Bioactive Compounds And Antioxidant Capacities Of Different Fruit

Effect of different edible tissues and flesh colour on variation of contents of bioactive compounds and total antioxidant capacities (TAC) were investigated in the present study.Different edible tissues of citrus fruit, i.e. juice sacs (JS), segment membrane (SM), and segment (Seg) of four species were examined for contents of bioactive compounds and TAC by ferric reducing antioxidant power (FRAP) assay. Two flavanones (i.e. naringin and hesperidin) were identified by HPLC, where hesperidin accounted for 18.5-38.5% of the total phenolics in the species of C. unshiu, C. reticulata, and C. sinensis, while naringin was only found in C. changshanensis and it accounted for 53.7% of the total phenolics in SM of this species. In SM of all selected species, the contents of phenolic compounds and TAC were significantly higher than those in JS and Seg. Highest total phenolics, flavonoids, naringin, and TAC were found in SM of C. changshanensis, while highest carotenoids content was found in JS of C. reticulata. The contribution of vitamin C to TAC ranged from 26.9% to 45.9% in JS and Seg of all selected species. In SM, however, high contribution from hesperidin was observed in C. unshiu (54.0%), C. sinensis (46.7%), and C. reticulata (30.0%). Our results indicated that SM of citrus fruit were high in contents of bioactive compounds and TAC, it is thus recommended to consume citrus fruit with all edible tissues rather than juice or JS alone.Significantly higher levels of anthocyanins (75.9 mg/100 g FW), and phenolics (325.5 mg/100 g FW) were found in dark red-fleshed cultivar of Chinese bayberry, whereas significantly higher total carotenoid content (1955.1μg/100 g FW) was found in orange-fleshed loquat cultivar. Chlorophyll pigments were only detected in kiwifruit and significantly higher vitamin C content (68.4 mg/100 g FW) was observed in strawberry. The TAC (hydrophilic and lipophilic) was highest (31.1 μmol trolox equivalents (TE)/g FW) in dark red-fleshed cultivar of Chinese bayberry and lowest (10.3 μmol TE/g FW) in white-fleshed peach. The HAC was significantly correlated with the contents of anthocyanin (R~2 = 0.97), and phenolic (R~2 = 0.84), while the LAC was only correlated with the carotenoid contents (R~2 = 0.92). The results indicate that either dark red-fleshed fruit species with high anthocyanin contents or orange-fleshed fruit species with high carotenoid contents are good sources of natural antioxidants.