Immobilized lipase-catalyzed ethanolysis of sunflower oil in a solvent-free medium

The ethanolysis of sunflower oil (SFO) with Lipozyme (immobilized 1,3-specific Mucor miehei lipase) in a medium solely composed of substrates was investigated. The effects of oil/ethanol molar ratio, temperature, added water content, and amount of enzyme were analyzed. The optimal values were, respectively, 1:3, 50 degrees C, 0% (vol/vol), and 0.4 g of Lipozyme per 5.7 mmol of SFO. The use of immobilized lipase made the reuse of enzyme feasible, and the enzyme.could be recovered easily from the reaction mixture and recycled to reduce the cost of catalyst. In the last three consecutive runs of enzyme reuse, the final conversion yield of SFO from ethanolysis with added silica gel support was higher than that obtained from ethanolysis under standard conditions. The lipase-catalyzed alcoholytic reaction is potentially useful in the production of alkyl esters of specific interest.