Extraction, Estimation and Utilization of Curry Leaf (Murraya koenigii) Stalks as a Potential Source of Antioxidants

Abstract

Background: Processing wastes that are generated at industrial and house hold level are a huge concern. Utilization of these by-products and their bioactive compounds is a blooming industry at present. This study has been designed to unleash the potential of such by-product (stalks) and their possible application. Methods: In order to use plant by-products as a potential source of antioxidants, the methanolic, aqueous methanolic and aqueous extracts of the curry leaf stalks were studied. The nutrient, anti-nutrient, phytochemical content and in-vitro antioxidant activities were assessed for the stalks. The plant extracts were then incorporated in sunflower oil and tested for stability of oil upon repetitive deep frying. Result: Total phenolic content and flavonoids followed the order of aqueous methanolic greater than aqueous greater than methanolic extracts. The phytochemical analysis of the extracts for total flavanols followed the order aqueous greater than aqueous methanolic greater than methanolic. In vitro antioxidant activities of the extracts in DPPH, FRAP, reducing power and CUPRAC assays followed the order aqueous methanolic greater than methanolic greater than aqueous extracts. Therefore, aqueous methanol is a suitable solvent among the three solvents for extracting most active components with higher antioxidant activity from the stalks. Findings from the present study infer that Curry leaf stalks can be a potential source of natural antioxidants and can be used in foods and pharmacological formulas.