Varietal differences in phenolic, flavonoid and capsaicinoid contents in pepper fruits (Capsicum annuum L.)

Immature and ripe fruits of Japanese hot and sweet peppers were analyzed for total phenolic, flavonoid and capsaicinoid contents. The results showing varietal differences are summarized as follows. The amount of phenolic compounds was higher in hot and ripe pepper fruits than in sweet and immature pepper fruits. There was no difference in quercetin content between hot and sweet peppers during fruit growing. The contents were rather high in 'Hirosaki Zairai', 'Tochigi Santaka' and 'Yatsufusa' hot peppers and in 'Green 300' sweet peppers; the quercetin content of 'California Wonder' and 'Wonder Bell' was markedly low. In all varieties examined, the luteolin content was higher than that of quercetin content, more in hot peppers than in sweet peppers, except in 'Sapporo Ohnaga'. Luteolin content in immature fruits was higher than that in ripe fruits; a reverse relationship occurred in 'Wonder Bell'. Capsaicinoids, that were only detected in hot peppers was highest in immature 'Yatsufusa' and ripe 'Kagawa Hontaka' fruits. Our data reveal that the total phenolics content is a good indicator of the anti-oxidant activity of pepper fruits, and that the anti-oxidant levels in sweet peppers, especially in the ripe fruits of 'Fushimi Amanaga' and 'Wonder Bell' are higher than they are in hot peppers.