Study On Bioflocculant Excreted By A Streptococcus Sp.

Bioflocculant is an important sort of the macromolecular flocculants. It has such advantages: no toxicity, no pollution. Bioflocculant produced by microorganism can be easy to achieve industrialization through biology engineering and biodecomposed.The microorganism that can produce bioflocculant was screened by conventional method from the soil. One streptococcus strain possess capsule was separated completely. The result indicates: the method observing the community shapes was simple and convenient for screening flocculants producing microorganisms.The studies were focused on the optimum culture medium, culture conditions and apply conditions. The investigation of flocculating the alkaline kaolin suspensions suggests that metal ions can affect the flocculate rate distinctly. A likely model was put forward based on experiment phenomena.Ethanol and Sevag precipitated the bioflocculant that was purified to homogeneity through Sephadex-DEAE A-25 and Sepharose 4B gel chromatogram columns. The results suggested the effective component in bioflocculant was polysaccharide characterized by TLC GC UV IR and elemental analysis. The biopolymer contained sugar (73%) and uronic acid (20.6%), elemental analysis suggested little amdio and peptide might exist. The molecular weight measured by HPLC was 1.0 X 105.63Da.The flocculation effect, SS was removed distinctly; of bioflocculant on the treatment of lapis waste water was observed. Turbidity analysis indicated additional Ca2+ and agitation would improve the water quality. Turbidity Removal efficiency is up to 83%.