Enzymatic Oil Hydrolysis In Solvent-free Medium And Micro-emulsion Medium

The main contents of this artical are as follows:1.Enzymatic hydrolysis of safflower oil catalyzed by LIPASE LVK and lipase AY 30G in a solvent-free and a water-in-oil microemulsions of sodium bis-(2-ethylhexyl) sulfosuceinate(AOT) /isooctane/phosphate buffer solution have been investigated by using safflower oil as the substrat. The effect of the ratio of oil and water,enzyme concentration,reaction temperature,pH,the buffer solution,the Activator,the solvent,the surfactant and reaction time on hydrolysis ratio were studied.and the optimized condition of this condition were fixed.2.The kinetics of the enzymatic safflower oil hydrolysis catalyzed by a lipase from aspergillus niger was investigated in the solvent-free medium and the AOT/Isooctane/phosphate buffer micro-emulsion medium. The activation energy of the reaction was calculated from the Arrhenius plot and the values were 32205J·mol^-1 and 7391J·mol -1in solvent-free medium and micro-emulsion medium respectively. It was found that the denaturation of the lipase in micro-emulsion proceeded faster than in solvent-free medium. The apparent Michaelis constant Km was 0.135 mol·L^-1 in solvent-free medium, however, 0.101 mol·L^-1 in micro-emulsion medium. The experiment indicated that the inhibition of Alcohol towards lipase is a reversible competitive inhibition both in the solvent-free medium and the micro-emulsion medium .In addition , the substrate inhibition appeared in the two systems when the substrate concentration exceeded 0.819 mol·L^-1.3.The hydrolyzate was separated and inspected,the selectivity of Lipase LVK,Lipase AY 30G and Lipase F-AP15 on ester position and the fatty acid were studied.Lipase LVK and Lipase AY 30G don't show any selectivity and Lipase F-AP15 show some ester position selectivity in this reactivities.