Ferric reducing antioxidant power and free radical scavenging activity of Moringa oleifera: Relevance in oxidative stress

Abstract

Moringa oleifera of family Moringaceae, commonly known as Horseradish-tree or the Ben-oil tree is an exceptionally nutritious vegetable tree with a variety of medicinal uses, distributed in tropical and subtropical regions of the world. The tree's bark, roots, fruit (pod), flowers, leaves, seeds and gum are used as an antiseptic, anticancer, anti-inflammatory, hepatoprotective and in treating rheumatism, venomous bites and other conditions. The immature green pods, called ‘drumsticks’ are probably the most valued and widely used part of the tree for water purification (e.g. desalination of ocean salt water). The leaves are highly nutritious, being a significant source of beta-carotene, vitamin C, protein, iron and potassium used in soups and sauces. The present study focuses on concentration-dependent ferric reducing antioxidant power (FRAP), free radical scavenging (DPPH), total phenolics (TP), total antioxidant capacity (TAC) and reducing power (RP) of moringa leaf and fruit (pod) extract compared with standard antioxidant. A strong positive co-relation was observed between FRAP, DPPH, TP and RP activity. Comparatively, the antioxidant potential of fruit extract was more pronounced than the leaf extract and ethanolic extract showed better activity than aqueous. On the basis of our observations, we hypothesize that moringa fruit (pod) and leaves can be a potential source of natural antioxidants due to their marked antioxidant activity.