基于PCR-TGGE技术的餐厨垃圾厌氧消化微生物群落结构解析

为了解不同负荷下单相餐厨垃圾厌氧消化反应器内微生物群落结构演替特征,在单相厌氧消化反应器负荷为2.0～8.5kg·m-·3d-1(以VS计)的不同负荷条件下取样,运用16SrDNA的PCR-TGGE技术对反应器内微生物进行动态追踪.同时,运用Dice系统和NMDS软件对PCR-TGGE图谱进行分析.结果表明,负荷为4.0～6.0kg·m-·3d-1时,微生物群落结构变化不大;负荷为6.0～7.0kg·m-·3d-1时,微生物群落结构变化较为明显;负荷分别为7.0～8.0kg·m-·3d-1及8.5kg·m-·3d-1时,微生物群落结构变化最为明显.纵观整个过程,在餐厨垃圾厌氧消化反应器有机负荷在2.0～8.5kg·m-·3d-1下厌氧反应器内的微生物群落结构存在明显的阶段性演替;负荷为7.0kg·m-·3d-1时微生物群落结构的丰富度最好.

Analysis of microbial community structure in anaerobic digestion of food waste by PCR-TGGE

The objective of this study was to better understand the transition of microbial communities during the anaerobic digestion (AD) of food waste at different volumetric organic loading rates. Tests were conducted in laboratory scale, single-phase reactors operated at loading rates ranged from 2.0 to 8.5 kg·m^-3·d^-1. The microbial community structure and dynamics were characterized by the 16S rDNA-based polymerase chain reaction-temperature gradient gel electrophoresis (PCR-TGGE) assay. The TGGE profiles analyzed by Dice similarity coefficients method and non-metric multidimensional scaling (NMDS) method indicated that the microbial community structure varied significantly at loading rates of 7.0~8.0 kg·m^-3·d^-1 and 8.5 kg·m^-3·d^-1, respectively, but insignificantly at the loading rate of 4.0~6.0 kg·m^-3·d^-1. In summary, significant phase transition in the microbial community structure occurred at the full range of 2.0 to 8.5 kg·m^-3·d^-1, with an optimal diversity of microbial communities observed at 7.0 kg·m^-3·d^-1.