Effect of the Temperature and Molar Ratio of Water-Oil on the Enzymatic Hydrolysis Kinetics of the Soybean Oil: Experimental and Mathematical Modeling

The objective of this paper was to evaluate the kinetics of the hydrolysis of soybean oil by the action of the Lipozyme^® TL IM enzyme varying the operational conditions of molar ratio water/oil (9:1-60:1) and temperature (40-64 °C). To describe the experimental data, a mathematical model based on the kinetic mechanism of Ping-Pong Bi Bi (PPBB) was proposed, in which the following steps were not considered formation of the complex enzyme/oil substrate, and formation of the acylated enzyme/oil substrate complex. The results of enzymatic hydrolysis of soybean oil indicated a yield in free fatty acids of 76% at the molar ratio of 46:1 and temperature of 52 °C. Furthermore, based on the values of the determination coefficient and root mean square error, the mathematical model based on the kinetic mechanism of PPBB showed good agreement with the experimental data in a relatively wide temperature range. Thus, it can be a useful tool for the optimization and assessment of the mechanisms of enzymatic hydrolysis of vegetable oil.

Keywords:
enzymatic catalysis; soybean oil; Lipozyme^® TL IM; Ping-Pong Bi Bi mechanism