Effect of Evernic Acid on Structure of Spinach Chloroplasts

Abstract

Detached leaves of Spinacia olerácea were incubated with evernic acid, the main phenolic substance presen! in Evernia prunastri thalli. This lichen substance produced a decrease in the amount of total chlorophyll and chlorophyll a in treated spinach leaves. Chloroplast structure suffered a decrease in several parameters, i.e. chloroplast área, number of grana, granal width, number of thylakoids per granum and starch contení. The submicroscopic structure of the chloroplast membranes revealed smaller particle diameters in several of the fracture faces in the evernic acid treated samples and even a decrease in the density of partióles in the EFS fracture face. The alterations observed may be related to changes in photosynthetic activity, probably by modification of both photosystem I and photosystem II activities.