Characterization and flocculation properties of a carbohydrate bioflocculant from a newly isolated Bacillus velezensis 40B
Zaki, S.A.; Elkady, M.F.; Farag, S.; Abd-El-Haleem, D.
Journal of Environmental Biology 34(1): 51-58
2013
ISSN/ISBN: 0254-8704 PMID: 24006807 Document Number: 670792
In this study, a bioflocculant with a high flocculation activity (> 98%) produced by strain 40B, which was isolated from a brackish water was investigated By 16S rDNA sequence analysis, strain 40B was identified as Bacillus velezensis. Chemical analysis of the bioflocculant 40B indicated that it contained 2% protein and 98% carbohydrates. FTIR analysis showed the presence of carboxyl, hydroxyl and amino groups, which were preferred for the flocculation process. The optimal concentration for the flocculation activity was 3.5 mg (-1). This polysaccharide could also flocculate kaolin suspension over a wide range of pH (1-10) and temperature (5-85 degrees C) in the presence of CaCl2. The stability of the bioflocculant 40B under various conditions suggests its possible use in the industries and environmental applications. However, no previous report exists on the isolation and characterization of a bioflocculant from the Bacillus velezensis.