活性污泥对微藻聚集影响及细菌群落响应研究

针对微藻收集问题，文章以小球衣藻（Chlamydomonas microsphaera）为研究对象，探究活性污泥细菌对微藻聚集的影响和微藻聚集对污泥细菌群落结构的影响，揭示菌藻聚集体形成机制。结果表明：污泥细菌的出现能显著促进小球衣藻的聚集，其聚集率随着污泥细菌数量的增加而上升，混合培养时小球衣藻聚集率比纯培养时（聚集率为12.94%）有较大提升，在藻菌细胞数量比为1：10时，聚集率可达62.92%；菌藻体系中菌藻聚集体的胞外聚合物（extracellular polymeric substances，EPS）分泌量比纯培养微藻上升约163.38 mg/L。对污泥细菌种群变化的分析显示，假单胞菌属Pseudomonas和根瘤菌属Rhizobium在促进小球衣藻聚集方面发挥着重要的作用。

To address the issue of microalgae harvesting, this study took Chlamydomonas microsphaera as the research subject to investigate the effect of activated sludge on microalgae aggregation and the impact of microalgae aggregation on the bacterial community structure of the sludge, thereby revealing the mechanisms underlying the formation of bacterial-algal aggregates. The results showed that the presence of sludge bacteria significantly promoted the aggregation of Chlamydomonas microsphaera and its aggregation rate increased with the increase of the number of sludge bacteria. The aggregation rate of Chlamydomonas microsphaera in mixed culture was higher than that in pure culture (12.94%), and the aggregation rate could reach 62.92% at the ratio of algae to bacteria of 1:10. At the same time, the extracellular polymeric substances (EPS) secretion of the bacterial-algal aggregates increased about 163.38 mg/L compared to the pure culture of microalgae. Analysis of the population change of sludge bacteria showed that Pseudomonas and Rhizobium played an important role in promoting the aggregation of Chlamydomonas microsphaera.