Abstract:

The effects of UV-C treatment at different dosages on postharvest quality, antioxidant activity, phenylpropane
metabolite contents, and related enzymes activities in Chinese bayberry fruit (cv. Dongkui)were investigated. The fruit were
treated with 0, 1.5, 3.0, 4.5 and 6.0 kJ/m2 of UV-C and then stored at 5 ℃ for up to 12 days. The results indicated that UV-C
treatment at 3.0 kJ/m2 had the most significant inhibitory effect on fruit decay. The decreases of fruit firmness and vitamin C
content were retarded and thus fruit quality was maintained. Meanwhile, this UV-C treatment significantly enhanced the
activities of phenyalanine ammonialyase, 4-coumarate-CoA ligase, chalcone isomerase and cinnamate 4-hydroxylase, and
maintained high levels of total phenolics, anthocyanin, carotenoids and flavonoid and high antioxidant activity during the
storage. These results suggest that UV-C treatment has a promising application prospect in quality maintenance of harvested
Chinese bayberry fruit.

Key words: ultraviolet-C, Chinese bayberry, quality, antioxidant activity, phenylpropanoid metabolism