Abstract A bacterial strain whose flocculating rate could reach 836% was isolated from Bohai seawater samples. The strain was identified as Bacillus amyloliquefaciens by 16S rDNA definition and Biolog test and was nominated as Bacillus amyloliquefaciens dhs-28 ultimately. Ultrasonication test confirmed that its flocculating activity was in fermentation supernatant. Incubating in LB liquid culture at 37 ℃, 180 r/min for 72 h, the strain had the highest flocculating activity.Flocculating active substances were obtained by ammonium sulfate precipitation and dialysis and its flocculating activity was sensitive to pH. It could only maintain flocculating activity while pH varied from 6 to 11, but in a wide temperature range from 0 ℃ to 100 ℃. Saccharide, protein, lipid, nucleic acids qualitative tests showed the flocculating active substances were mainly composed of proteins, as well as a few saccharides. UV scan results suggested the composition of its flocculating active substances was complicated.
HAO Jian-An, YANG , ZHANG Xiu-Zhi, WANG Jing, ZHANG Yu-Shan.Flocculating Activity of Marine Bacillus Amyloliquefaciens dhs-28[J] Chemcial Industry and Engineering, 2011,V28(1): 7-12
2011, Vol. 28 
