Bioaccumulation And Biodegradation Of Several Organic Pollutants By Microcystis Aeruginosa And Chlorella Ellipsoidea

Microalgae,as a kind of ubiquitous organisms,is not only important to the stability of the ecological environment,but also plays an important role in the removal of environmental pollutants.Its ability about removal of environmental pollutants,especially for the removal of persistent organic pollutants(POPs),is causing more and more attention.Microalgae can remove POPs not only though adsorption,accumulation and degradation,but also producing oxygen or active oxygen to improve degrading-ability of some bacteria or enhancing photo degradation of pollutants.Research about accumulation and degradation of organic pollutants by algae can provide not only a method to remove pollutants,but also basis of evaluating behavior and fates of pollutants in environment.In this study,Microcystis aeruginosa,a kind of dominant algae in eutrophication water,and Chlorella ellipsoidea,which is widely used in production life,are selected as experimental organisms.Their removal effects of two common organic pollutants-BPA and acetaminophen,are studied,and influencing factors including concentration range of pollutants,nutrition conditions and initial algae concentration to removal efficiency are also explored.Results are as follows:(1)Microcystis aeruginosa 918 can remove BPA and acetaminophen to some extent.BPA and acetaminophen of 1,5,10 mg/L decreased 39%,12%,9%and 22%,7%,13%after 10 days' treatment with algae,respectively.BPA concentrations in algae increased with initial concentration added in the medium,so did acetaminophen concentrations.Two possible degradation products of BPA in Microcystis aeruginosa 918 were identified as 4-Ethylphenol and 2,6-Dihydroxybenzoic acid;(2)Microcystis aeruginosa 1343 can remove BPA and acetaminophen to some extent,but effects were not evident.BPA and acetaminophen of 1,5,10 mg/L decreased 6%,6%,12%and 14%,9%,9%after 10 days' treatment with algae,respectively.BPA concentrations in algae increased with initial concentration added in the medium,and showed rising trend during the experiment.Acetaminophen concentration in algae that treated with lmg/L was stable,while groups treated with 5mg/L and 10mg/L showed rising trend during the experiment;(3)Chlorella ellipsoidea can remove BPA and acetaminophen to some extent.BPA and acetaminophen of 1,5,10 mg/L decreased 10%,8%,2%and 18%,15%,18%after 10 days' treatment with algae,respectively.BPA concentrations in algae increased with initial concentration added in the medium and showed rising trend during the experiment,acetaminophen concentrations in algae showed increase and then decline in groups treated with 1 mg/L and 5 mg,/L,while it showed reverse trend for groups treated with 10mg/L.Three possible degradation products of BPA were identified as 4-Hydroxy-3-methoxybenzaldehyde,4-Ethylphenol and 2,6-Dihydroxybenzoic acid;(4)Pollutant concentration range and initial algae concentration influenced the removal efficiency to some extent,while nutrition conditions did little.Acetaminophen of 10,50,100ug/L and 15,30,50mg/L decreased 10%,31%,17%and 5%,10%,10%after 10 days' treatment with Chlorella ellipsoidea,respectively.Initial algae concentration influenced the removal efficiency significantly,the highest removal efficiency reached 22%while the lowest was 5%.