秸秆污泥堆肥产纤维素酶细菌的筛选及产酶条件优化

从添加秸秆进行堆肥处理的污泥中采集样品,通过富集培养和刚果红平板染色法筛选分离出具有纤维素降解能力的细菌,再通过酶活力测定从中分离筛选出1株相对高活性的产纤维素酶细菌CI;通过基于16S rRNA基因序列的系统发育分析,初步确定该菌株为Devosia sp..利用单因素试验对目的菌株C1进行产纤维素酶发酵条件优化,结果表明菌株C1产纤维素酶的最佳发酵时间、培养温度、摇床转速以及最适初始pH值分别为60 h、30℃、130 r·min^-1和7.2～7.5,且在该条件下其滤纸酶（FPase）和羧甲基纤维素酶（CMCase）活力分别达23.10和54.97 U·mL^-1.

Screening of Strains of Cellulase-Producing Bacteria in Compost of Sewage Sludge and Straw and Optimization of Cellulase-Producing Conditions.

Samples collected from compost of sludge and straw were incubated for enrichment culture,and then strains of bacteria capable of decomposing cellulose were screened out with the Congo red staining plate method.Enzyme activities of the stains of bacteria were measured and one strain,relatively higher in cellulose-producing activity,was isolated as C1.Phylogenetic analysis based on 16S rRNA gene sequences revealed that the isolated strain of bacteria,C1,was preliminarily identified as Devosia sp.Single factor experiments were adopted to optimize the fermentation conditions for C1.Results show that for C1,60 hours of incubation at 30 ℃ with the culture medium being in the range of 7.2-7.5 in initial pH in the shaker rotating at a rate of 130 r · min^-1 was the optimal cellulase-producing condition.Under such conditions,the activities of filter paper enzyme （FPase） and carboxymethyl cellulase （CMCase） produced by Strain C1 reached 23.10 and 54.97 U · mL^-1 respectively.