Antioxidant activities, polyphenol, flavonoid, and amino acid contents in peanut shell

Abstract

Peanut shell; a byproduct of an important leguminous crop, peanut; is a potential source of different functional compounds. Antioxidant activities, secondary metabolites and amino acid contents in peanut shells of six Korean cultivars were studied in the present study. Peanut shells showed remarkable antioxidant potentials with high amounts of total polyphenol (428.1–739.8 µg gallic acid equivalents/g), flavonoid (142.6–568.0 µg quercetin equivalents/g), and amino acid (5.76–34.56 mg/g) contents. 2, 2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide dismutase (SOD)-like activity, and reducing power potential of the peanut shells were considerable. The results suggest that the shells of Korean peanut cultivars could be a potential source of natural antioxidants and functional compounds for various industrial uses including cosmetics.