Effect Of Nonylphenol To Microbial Flora In The Wasterwater Treatment

Environmental endocrine disruptors nonylphenol (NP) are a common contaminantin industrial wastewater, which is widely found in the wastewater treatment system,and easy to produce cumulative effect. Biodegradation of NP may occur in thelong-term accumulation of organic matter in the reactor, and it is difficult to solve theabnormity during ammonia nitrogen wastewater treatment process. By the use ofmicrobial ecology,we can detect the process of biological degradation mechanism,including the structure of microbial flora involved in the biological treatment and themain function of the microbial flora to solve this problem. It is gradually become a hotresearch both at home and abroad.In this study, we use some molecular biology techniques, such as PCR-DGGE and454pyrosequencing to detect changes of microbial community structure, diversityindex and advantages genus. The exploration of research aimed at the effect caused bythe presence of different concentrations of NP to the wastewater treatment system atlevel of molecular biology.The research results showed that, with increasing concentration of NP,total nitrogen and total organic carbon removal effect became gradually worse in the SBRreactor, and removal rate reached the lowest when NP dosing concentration of80mg/L.DGGE analysis of sludge samples showed that some bands brightness graduallyreduced with increasing NP concentration while others gradually deepened. Somemicrobial communities in the system could not adapt to the high concentration of NPso the abundance gradually reduced. With the deepening of the domesticated process,some newborn communities which may have a strong ability to degrade and adapt thisenvironment formed.454sequencing data showed that the change of diversity index experienced adecrease after the first increase. And there was a abundance decrease with the increaseof NP concentration in Nitrobacter sp. during nitrification period, Paracoccusdenitrificans and Nitrosomonas sp. during denitrification period, as well as theircommon advantage function flora Thauera sp.. But the abundance ofPseudoxanthomonas sp. and Acidovorax sp. increased slightly in the highconcentration of NP acclimation period, some of which may play an important role inthe degradation of NP.