COMPOSITION AND STRUCTURE OF BIOFLOCCULANT BP25
絮凝剂BP25的化学组成及结构研究

A strain of Bacillus megaterium screened from activated sludge could produce exocellular flocculant. The flocculant was purified through ethanol precipitation and Sephadex S-500 column chromatography. The purified flocculant BP25 was assayed by Bradford reaction, agarose gel electrophoresis and Sulfate-phenol method. The results showed that BP25 was a kind of polysaccharide which contains 36.97% O, 6.28% H, 47.00% C, 0% No NMR assay showed BP-25 contains no uronic acid. Gas-chromatography assay combined with thin-layer chromatography of acid hydralate revealed that BP25 contains Glucose and Mannose with the mole ratio of 4:1. Methylation analysis revealed the polysaccharide contains alpha-1, 6 glycosidicbond and alpha-1, 3 glycosidicbond. The main chains are comprised of Glucose and all the Mannose are in the side chains. Possible repeating unit structure was deduced.