低温沼气发酵优良菌系筛选及优势菌群分析

Screening and dominant population analysis of microbial strains in biogas fermentation under the low temperature

摘要:

【目的】为获得低温沼气发酵高效菌系, 从张家口、承德和邯郸地区采集低温产气良好的沼气池中沼泥样品12份。【方法】以沼泥为接种源进行16 °C?5 °C阶段降温模拟沼气发酵试验, 对处理组HL2、ZG2、CW1及其相应的接种源HLA、ZGB、CWB进行DGGE分析。【结果】ZG2处理组模拟沼气发酵综合性能最优, 与其他处理组呈显著性差异; DGGE图谱显示, 被检测样品中古菌种属多样性丰富, 但图谱中代表优势种属条带的位置存在较大差异。通过16S rDNA克隆及测序分析, 样品中主要优势菌属为甲烷八叠球菌属、甲烷鬃毛菌属和甲烷粒菌属。【结论】DGGE图谱中代表甲烷八叠球菌属的条带是样品ZG2和ZGB中唯一重复出现的条带, 且未作为优势条带出现在其他样品中, 推测甲烷八叠球菌属与低温产沼气有密切相关性。

Abstract:

[Objective] To obtain the best produce methane of microbial strains, twelve biogas slurry samples were collected from the biogas digesters in Zhangjiakou, Chengde and Handan. [Methods] Biogas fermentation experiment were produced with different biogas slurry samples by decreasing the operating temperature form 16 °C to 5 °C. DGGE analysis was taken on samples (HL2, ZG2, CW1, HLA, ZGB and CWB). [Results] The results showed the ZG2 with biogas yield, gas-production rate and methane content were significantly superiority at the same temperature stage among the inoculation treatments. In addition, DGGE chart were observed that there were abundant microbial diversity and it was significantly different bands among the dominant archaea. Through 16S rDNA cloning sequencing analysis, the dominant archaea were composed of Methanosarcina, Methanosaet and Methanocorpusculum in the samples. [Conclusion] Furthermore, Methanosarcina major existed only in ZG2 and the same dominant archaea as ZGB. In conclusions, Methanosarcina were closely related to effectively gas under low temperature condition.