The mechanism and kinetic model for glycerolysis by 1,3 position specific lipase from Rhizopus arrhizus

Hydrolysis and glycerolysis of l,3-palimitin-2-olein (POP) was studied and mechanism of glycerolysis was discussed. The results showed that the glycerolysis is a complicated process including hydrolysis, esterification and isomerization of monoglycerides (MG) and diacylglycerols (DG). At first 5 h of glycerolysis, hydrolysis dominates the process and then esterification and isomerization will take place. A new mechanism and kinetic model based on hydrolysis, esterification and isomerization were established to correct all reactions in glycerolysis. The average relative error between experimental data and simulated results is 8.37%. The kinetic model can be used to predicate the results of glycerolysis at different molar ratios of POP to glycerol. The relative errors between the results predicted and experimental data are lower that 10%, which means that the kinetic model can be used to describe for glycerolysis of triglycerides.