Variation in phenolic compounds, ascorbic acid and antioxidant activity of five coloured bell pepper (Capsicum annum) fruits at two different harvest times.

摘要

The interest in the consumption of pepper fruits (Capsicum annuum L.) is, to a large extent, due to its content of bioactive compounds and their importance as dietary antioxidants. In the present study, the effect of harvest time, based on maturity stage, on changes in the phenolic compounds especially, flavonoids such as quercetin and catechin, total phenols, ascorbic acid, antioxidant activity and taste-related compounds such as total soluble solid (TSS) and titritable acidity (TA) in five different coloured bell pepper genotypes, Arian (orange), Marona (purple), Zorro (dark violet), Y-43-09 (red) and Y-43-07 (yellow), grown as hydroponics system was investigated. The results showed that concentration of antioxidant components and taste-related properties varied among the pepper cultivars at both the mature and whole coloured ripened stages. With advanced maturation, total antioxidant activity increased, however some antioxidant components such as ascorbic acid, total phenols decreased. Furthermore, TSS and TA increased with advanced fruits maturation. The concentration of flavonoids such as quercetin and catechin varied greatly among the pepper cultivars at the two maturity stages. Some cultivars exhibited increase in the amount of these compounds and others decrease with maturation. The richest cultivar in quercetin and catechin content was Zorro with dark violet fruits