产絮凝剂双菌复合发酵体系的研究以及在水处理中的应用

Investigations on producing bioflocculant by double microorganisms and its application on water treatment

从土壤和活性污泥中筛选到三株絮凝剂产生菌,将其进行双菌混合培养的正交试验,构建出了比单一菌所产絮凝剂絮凝活性更高的复合菌群LH,通过16SrRNA序列分析,初步判定二菌分别为Micrococcus sp.和Paenibacill usvelaei菌.对其性质的初步研究发现,复合菌LH所产絮凝剂MBF-LH为胞外代谢产物,其热稳定性好.LH产絮凝剂的最适碳源、最适培养温度、最适pH值和通气量分别为蔗糖、30℃、pH8和120r/min恒温振荡培养.培养基中添加KCl、CaSO4、K2HPO4能明显提高发酵液絮凝率.絮凝剂MBF-LH处理废水时具有用量少、絮凝率高的特点.

Three strains of bacteria which produce flocculating substances were isolated from activated sludge and soil.Every two strains of the bacteria among the 3 strains obtained above were selected to mix ferment by orthogonal experiment.The results showed that the combination of two strains called LH possessed the best flocculating activity.Identified on the base of 16SrRNA gene sequence,the two strains were pertained to Micrococcus sp.and Paenibacillus velaei.Though the preliminary study of the MBF-LH,it had been confirmed that MBF-LH is a kind of extracellular biopolymer and has a good thermostabilization.The best carbon source,optimal cultural temperature,initial pH value and rate of rotary shaker were saccharose,30 ℃,pH 8 and 120 r/min.Addition of KCl,CaSO4 and K2HPO4 to the culture medium could obviously increase the flocculating rate.When applied to the wastewater treatment,MBF-LH had some good properties such as low dosage and high efficiency.