Determination of the antioxidant activity of capsaicinoids and polyphenols extracted from wild chili pepper

Abstract

Wild chilis are considered a plant-genetic resource native to Mexico; however, the lack of studies on their phytochemical composition limits their sustainable commercial use. This study aimed to evaluate the concentration of capsaicinoids and polyphenols in three varieties of wild chilis from Tezonapa in the high mountains of Veracruz, Mexico, and their correlation with their antioxidant capacity. Determining antioxidant activity and quantifying total polyphenols were performed using spectrophotometric methods, while capsaicinoids were quantified by liquid chromatography. The chili variety factor significantly affected (p≤0.05) antioxidant activity determined by 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) ABTS and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) methods and capsaicinoid concentration. The community factor significantly affected (p≤0.05) the variables mentioned above, in addition to the concentration of total polyphenols. Chiltepin and Mirasol varieties from the community of Manzanares had the highest concentration of total capsaicinoids (246.58 ± 14.93 and 256.75 ± 7.15 mg/100 g). In the case of Tabaquero, those from the community of Cerro Azul presented the highest concentration of capsaicinoids (345.93 ± 14.25 mg/100 g). The three Cerro Azul chili varieties had the highest total polyphenols concentration. The total polyphenols concentration was positively correlated with the antioxidant activity of wild chilis, indicating that these are the main compounds responsible for the antioxidant characteristics in these chili varieties. The knowledge generated in this research will contribute to the conservation of these chili species and benefit the communities of Tezonapa by exploiting these fruits for the agro-food sectors focused on functional foods.