Capsaicinoid content, pungency and antioxidant potential of Himalayan hot pepper

Abstract

Hot pepper (Capsicum annuum L.) is one of the most important vegetable crops grown worldwide due to its culinary values and potential pharmaceutical applications. Capsaicinoids in hot pepper are the secondary metabolites responsible for its pungency. Since capsaicinoid content depends on the environment, betteradapted genotypes with higher capsaicin content are always required. In the present study, we performed a biochemical screening of twenty-two North-Western Himalayan adapted hot pepper breeding lines. We determined their capsaicin content, dihydrocapsaicin content, total phenolic content, pungency, and antioxidant activity. The HPLC analysis quantified 1000 to 4010 µg/g capsaicin and 489 to 1863 µg/g of dihydrocapsaicin, translating to pungency of 16000 to 64160 SHU. The germplasm expressed 28.44% to 78.61% DPPH free radical scavenging activity, 121.29 to 394.294 µM Fe2+/g dry weight (DW) ferric reducing antioxidant power (FRAP) and 4.31 to 8.56 mg/g GAE of total phenolics. Our results identified CITH-HP-91-13 and CITH-HP-92-13 as the breeding lines richest in capsaicinoids and antioxidant activity. The germplasm has been grouped into five clusters based on standardized squared Euclidean distance using Ward’s hierarchical clustering and separation based on PCA biplot. Our study revealed significant differences among breeding lines for tested parameters, which indicate the possibility of exploiting them for quality improvement programme of Kashmiri pepper.