Simultaneous production of exopolysaccharide and lipase from extremophylic Pseudomonas aeruginosa san-ai strain: a novel approach for lipase immobilization and purification

In this study, exopolysaccharide (EPS) produced by an extremophylic strain of Pseudomonas aeruginosa san-ai was used as a support for immobilization of lipase produced together with EPS, using new and simple, single step procedure. The highest EPS production (36.5 mg L−1) was observed in the Luria Bertani (LB) medium supplemented with sunflower oil and Tween 80. The EPS structure was analyzed by FT-IR and 1H NMR, and it was found that EPS from P. aeruginosa is of the alginate type. Lipase, produced by the same strain was entrapped in Ca–EPS beads, formed by dripping a concentrated culture supernatant in CaCl2 solutions. Effects of immobilization conditions on loading efficiency and immobilization yield were investigated, and the potential for reuse of immobilized lipase was monitored. It was shown that the immobilized enzyme could be used for up to three reaction cycles, after which 77% of activity was retained.