抗生素废水批量处理的pH调控及其影响

Control of Microbial Communities Achieved by pH Adjustment and Its Influences on Batch Treatment of Antibiotic Wastewater

在不同pH水平下进行了抗生素废水的批量处理,试验结束时利用扫描电镜（SEM）、荧光原位杂交-流式细胞术联用技术（FISH-FCM）分析了不同pH条件下获得的降解菌群中酵母和细菌的构成,基于Biolog方法比较了不同降解菌群的代谢多样性,并考察了降解菌群构成的变化对抗生素废水批量处理效果的影响.结果表明,批量处理过程的pH调控显著影响了降解菌群中酵母和细菌的比例,并进而影响了废水处理效果.当批量处理过程的pH值分别控制在4～5、5～6、6.5～7.5时,降解菌群中酵母构成比例分别达到88.20%5、4.43%、1.75%,同时细菌的构成比例相应呈逆向变化;Biolog FF微平板分析表明,3种pH条件下的降解菌群具有类似的代谢多样性,但酵母占优势时降解菌群的代谢活性较低;随着酵母比例的下降或细菌比例的上升,批量处理的COD去除率分别为34.8%4、4.8%和61.2%.

Scanning electron microscope （SEM）, Fluorescent in-situ hybridization （FISH）-Flow Cytometry （FCM） as well as Biolog method were used to discuss the effect of pH control during the batch treatment on the composition and catabolic diversity of the microbial communities obtained from antibiotic wastewater. The following results were obtained： ① At the end of batch treatment, the percentages of yeast cells in three cultures amount to 88.20% , 54.43% and 1.75% , respectively, when pH levels are individually maintained at 4 ～ 5, 5 ～ 6 and 6.5～ 7.5 throughout three batch experiments. Correspondingly, the percentages of bacterial cells in three cultures increase with the increase of pH levels. ② No significant differences are found among the catabolic diversity of three cultures while the yeast-predominant culture has slightly less catabolic activities in Biolog FF microplate. ③ When bacteria gradually develop to be the dominant species in the culture, gradually enhanced COD removals of 34.8% , 44.8% and 61.2%, respectively, are achieved.