Kinetics and thermodynamics of biocatalytic glycerolysis of triacylglycerols enriched with omega-3 polyunsaturated fatty acids

Abstract

The enrichment of fats with omega-3 polyunsaturated acids increases the nutritive value of fats and makes them more health promoting by boosting the immune system and reducing blood coagulability, the level of neutral lipids and the risk of coronary heart disease and atherosclerosis. That is why it is important to develop scientific basis of the synthesis of these lipid systems. There have been created the mathematical model of kinetics of enzymatic glycerolysis of triacylglycerols enriched with omega-3 polyunsaturated fatty acids, enabling quantitative and qualitative assessment of the reaction composition. For the mathematical modeling of the process, a system of nonlinear differential equations has been created which describes the change in the content of the resulting substrates and reaction products through time. To determine acylglycerol composition of the reaction systems, the high temperature gas-liquid chromatography method was used. The simulation was performed using Mathcad 15 environment via the identification of the parameters of the model by means of a random multivariable search algorithm being called a method of complexes, in the course of which the errors between experimental and model data were minimized. The Runge–Kutta method with a variable step of the fourth order of accuracy was used as a numerical procedure for differential equations modelling. As a result of the calculations, the numerical values of the constants of direct and reverse reactions rates and the corresponding equilibrium constants were determined. Based on the received constants of homogeneous substrates mixtures the values of thermodynamic parameters and activation energies of the studied process have been calculated. The conclusions have been drawn about the contribution of each reaction, occurring during biocatalytic glycerolysis of triacylglycerols, to the process under consideration.