Toxic Effects Of6-APA On The Chara Braunii Gmel. And The Study On MBR Microbial Adaptability Of6-APA Wastewater

Penicillin can effectively control the disease,used widely,6-aminopenicillanic acid is the basic structure of Penicillin, is an import intermediate for the production of sime-synthetic β-lactam antibiotics. A large number of6-APA wastewater discharge causing serious pollution to the enviroment. Antibiotic contaminants removed from the environment mainly by biologicalmethod, activated sludge is an important part of the biological wastewater treatment process. The study of enzyme activity which catalyzed organic matter degradation and the diversity of microbial community structure of activated sludge process was significant to improve the effect of activated sludge process.In this paper, the toxicity effect of different concentrations of6-APA on Chara braunii, effect of6-APA on the activity of microbial community structure and enzyme in MBR were studied, the pollutant removal effect of different concentrations of6-APA under the conditions of MBR were investigated, the result were as follow:1.With the6-APA concentration increased, the relative plasmalemma permeability of Chara braunii was increased, the MDA of Chara braunii was reducing-increasing, SOD activity continue increasing, the POD of Chara braunii was increasing-reducing, Chlorophyll content was increasing-reducing.2.With the6-APA concentration increased, COD, BOD, the removal rate of6-APA and MLSS were significantly decreased, COD, BOD removal rate and MLSS concentration is highest in the influent of6-APA concentration was80mg·L-1, the highest removal rate of6-APA in the influent of6-APA concentration was60mg·L-1.3.With the6-APA concentration increased, the microbial enzyme activity of activated sludge change greatly, urease activity decreased, nitrate reductase, dehydrogenase, polyphenol oxidase activiy showed increasing trend, superoxide dismutase and invertase activity were increasing-reducing, the high concentration of6-APA has great effect on the microorganisms in activated sludge, can cause microbial activity decreased.4.With the6-APA concentration increased, the changes of microbial community structure is bigger, Catellibacterium sp.YW4、Uncultured bacterium clone AC24microbial gradually reduced, some can adapt to high concentration6-APA wastewater such as Tessaracoccus sp.SL014B-76A1、Uncultured gamma proteobacterium clone11-250has gradually become the advantage bacterium, become part of the stabilization period of microbial communities.In summary, when the concentration of6-APA was lower than60mg·L-1, can accelerate the Chara braunii growth, when the concentration of6-APA was higher than60mg·L-1, inhibited the Chara braunii growth and toxic effect on Chara braunii. Treatment6-APA waste water with the MBR reactor, gradually increased with the concentration of6-APA, the changes of microbial community structure and enzyme activity of activated sludge are larger, has certain adaptability for6-APA, the effluent quality can meet the national discharge standard of6-APA concentration was lower than100mg·L-1.