Optimization of cultural conditions for extracellular polymeric substances (EPS) production by burkholderia using response surface methodology

Abstract

Extracellular polymeric substances (EPS) are complex biopolymers secreted by a variety of microorganisms. Except for the basic protecting cells from rigorous environment, EPS also influenced the bioflocculation and settleability of sludge. There were reports about the application of EPS in minimizing harbour siltation. On the basis of this point, a series of experiment were proceeded. Based on single factor experiment, the cultural conditions for EPS production were investigated and optimized by response surface methodology (RSM) at the Box– Behnken design. Optimal EPS yield (6.40 g/L) was obtained at a combination of sucrose 21.0 g/L, NH4Cl 1.1 g/L, MgSO4 0.2 g/L. And the influence of NH4Cl for EPS yield was the most significant, as the rest in order was sucrose and MgSO4. A verification experiment confirmed the reliability of the model.