KINETICS OF DECOMPOSITION OF HYDROPEROXIDES FORMED DURING THE OXIDATION OF SOYA PHOSPHATIDYLCHOLINE BY ANALYSIS OF CHEMILUMINESCENCE GENERATED

Chemiluminescence (CL) can be used to measure the extent of oxidation of soya phosphatidylcholine (S-PC) as has been shown previously, utili zing a mixture of the S-PC with medium chain monoacylglycerol. The CL data obtained from such a measurement was examined in this work to est imate the kinetics of decomposition of hydroperoxides that are generat ed by oxidation. CL intensity has been counted in an inert atmosphere at various temperatures and the data analyzed by non-isothermal and is othermal reaction kinetic analysis, primarily based on isoconversion m ethods. The isothermal data has also been analyzed to obtain an estima te of the order of reaction. The apparent activation energy for the hy droperoxide decomposition steps in this system is obtained as 74 and 6 2 kJ/mol; the reaction order changes from 2 to 1 as the reaction proce eds and the hydroperoxides are consumed. Possible mechanisms of hydrop eroxide decomposition have been discussed.