CHANGES OF LIPOXYGENASE AND FATTY-ACID HYDROPEROXIDE LYASE ACTIVITIESIN BELL PEPPER FRUITS DURING MATURATION

Developmental changes in fatty acid hydroperoxide lyase (HPO lyase) an d lipoxygenase (LOX) during the maturation of bell pepper fruits (Caps icum annuum L. cv, Kyonami) were examined by means of activity measure ments, immunological detection of both the enzymes, and analysis of th e volatile compounds formed upon homogenization of the fruits. Both th e enzyme activities decreased with maturation, and immunological studi es showed that the amounts of the enzymes concomitantly decreased. The amounts of sis-carbon aldehydes and alcohols formed from bell pepper fruits upon homogenization also decreased during maturation, and with the fully ripened red fruits, these volatile compounds were hardly det ectable. These results suggest that the major factor contributing to t he changes in the composition of volatile compounds during the maturat ion of bell pepper fruits was changes in the amounts of HPO lyase and LOX.