短芽孢杆菌RL-2絮凝机理研究

Study on flocculating mechanism of Bacillus brevis(RL-2)

由编号为RL-2的短芽孢杆菌(Bacillus brevis)产生的生物高分子,经研究发现是一种对高岭土悬液有较高絮凝活性的阴离子型絮凝剂。对絮凝剂的热处理及酶处理表明,其活性成分为多糖;经茚三酮试验,Molish反应,薄层色谱及红外光谱分析表明,该絮凝剂为一种阴离子型多糖絮凝剂;ζ电位测定及絮凝剂与高岭土颗粒之间结合键的检测表明,絮凝剂与高岭土颗粒间的结合力为氢键,絮凝过程基于“桥联”机理;絮凝剂和高岭土在絮凝剂的活性部位———多糖中的羟基或羧基以氢键相结合,经架桥作用絮凝沉淀。

The biopolymer produced by strain RL-2 was found to be an effective anionic flocculant for Kaolin suspensions. The bioflocculant is treated by heat and enzyme, which indicates that the active ingredient of biofocculant is polysaccharide. RL-2 is mainly composed of anionic polysaccharide, which is determined by Ninhydrin reaction, Molish reaction, TLC and infrared spectrum. From the acting force and zeta-potential measurements, it was concluded that the acting force between bioflocculant and Kaolin suspension is hydrogen bond, the flocculation process is based on the bridging mechanism, the combination of Kaolin suspension with RL-2 by hydrogen bond at the active position of polysaccharide.