Stability in organic solvents of immobilized lipase on pectin microspheres

L. COSTAS; V.E. BOSIO; A. PANDEY; GR CASTRO

Ciudad de Trivandrum

Congreso; International Conference on New Horizons in Biotechnology; 2007

Hydrolases, like lipases are gaining more attention in the biotechnology field because of many useful synthetic activities. However, most of the enzymes are not able to resist at high concentration of organic solvents, and/or extreme pH and temperatures. In addition, enzyme recycling is desirable in any biotechnological process. A wild-type bacterium characterized as Brevibacillus agri 52 able to synthesize an extracellular lipase but without protease activity was cultivated in batch culture for 24 hours. Maximal production of lipase was found at the beginning of stationary growth phase (about 17-20 hs.). Lipase activity was not altered in presence of 50% etilenglicol and glycerol, but was fully inhibited in presence of 50% acetone. Enzyme immobilization is a feasible alternative in order to improve biocatalytic activity in organic solvents and enzyme recycling. On the other hand, pectin, a heteropolysaccharide, has the advantages of gelling in presence of divalent cations, is biodegradable, non-toxic, and obtained from higher terrestrial plants. In the present work, pectin microspheres loaded with B. agri lipase were obtained in presence of calcium ions. The immobilization procedure decrease the enzyme activity in about 22 %, however lipase activity was preserved in acetone, glycerol and also etilenglicol for one hour at 37ºC.