Journal of Pure and Applied MicrobiologyVol. 6 No. 4

Characterization of An Extracellular Bioflocculant Produced by Cobetia sp. OAUIFE Isolated from a Marine Sediment

Ugbenyen Anthony Moses, Mkwetshana Noxolo and Okoh Anthony Ifeanyi*

Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, South Africa.

Received on 28 June 2012 and accepted on 06 August 2012



The characteristics of a bioflocculant produced by Cobetia sp. OAUIFE isolated from sediment samples of Algoa Bay, South Africa was investigated. The acidic extracellular polysaccharide bioflocculant optimally flocculated kaolin suspension at a dose of 0.4 mg/ml, neutral pH of 7, and Ca2+ as a coagulant aid. The bioflocculant is thermostable, with a high residual flocculating activity of 72 % after heating at 100 oC for 30 min. Thermogravimetric property of the bioflocculant revealed only about 50 % loss of initial weight when heated at 500 oC. FTIR analysis of the compound bioflocculant indicated the presence of hydroxyl, carboxyl and methoxyl functional groups. Scanning electron microscopy (SEM) image revealed a crystal-linear spongy-like bioflocculant structure.

Keywords : Cobetia sp., Bioflocculant, Polysaccharide, Thermostable.