VARIATION IN CHEMICAL CONSTITUENTS AND ANTIOXIDANT ACTIVITY IN YELLOW HIMALAYAN (RUBUS ELLIPTICUS SMITH) AND HILL RASPBERRY (RUBUS NIVEUS THUNB.)

Phytochemicals and antioxidant activity in the fruits of Rubus ellipticus and Rubus niveus were studied. A significant variation (P < 0.05) in total phenolics, flavonoids, monomeric anthocyanins, ascorbic acid and beta-carotene content among genotypes of R. ellipticus was observed. Total phenolics ranged from 2.56 to 3.28 mg gallic acid equivalent (GAE)/gram (g) fresh weight (fw) for R. ellipticus and 3.21 mg GAE/g fw for R. niveus. Gallic acid, catechin, chlorogenic acid and caffeic acid were the major phenolic compounds identified by reversed-phase high-performance liquid chromatography. Antioxidant activity measured by three in vitro assays (i.e., ABTS and DPPH radical scavenging activity and ferric-reducing antioxidant power) demonstrated the utility of both the species as a source of natural antioxidants. Furthermore, the results of this study may provide baseline data for future breeding programs for variety improvement.