产生物絮凝剂自生固氮菌HY1141的筛选及培养条件优化

Screening of Bioflocculant-producing Azotobacter HY1141 and Optimizing of its Culture Condition

从48株自生固氮菌中筛选出一株高效絮凝剂产生菌HY1141。比较确定其最佳碳、氮源后,再通过正交试验筛选最佳培养基和最佳培养条件。结果表明,该菌株的最佳碳源为蔗糖,最佳氮源为N2。在不加外源氮素的前提下,最佳培养基为蔗糖5g/L,磷酸二氢钾1·5g/L,硫酸镁0·6g/L。最佳培养条件为转速150r/min,培养温度35℃,培养基初始pH7·0、培养时间36h。在此条件下,该菌产生的絮凝剂对高岭土悬液的絮凝率达96·4%。

A high efficient bioflocculant-producing strain HY1141 was screened from the 48 azotobacter bacterial strains. After determination of the optimal carbon and nitrogen source, its optimal medium and culture condition were screened by an orthogonal test. The results showed that the optimal carbon source is sucrose and the optimal nitrogen source is N2. In the absence of exotic nitrogen, the optimal medium consists of sucrose 5 g/L, KH2PO4 1.5 g/L and MgSO4 0.6 g/L. The optimal culture condition includes rotation speed 150 r/min, culture temperature 35 ℃, original medium pH 7.0, culture time 36 h. Under such conditions, the highest flocculating rate of flocculants produced by HY1141 to Gaoling clay suspension is as high as 96.4 %.