The efficacy of walnut (Juglans Regia L.) by-product extract as a free radical scavenger

Abstract

Walnut leaves and green husk are agro-forest wastes generated in the walnut (Juglans regia L.) harvest that could be valued as a source of natural compounds with antioxidant properties. The free radical scavenging activity of studied extracts of walnut leaves and green husk was evaluated by employing antioxidant assay system. Phenolic compounds are the major contributors to the biological properties like antioxidant activities of walnut leaves and green husk. The total phenols content of the extracts was determined using the Folin-Ciocalteu method to assess their contribution to the antioxidant activity. Extract antioxidant activity as well as the kinetics of inhibition of free radicals were evaluated in terms of radical scavenging ability using the stable 2,2 diphenyl-1-picrylhydrazyl radical (DPPH• ). The results of the present study suggest that walnut leaves and green husk extracts, a byproduct of walnut processing industry, can be used as an economical source of natural antioxidants for food, cosmetic and pharmaceutical industries.