利用T-RFLP解析生物强化去除吡啶过程中微生物种群动态变化

在接种活性污泥处理含吡啶废水的序批式反应器中,引入吡啶降解菌Paracoccus sp.KT-5构成生物强化反应器,研究了对吡啶的生物强化去除特性及效果,利用末端限制性片段长度多态性(T-RFLP)手段解析了微生物种群结构的动态变化.结果表明,投加高效降解菌株KT-5可以加速反应器的启动,但随着反应器的运行,当吡啶初始浓度增加至195.6 mg·L^-1以后,生物强化反应器对吡啶降解的促进作用已不再明显;当吡啶初始浓度在293.4~586.8 mg·L^-1变化时,起初强化反应器对吡啶的去除速率出现了波动,尽管随后逐渐恢复,但仍然没有表现出明显的强化作用.T-RFLP的分析结果表明,当吡啶初始浓度达到978 mg·L^-1以后,生物强化反应器中已检测不到KT-5,表明生物强化作用的消失可能是因为引入的高效降解菌株KT-5的流失造成的.

The analyses of microbial community dynamics by T-RFLP during the bioaugmented removal of pyridine in SBR

A bioaugmented reactor was developed through the introduction of Paracoccus sp. KT-5 into a sequencing batch reactor inoculated with activated sludge to treat pyridine-containing wastewater. The microbial community dynamics were analyzed by terminal restriction fragment length polymorphisms (T-RFLP) to evaluate the bioaugmentation effect. The results showed that the introduced strain KT-5 could accelerate the start-up of the SBR, in comparison with the non-bioaugmented one. However, the enhancing effect of bioaugmentation on pyridine degradation was not significant when the initial pyridine concentration increased to 195.6 mg·L^-1. Moreover, the removal rate of pyridine was fluctuated when the initial pyridine concentration varied in the range of 293.4~586.8 mg·L^-1. The analyses of T-RFLP showed that the introduced Paracoccus sp. KT-5 did not exist in the bioaugmented reactor when the initial pyridine concentration reached 978 mg·L^-1, indicating that wash-out of strain KT-5 was probably responsible for the failure of bioaugmentation.