KINETICS OF IMMOBILIZED LIPASE-CATALYZED HYDROLYSIS IN SUPERCRITICAL CARBON DIOXIDE

摘要

Arachidonic acid plays important role in neonatal development, addition of it in infant formula has been suggested. It also has a significant effect on prevention and cure for a lot of disease. In order to concentrate it in crude oil effectively, a combined process of immobilized lipase catalysis and extraction of product with supercritical carbon dioxide was applied in our studies. White soil was used as sorbent to overcome the problem of fix. Novozym 435, an immobilized lipase, was chose as catalyst in this reaction. An experiment design was used where enzyme concentration temperature, pressure, water activity, substrate concentration were varied. Furthermore, the kinetics of this reaction was studied. The optimum condition for this reaction is 60mg; 4000PSI, Aw=0.55, substance concentrate is 200g/l,enzyme concentration is 50%w/w. Finally ,the kinetic parameter obtained in this reaction is km =28.974g/l,vmax=0.02679g.