Prooxidant Activities of Chlorophylls and Pheophytins on the Photooxidation of Edible Oils

Abstract
The effect of chlorophyll (Chl) and pheophytin (Phy) on the photooxidation of triglycerides was examined. Prooxidant behavior similar to that noted in previously reported experiments using methyl linoleate as a substrate was observed. The prooxidant activity of Phy was found to be higher than that of Chl. Moreover, Chl b accelerated photooxidation to a greater degree than did Chl a, and Phy b was more active than Phy a. From the compositional variation of Chl and Phy during photooxidation, it was found that Phy was stable during oxidation of oils. These facts suggest that the Phy content must be noted when considering the oxidative stability of edible oils.