Lipase-catalyzed Reactions at Interfaces of Two-phase Systems and Microemulsions

This work describes the influence of two polar lipids, Sn-1/3 and Sn-2 monopalmitin, on the activity of lipase in biphasic systems and in microemulsions. In previous communications, we have shown that Sn-2 monoglycerides can replace Sn-1,3 regiospecific lipases at the oil–water interface, causing a drastically reduced rate of lipolysis. We here demonstrate that even if the lipase is expelled from the interface, it can catalyze esterification of the Sn-2 monoglyceride with fatty acids in both macroscopic oil–water systems and in microemulsions, leading to formation of di- and triglycerides

Rhizomucor miehei lipase remains highly active at water activity below 0.0001

AbstractThe lipase from Rhizomucor miehei adsorbed on polymer beads retains substantial catalytic activity even after exhaustive drying, and the use of dry box procedures to prevent entry of atmospheric water. Rates of esterification and transesterification (alcoholysis) were measured while stirred in hexane pre-dried to similar low water activity (aw). The rate of dodecyl decanoate synthesis was over 30% of that at the optimum (aw 0.55) after drying with anhydrous CuSO4 or MgO (aw<10−4). Freshly reactivated molecular sieve could cause a further reduction in, but not elimination of, activity