Antioxidant and antimicrobial activity of legume hulls

Antioxidant activity of aqueous hull extracts of commonly consumed legumes in India namely Vigna radiata (mung bean), Cicer arietinum (Bengal gram) and Cajanus cajan (pigeon pea) was studied by several in vitro assays. The extracts showed high phenolic content and excellent DPPH scavenging activity (75-85%) at very low concentration. The IC50 values for superoxide radical scavenging activity was also low (85-150 mu g/ml). The antioxidant activity coefficient as determined by beta-carotene bleaching assay was very high (828-1086). The hull extracts also exhibited high reducing power indicating good antioxidant potential. Of the extracts studied pigeon pea hull extract had the highest antioxidant activity. It also exhibited good antibacterial activity against Bacillus cereus. This study indicated that legume hulls have good antioxidant potential comparable to the synthetic antioxidant butylated hydroxy toluene and could therefore have application in food, cosmetic and pharmaceutical industry. (C) 2011 Elsevier Ltd. All rights reserved.