Immobilization, stability and esterification studies of a lipase from a Bacillus sp.

In the present paper a comparative account of the immobilization of a Bacillus lipase on different solid supports with different surface properties and their thermostability is presented. Immobilization enhanced the thermostability of lipase. At higher temperatures, lipase immobilized and cross-linked on a hydrophobic surface showed the maximum thermostability. The optimum temperature for immobilized lipase was 9 °C higher than for the free enzyme, while the pH optima were the same. The half-life of soluble lipase at 50 °C was calculated to be 4.5 h, while immobilized lipase did not lose any activity even after 8 h. The temperature stability (for 1 h) of immobilized enzyme was enhanced from 50 to 60 °C in comparison with non-immobilized enzyme. Applications of immobilized lipase for esterification are also presented.