycosidase(beta-Gase)first and then total enzyme(FPA)exonuclease(C1).Moreover,actinomycetes were the main microbial groups secreting cellulase.The degradation rate of corn straw could reach 21.3%after 8 days of mixing TF18 fermentation broth with crushed corn straw.Therefore,the microflora TF18 could be candidate microorganism resources for straw decomposition agents.