Construction Of Algal-bacterial Consortiums And Its Degradation Effect Of Nonylphenol

Nonylphenol(NP)is the raw material for the synthesis of nonionic surfactant nonylphenol polyethoxylates(NPEOs).It is extensively used in industrial and agricultural production,and in daily life.However,when it is released into the environment,especially aquatic ecosystems,will polluted and hazarded to aquatic organisms.NP is a typical environmental hormone contaminant,with obvious estrogenic effects and strong bioaccumulation effects.Once entering the aquatic ecosystem,can cause a potential hazard to human health and ecosystem safty.Therefore,exploration of bioremediation technologies and methods for environmental hormone-contaminated waters has become an important task in the ecological field.In this study,the construction of algal-bacterial consortiums and its degradation characteristics of nonylphenol were carried out,with the purpose of bioremediation of NP-polluted aquatic ecosystems.The results showed that:(1)Four microalgae have the capability of adsorption,absorption and degradation with nonylphenol were selected.There are Phaeocystis globosa,Nannochloropsis oculata,Dunaliella salina and Platymonas subcordiformis.The removal efficiency(including adsorption rate,absorption rate and degradation rate)of nonylphenol was 47.18%-96.36%(average removal efficiency is 73.36%)for four microalgae,and the degradation percentage was 43.43%-90.94%(average biodegradation percentage is 69.38%).NP removed and degradated by P.subcordiformis is the most significant.(2)A strain of efficiently degrading NP,Sphingomonas sp.,was selected.This strain can grow well with the four microalgae in the same culture medium,respectively.The removal efficiency of NP(10 mg/L)was 84.20%,the degradation percentage of strains to NP was 14.82% higher than the average degradation percentage of four microalgae.In the experiment of co-cultivation of algae and bacterial,four microalgae were combined with Sphingomonas sp.to form different proportions of algal-bacterial consortiums,all of which could grow well together.P.globosa-B,N.oculata-B,D.salina-B and P.subcordiformis-B were observed to have higher chlorophyll a content than microalgae alone at the ratios of 4:1,2:1,4:1 and 1:1.(4)Constructed four algal-bacterial consortiums: P.globosa-B,N.oculata-B,D.salina-B,and P.subcordiformis-B.Four algal-bacterial consortiums exposed to NP(2 mg/L)in 168-h,the removal efficiency for NP were 79.96%,74.56%,78.40%,and 78.14%,respectively.The degradation of NP by algal-bacterial consortiums was generally better than that of microalgal,howerver,its degradation percentage to NP was lower than that of bacterial.