一种微生物絮凝剂产生菌筛选 鉴定及应用-screening, identification and application of microbial flocculant-producing bacteria.docxVIP

II II 物絮凝剂样品投加量为 2mL；助凝剂 CaCl2 溶液的最佳投加量为 4mL； 宜选用 Ca2+作为最佳金属离子助凝；菌株 M2 絮凝剂的热稳定性不好， 絮凝剂的主要成分可能为蛋白质。对菌株 M2 絮凝剂的应用进行初步 研究，得到其能快速絮凝土壤悬浮液，絮凝颗粒大且紧实，絮凝率可 达到 96%；菌株 M2 絮凝剂同样能有效絮凝木薯淀粉废水，絮凝率为 63%，COD 去除率为 66%。菌株 M2 能有效使用木薯淀粉废水作为 廉价培养基。 关键词：微生物絮凝剂 克雷伯氏杆菌 培养条件 生长特性 絮凝性能 III III THE SCREENING, IDENTIFICATION AND APPLICATION OF A BIOFLOCCULANT-PRODUCING ABSTRACT More and more attention has been attached to microbial flocculants for their advantages, which includes high efficiency, non-toxic and harmless, no secondary pollution, etc. To screen out predominant strain is the first step to get efficient microbial flocculants, and then research on the culture conditions and flocculation performance can do some help by playing a guiding role in their industrial application. 33 of pure strains were screened out from Cassava starch yellow pulp wastewater by means of the common bacteria screening and purification method, then 5 strains with flocculating activity were screened out through preliminary screening. And then through further screening, one high-efficiency microbial flocculent producing bacteria was screened out, which was named Klebsiellasp.M2 after morphological features, physiological and biochemical reaction experiments and 16 s rDNA gene sequence analysis confirming the strain was Klebsiella. The strain M2 culture condition was optimized and growth characteristics was researched by single factor experiment. The results showed that, the best culture medium type, medium initial pH range and table speed were Chavez medium, 4-7 and 140r/min respectively. The IV IV best carbon source and nitrogen source for the strain M2 were sucrose and KNO3. The strain M2 is well adapted to both acid and alkali environment, it was good for the bacteria to produce flocculants in 30℃, and good for bacteria somatic breeding in 25℃. The flocculating activity of strain M2 is distributed in bacteria itself. It had the advantages of easy to be stored, transported and used. And under