Comparative phytochemical profiling of paprika (Capsicum annuum L.) with different fruit shapes and colors

Abstract

We analyzed the phytochemicals and taste components in paprika varieties with different colored and shaped fruit, and evaluated their antioxidant and alpha-glucosidase inhibitory activity. We collected conical type paprika fruit with brown, red, orange, and yellow (CB, CR, CO, and CY) skin/flesh color and compared their compounds with blocky type paprika fruit with red, orange, and yellow (BR, BO, and BY) skin/flesh color. Carotenoids were analyzed using UPLC, and capsaicinoids, capsinoids, tocopherols, free sugars, and organic acids were analyzed using HPLC. Total phenolic and flavonoid contents, antioxidant activity, and alpha-glucosidase inhibitory activity were measured using a spectrophotometer. We detected 11 carotenoids among the paprika types and the main carotenoid in CB was capsanthin (709 +/- 4 mg kg(- 1) DW). The main carotenoid in CR was zeaxanthin (592 +/- 37 mg kg(- 1) DW), whereas the main carotenoid in BR was capsanthin (701 +/- 45 mg kg(- 1) DW). Interestingly, CB retained chlorophylls thoughout ripening. Citric acid, ascorbic acid, and tocopherols were abundant regardless of fruit color and shape. However, capsaicinoids and capsinoids were barely detected. Comparing paprika varieties with the same color, conical type paprika contained more fructose and glucose than blocky type paprika. Among conical type paprika, CB extract showed the highest antioxidant and alpha-glucosidase inhibitory activities. We showed that conical type paprika was superior in terms of its phytochemical profile. Especially, brown colored paprika contained abundant carotenoids and chlorophylls as well as ascorbic acid, organic acid, and free sugars.