Numerous studies have evaluated the toxicity and endocrine disrupting properties of organic UV filters for aquatic organisms,but little is known about their biodegradation in river sediments and their impact on microo...Numerous studies have evaluated the toxicity and endocrine disrupting properties of organic UV filters for aquatic organisms,but little is known about their biodegradation in river sediments and their impact on microorganisms.We have set up the sterile and microbiological systems in the laboratory,adding 2-ethylhexyl-4-methoxycinnamate(EHMC),one of organic UV filters included in the list of high yield chemicals,at concentrations of 2,20 and 200μg/L,and characterized the microbial community composition and diversity in sediments.Monitoring of EHMC degradation within 30 days revealed that the half-life in the microbial system(3.49 days)was much shorter than that in the sterile system(7.55 days).Two potential degradation products,4-mercaptobenzoic acid and 3-methoxyphenol were identified in the microbial system.Furthermore,high-throughput 16s and 18s rRNA gene sequencing showed that Proteobacteria dominated the sediment bacterial assemblages followed by Chloroflexi,Acidobacteria,Bacteroidetes and Nitrospirae;Eukaryota_uncultured fungus dominated the sediment fungal assemblages.Correlation analysis demonstrated that two bacterium genera(Anaerolineaceae_uncultured and Burkholderiaceae_uncultured)were significantly correlated with the biodegradation of EHMC.These results illustrate the biodegradability of EHMC in river sediments and its potential impact on microbial communities,which can provide useful information for eliminating the pollution of organic UV filters in natural river systems and assessing their potential ecological risks.展开更多
基金supported by the National Natural Science Foundation of China(Nos.51879228,51769034)the National Science Funds for Creative Research Groups of China(No.51421006)the Priority Academic Program Development of Jiangsu Higher Education Institutions。
文摘Numerous studies have evaluated the toxicity and endocrine disrupting properties of organic UV filters for aquatic organisms,but little is known about their biodegradation in river sediments and their impact on microorganisms.We have set up the sterile and microbiological systems in the laboratory,adding 2-ethylhexyl-4-methoxycinnamate(EHMC),one of organic UV filters included in the list of high yield chemicals,at concentrations of 2,20 and 200μg/L,and characterized the microbial community composition and diversity in sediments.Monitoring of EHMC degradation within 30 days revealed that the half-life in the microbial system(3.49 days)was much shorter than that in the sterile system(7.55 days).Two potential degradation products,4-mercaptobenzoic acid and 3-methoxyphenol were identified in the microbial system.Furthermore,high-throughput 16s and 18s rRNA gene sequencing showed that Proteobacteria dominated the sediment bacterial assemblages followed by Chloroflexi,Acidobacteria,Bacteroidetes and Nitrospirae;Eukaryota_uncultured fungus dominated the sediment fungal assemblages.Correlation analysis demonstrated that two bacterium genera(Anaerolineaceae_uncultured and Burkholderiaceae_uncultured)were significantly correlated with the biodegradation of EHMC.These results illustrate the biodegradability of EHMC in river sediments and its potential impact on microbial communities,which can provide useful information for eliminating the pollution of organic UV filters in natural river systems and assessing their potential ecological risks.