Lipase-catalyzed Production Of Monolaurin And Decyl Acetate

Lipases were widely used among the fields of food, forage, cosmetics, and medicine. Lipases act effectively under mild conditions and have several advantages such as lower consumption of energy, little pollution, and higher selectivity and so on. Lipase-catalyzed reactions have already been attracted much attention. This paper mainly studied reactions catalyzed by Candida antarctic lipase B (CALB).Firstly, the ability of lipase to catalyze the direct esterification of lauric acid and glycerol with tert-butanol as a reaction medium was investigated. Results showed tert-butanol amount and substrate molar ratio had great effect on the selectivity to monolaurin (ML). And reaction temperature had less effect on the selectivity. Optimum synthesis conditions were:reaction time1.5h, temperature40℃, enzyme load12%, substrate molar ratio of glycerol to fatty acid3:1and tert-butanol/glycerol ratio (w/w)1:1with up to70%monoacyglycrol (MAG) content in the reaction. Tert-butanol was favorable solvent for the synthesis of MAG.Secondly, the vinyl acetate and decyl alcohol were catalyzed by lipase in continuous operation. The paper was focused on optimizing the conditions of continuous reaction such as the temperature, the ratio of the vinyl acetate and decyl alcohol, and fluid speed. And the40℃would be good for this reaction. The optimal ratio of the ester and alcohol was1:1(mol/mol). The most suitable fluid speed was1.98mL/min (reaction time was1.3min). And the conversion could be up to96%.Finally, it was the first time to use vapor permeation in the production of MAG through designed membrane reactor of vapor permeation. It was much higher with the membrane reactor than conventional reactor in terms of MAG conversion at temperature70℃, enzyme load10%, tert-butanol/glycerol ratio (w/w)1:1. The yield of MAG was up to92%in the designed membrane reactor. The effects of adding n-hexane in ter-butanol was investigated. And the conversion yield of MAG was increased by7%due to the addition of hexane in tert-butanol.