Antioxidant composition and activity of aronia leaves at different stages of maturity

In this study, the leaves of aronia (Aronia melanocarpa) across different stages of maturity were collected and their chlorophyll content, antioxidant content, and activity were analyzed. The leaves of the selected aronia cultivars ('Viking', 'McKenzie', and 'Kingstar K1') were harvested in June (young-stage leaf) and in August (old-stage leaf). The antioxidant content and activity of all three aronia cultivar leaves were significantly higher in the young-stage leaves than in the old-stage leaves. The main polyphenols in aronia leaves were catechol and chlorogenic acid, which tended to decrease as maturation progressed. As a result, the young-stage aronia leaves contained more abundant flavonoids, phenolic compounds, and polyphenols with higher antioxidant activity than those in the old-stage leaves. Overall, our findings indicate that aronia leaves contain potential bioactive compounds that could be used to develop functional food ingredients.