高效絮凝菌的培养条件优化

SCREENING OF A FLOCCULANT PRODUCING STRAIN AND OPTIMIZATION OF ITS CULTURAL CONDITIONS

从呼和浩特市污水处理厂筛选分离了1株高效絮凝剂产生菌YS2,通过培养条件优化试验确定了该菌株产絮凝剂的最佳培养条件:碳源为蔗糖、氮源为脲、N/C为2.5∶1、初始pH值为6.0、培养温度为30℃。絮凝试验表明:该菌株产生的生物絮凝剂对高岭土悬浊液有良好的絮凝效果,絮凝率达到95%。絮凝活性分布试验表明其絮凝活性全部存在于离心沉降物中,而上清液没有絮凝活性。16S rDNA测序鉴定其为克雷伯氏菌G。

A bacterial strain was screened out from a sewage treatment plant in Hohhot.The optimal cultivation conditions showed that the carbon source was sucrose,the nitrogen source was carbamide,low C/N ratio(C/N=2.5) was beneficial to microbial flocculant production,the desirable cultivation time was 84 hours,cultural temperature was 30℃,the initial pH value was 6.0,60mL culture medium in 150mL total volume of triangular flask(in the case of 200r/min).Flocculation tests conducted by the fermenting solution showed that the cultivation solution had a good flocculation effect on kaolin clay suspension,and the flocculation rate reaches 95% in the best condition.The test of distribution of flocculating activity showed that the supernatant of centrifugation did not have any flocculating activity,all the flocculating activity existed in the deposit of centrifugation. It was identified as Klebsiella sp.G by sequencing of 16S rDNA.