Methanolic Extracts of Grapefruit (Citrus paradesi) Peel, Pulp and Seed and their Antioxidant Activity

Abstract

Fresh grapefruits (Citrus paradesi) were collected from the vegetable market of Lahore Division, Punjab Pakistan. Their peel, pulp, and seed were subjected to drying and grinding which was followed by extraction with methanol. These methanolic extracts were further investigated to check their antioxidant activities by using 2,2-diphenyl-1-picryl-hydrazyl (DPPH). The antioxidant activities showed that the grapefruit peel methanolic extract with concentrations of 25µL, 50µL, 75µL, and 100µL has DPPH inhibition 73.6%, 76.4%, 78.8%, and 82.7% respectively. While the grapefruit pulp methanolic extract having concentrations 25µL, 50µL, 75µL, and 100µL has DPPH inhibition 60.3%, 67.3%, 73.6%, and 78.9% respectively and the grapefruit seed methanolic extract with concentrations 25µL, 50µL, 75µL, and 100µL has DPPH inhibition59.1%, 65.7%, 71.5%, and 75.9% respectively. The results of these extracts were concentration-dependent.