Variations in Biochemical Compounds of Fresh Leaves of Castanea sativa in Relation to Elevation and Stand Age

Abstract

This study investigated the effects of elevation and stand age on the photosynthetic pigments and antioxidant enzymes activities of Castanea sativa leaves. Leaves of C. sativa were collected at 470 m above sea level in stands ranging in age from 15- to 85-year-old and were compared for 13- to 65-year-old with leaves collected at 810 m. Chlorophyll pigments as chlorophyll a (Chl a), chlorophyll b (Chl b) and carotenoids, antioxidant enzymes activities (ascorbate peroxidase, superoxide dismutase, catalase), on-enzymatic compounds (total soluble protein levels, proline), flavonoid, and the oxidative level (hydrogen peroxide (H2O2), lipid peroxidation (MDA-malondialdehyde)) of fresh leaves were analyzed using a UV–visible spectrophotometer. Significant differences in the biochemical compounds of Castanea sativa leaves were found between elevation and stand age. In general, photosynthetic pigments (except for the ratio of chlorophyll a:chlorophyll b), proline, and soluble protein levels, as well as ascorbate peroxidase and superoxide dismutase, had better results at higher elevations than at lower elevations, whereas flavonoids, malondialdehyde, and hydrogen peroxide concentrations, as well as catalase activity, were lower at higher elevations. Results have shown that total chlorophylls, chlorophyll b, proline, at both elevations and catalase enzymes activities at only 810 m were decreased with increasing in stand age whereas chlorophyll a : chlorophyll b at both elevations and total carotenoids at only 810 m were increased with increasing. However, other chemical compounds (chlorophyll a, superoxide dismutase, hydrogen peroxide, lipid peroxidation levels) did not show a significant trend with the stand age. This study has provided valuable insight into the variation in the biochemical compounds of C. sativa leaves in relation to the elevation and stand age, and the results of this study can contribute to the determination of ideal site factors for the growth and development of chestnut trees.