Abstract:

‘Zaofeng’wampee and‘Jixin’wampee cultivars were respectively selected as materials representing for sweet and sour wampees. The components and contents of soluble sugars，organic acids and polyphenolics at young fruit stage，color changing stage and ripening stage were measured；antioxidant activities at three different stages were analyzed by ORAC and CAA assay. Results showed that soluble sugars were continuously accumulated during fruit development in both‘Zaofeng’and‘Jixin’wampee cultivars. At ripening stage，the contents of fructose and glucose in‘Zaofeng’wampee were higher than sucrose，while the sucrose content was higher than fructose and glucose in‘Jixin’wampee. The contents of organic acids in‘Zaofeng’wampee and‘Jixin’wampee varied greatly during fruit development. There was little difference between them at young fruit stage，however，organic acids were almost not detected in ‘Zaofeng’wampee at color changing and ripening stages. While the content of citric acid increased sharply at color changing stage and then decreased at ripening stage in‘Jixin’wampee fruit. The contents of total phenolics and phenolic compounds in‘Zaofeng’and‘Jixin’wampee decreased during fruit development. The content of total phenolic in‘Jixin’wampee was 13.6 times higher than that in‘Zaofeng’wampee at young fruit stage，and was about eight times higher than that in‘Zaofeng’wampee at color changing and mature stages. Six phenolic compounds were detected in wampee fruit，in which rutin was the main component，while syringin was the differential component between‘Zaofeng’and‘Jixin’wampees. The young fruit showed the highest antioxidant activity both in‘Zaofeng’and‘Jixin’wampees as measured by ORAC and CAA methods，and then the antioxidant activity decreased during fruit development. The antioxidant activities of‘Jixin’wampee fruit significantly higher than that of‘Zaofeng’wampee fruit.

Key words: wampee fruit, soluble sugar, organic acid, polyphenolics, antioxidant activity