胞外酶对堆肥中微生物群落演替的影响

研究了添加黄孢原毛平革菌胞外酶对农业废物堆肥中木质纤维素降解及微生物群落演替的影响.结果表明,堆肥初期,胞外酶对微生物生长具有抑制作用,且随堆肥时间的延长逐渐减弱;堆肥后期,胞外酶可提高微生物群落的多样性和均匀性,并促进木质素和半纤维素的大量降解.醌指纹数据显示,胞外酶并未引起新的优势醌的出现,进入高温期后,以MK-7为主要醌类的微生物作为优势菌群,且这种优势一直存在;堆肥后期胞外酶对甲基萘醌影响较大,可促进长链甲基萘醌的出现.主成分分析表明,胞外酶对醌种类演替的影响主要作用在3d和40d,这与非相似性指数结果一致,并使真菌在整个体系中影响力加大.

Influence of extracellular enzymes on microbial community's succession in composts

The effect of extracellular enzymes of Phanerochaete Chrysosporium on the lignocellulose degradation and the succession of microbial community in agricultural waste composts were studied. Extracellular enzymes had negative effect on total quinone content in the initial stage of composting, but this inhibitory effect decreased gradually along with the composting process. At the end of composting, the extracellular enzymes improved the diversity and evenness of the microbial community, and significantly increased the degradation amount of lignin and hemicellulose. The quinone profile showed that the bacteria indicated by MK-7 as major quinone were predominant after the mesophilic phase, and there was no new dominant microbe found in the composting with the enzyme additive. But extracellular enzymes had great positive effects on menaquinones and promoted the amount of long-chain menaquinones during the final phase of composting. The principal component analysis indicated that the greater effects of extracellular enzymes on the microbial community were observed on 3 d and 40 d than other days, which was consistented with the dissimilarities analysis result. In addition, the extracellular enzymes enhanced the effect of fungi in the whole system.