Changes in phytochemical and antioxidant activity of selected Red pepper (Capsicum annuumL.) cultivars—Chemometric approach

Abstract

In this paper, 18 red pepper samples were grown under different field conditions (without and with irrigation) and analyzed regarding their phytochemical composition and antioxidant activity. The total phenols content (TPC), determined according to the Folin–Ciocalteu method, varied from 485.36 to 601.19 mg/100 g dry matter (DM), while the total flavonoids content (TFC), determined by aluminum chloride colorimetric assay, varied from 301.68 to 493.14 mg/100 g DM. Antioxidant activity was assessed by 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging capacity and ranged from 1.85 to 2.95 mg/ml. Regarding average yield, without irrigation, it was 15.50 t/ha, while with irrigation it was 17.70 t/ha. The antioxidant activity of the samples was predicted by applying multiple linear regression (MLR) based on their chemical composition. The rule for allocating red pepper samples of an unknown group to the correct group of samples (those without irrigation and those with irrigation) was established applying linear discriminant analysis (LDA). Practical applications The 18 red pepper (Capsicum annuum L.) samples were grown under field conditions, without and with irrigation. The antioxidant activity of red pepper was predicted using multiple linear regression (MLR). Applying linear discriminant analysis (LDA) a rule for allocating red pepper samples of an unknown group to the correct group of samples (with or without irrigation) was obtained based on their chemical composition and antioxidant activity.