高效木质素降解菌的筛选及降解性能研究

【目的】筛选纯化及鉴定木质素降解菌,对其降解性能进行初步研究。【方法】从某制浆造纸厂的造纸废水污泥中,筛选获得2株具有木质素降解能力的细菌LD-1和LD-2。通过形态观察和16SrRNA序列分析对菌株进行鉴定;采用苯胺蓝平板脱色法及以TC为指标分别定性定量测定2株细菌的木质素降解能力。【结果】LD-1和LD-2分别被鉴定为Sphingobacterium属和Bacillus属的菌株,命名为Sphingobacterium sp.LD-1和Bacillus sp.LD-2。通过苯胺蓝平板脱色实验,发现LD-1和LD-2均具有良好的木质素降解能力。经测定,两株菌种发酵7d对木质素的降解率分别达到52.23%和50.36%。【结论】成功筛选到2株能高效降解木质素的菌株LD-1和LD-2。

Screening of High Active Lignin-degrading Strains and the Measurement of Their Lignin Degradation

Objective] This study focused on screening, isolating and identifying lignin-degrading strains, and studying on their lignin degradation.Methods] Two lignin-degrading bacterial strains (LD-1, LD-2) were isolated from the effluent sludge of a pulp paper mill, and identified by morphological observation and 16S rRNA sequence analysis.Their activity of lignin degradation were measured qualitatively and quantitatively by using plate culture medium with Azure-B and TC index, respectively.Results] LD-1 and LD-2 were characterised as Gram negative small rod and Gram positive rod.Further, 16S rRNA sequencing showed 99% base sequence homology to Sphingobacterium and Bacillus, and the two strains were finally designated as Sphingobacterium sp.LD-1 and Bacillus sp.LD-2, respectively.LD-1 and LD-2 showed potential of lignin degradation by using plate culture medium with Azure-B.Moreover, the lignin degradation by these two bacterial strains reached 52.23% and 50.36%, respectively, within 7 days.Conclusion] LD-1 and LD-2 showed high activity of lignin degradation.