Production of exopolysaccharide by Pseudomonas sp ATCG 31461 (Pseudomonas elodea) using whey as fermentation substrate

An improved strain of Pseudomonas sp. ATCC 31461 (Pseudomonas elodea), capable of producing broth viscosities of 11000 and 4700 mPa s (cP) when grown in enriched whey permeate and enriched sweet whey broths respectively, was isolated. The isolation was by serial transfers of the parent on lactose-rich and sweet whey broths. Maximum viscosities and biopolymer production were observed in 25% (v/v) whey concentration. In whey concentrations of 50% (v/v) or greater, residual glucose was detected in the broth and biopolymer production was low. This strain is capable of totally utilising the lactose in up to 50% (v/v) whey in 64 h. Enzyme activities suggest that the transport of lactose in P. elodea is by the permease system as opposed to the phosphotransferase system. The location of beta-galactosidase is mainly intracellular. The improved strain is able to utilise lactose better than the parent and produce 1.6 times more intracellular beta-galactosidase activity compared to the parent.