ENZYMATIC-SYNTHESIS OF ACETYLATED GLUCOSE FATTY-ACID ESTERS IN ORGANIC-SOLVENT

Two immobilized lipases from Candida antarctica (SP 382) and C. cylindraceae, now rugosa (200I), catalyzed the synthesis of novel acetylated glucose fatty acid esters with glucose pentaacetate (GP) and Trisun 80 (80% oleic) vegetable oil or methyl oleate as substrates in organic solvents. The relative yield was between 6.4-52%, and the incorporation of oleic acid onto the glucose was between 31-100%. In addition, these enzymes were able to catalyze the synthesis of glucose fatty acid esters with free glucose as the sugar substrate. The highest oleic acid incorporation (100%) was obtained in benzene with SP 382 lipase and Trisun 80 as the acyl donor. With methyl oleate as the acyl donor, greater incorporation was obtained in benzene (90.5%) com pared to 75% in isooctane. The 200I lipase was better in benzene/pyridine (2:1 vol/vol) (74%) and chloroform (61%) compared to benzene and isooctane. However, with free glucose and Trisun 80 as substrates, both enzymes gave acceptable levels of oleic acid incorporation (82-100%) in benzene, benzene/pyridine and pyridine. The best conditions for the ester interchange reaction reported are: lipase (10% by weight of substrate); incubation time 48 h; molar ratio of Trisun/GP 1:2; 3 mL solvent and 3% added water. These glucose esters have potential applications as emulsifiers in food, cosmetics and pharmaceutical formulations.