Characterization and Flocculating Properties of a Biopolymer Produced by Halomonas sp. Okoh

The flocculating efficiency and physiochemical properties of purified bioflocculant produced by Halomonas sp. Okoh were investigated. Approximately 1.213 g/L of bioflocculant was recovered after fermentation under predetermined ambient conditions. Jar test experimentation revealed optimum bioflocculant concentration as 0.2 mg/mL with flocculation activity of 66.1%. The thermostable bioflocculant retained high flocculation activity after heat treatment at 100 °C for 30 minutes; flocculation activity of 74% was achieved. Chemical analysis showed that the bioflocculant was composed of sugar (26.5%), protein (2.64%), and uronic acid (13.3%). The Fourier infrared spectroscopy spectrum of the purified bioflocculant revealed the presence of hydroxyl and carboxylic functional groups. Thermogravimetric analyses showed a varied decomposition step, thus, an indication of varied composition. Scanning electron micrograph revealed the amorphous structure of the bioflocculant. These results suggest potential applicability of the bioflocculant produced by Halomonas sp. Okoh industrially.