Abstract: We studied the dynamic changes of polyphenols and their relationship with antioxidant capaci- ty in different organs of Muscat Hamburg by measuring the contents of polyphenols and free radical scavenging activity in different growth periods. The content of total polyphenols, flavonoids and Proanthocyanidins(PAs) in leaf, stem and tendril decreased at first, increased with the development of the grape berry, became the lowest in the fast growth stage of the grape berry, and then increased to a certain degree. The content of poly- phenols was the highest in leaf and the lowest in stem. The trend of polyphenols in skin was the same as in leaf, stem and tendril, and became the lowest in the grape ripening period, while the content of polyphenols in grape pulp was very low and stable during growth periods. The positive correlation of the antioxidant capacities of grapevine organs and polyphenols was found.

Key words: Grapevine, Organ, Total polyphenol, Flavonoid, Proanthocyanidins, Antioxidant capacity