Bioactive components and antioxidant capacity of Chinese bayberry (Myrica rubra Sieb. and Zucc.) fruit in relation to fruit maturity and postharvest storage

Total phenolics, flavonoids, anthocyanins, cyanidin-3-O-glucoside (Cy-3-glu) and antioxidant capacity of Chinese bayberry fruit (Myrica rubra Sieb. and Zucc.) differed among the four cultivars Baizhong (white), Fenhong (pink), Wuzhong (red) and Biqi (dark red). Antioxidant capacity determined by both the ferric reducing antioxidant power (FRAP) assay and 2,2-diphenyl-2-picrylhydrazyl (DPPH.) radical scavenging capacity was significantly correlated with the antioxidant components in the fruit, and directly related to fruit color. Cy-3-glu accounted for at least 82, 38, and 12% of the total antioxidant capacity in Biqi, Wuzhong and Fenhong fruits, respectively. No detectable Cy-3-glu was found in Baizhong fruit. Greater fruit maturity was associated with higher levels of all the bioactive components and antioxidant capacity. Significant increases were also found during postharvest storage of Biqi fruit held at either 20 degrees C for 2 days or 0 degrees C for 5 days. However, these levels decreased during a 2-day shelf-life at 20 degrees C after 5 days at 0 degrees C. These results show that storage and shelf-life conditions are important if health-based bioactive components of bayberry fruit are to be maintained after harvest.