Physiological And Biochemical Effects Of Organic Toxicants On Algae And Protemics Study

Since the industrial revolution, there has been a dramatic increase in the production of synthetic organic chemicals. The majority the synthetic organic chemicals have been released into the water bodies, which have posed significant threat to the aquatic ecosystems. Nitrobenzene and aniline are the common used industrial material, which are highly toxic and widely distributed and listed as priority pollutant by American EPA and China EPA. Algae is the important member in aquatic ecosystem as primary producer and oxygen generator, and has a great biomass in the environment. It is therefore the study about the effects of pollutants on algae and the biotransformation of pollutants by algae is important for the risk assessment of pollutants in the aquatic environment.Four species of typical freshwater algae—Euglena gracilis, Chlamydomonas reinhardtii, Navicula pelliculosa and Synechococcus leopoliensis were selected as the experiment materials. Effects of nitrobenzene on the growth and chlorophyll a content of the algae, the biodegradation and bioaccumulation of nitrobenzene, and the response of antioxidant enzymes to nitrobenzene were investigated, in order to reveal (a)the toxicity of nitrobenzene to algae(b)the biodegradation and bioaccumulation of nitrobenzene in algae (c)the relationship between the resistance of algae against nitrobenzene and antioxidant enzymes. The results indicated that the growth and chlorophyll a in the four species of algae showed similar response to nitrobenzene, the order of resistance were E. gracilis> C. reinhardtii > N. pelliculosa > S. leopoliensis. No significant biodegradation and bioaccumulation of nitrobenzene were found in the four species of the algae. The resistance of the algae against nitrobenzene mainly rely on the antioxidant system. SOD played the most important role and POD also showed functions in the resistence mechanism in the algae.Chlamydomonas reinhardtii is a eukaryotic model organism. It was found that the C reinhardtii was able to degrade aniline and cytochrome P450 played important role in the biodegradation pathway previously in our lab. Since cytochrome P450s locate on microsome, In order to reveal the cytochrome P450 which involved in the biodegradation of aniline, the paper analysied the expression change of microsome proteins by proteomics method. Ttwo-dimensional electrophoresis was applied and got the 2-D map...