Abstract

ESSENTIAL OIL FROM THE FRESH GREEN STALK OF ALLIUM CEPA L. AND THEIR DPPH ASSAY

Zafar Iqbal, Faiza Farman, Lubna Liaqat, Amna Ashraf, Anam Touseef, Anam Asghar

Abstract

Fresh green stalk of the allium cepa were collected from the local field area near Lahore district. These bulbs were cut into small pieces and dried under shade. Essential oil extraction was carried out through hydro-distillation using Linkersson apparatus, followed by extraction with petroleum ether and drying with sodium sulfate anhydrous. GCMS studies were performed to determine the components of the essential oil. Eleven components were identified and the major components were 1-allyl-3-methyl trisulfide (17.69%), 1-methyl-2- (prop-1-enyl) disulfide (15.90%), 1-methyl-3-(prop-1-enyl) trisulfide (15.64%) and 1-methyl-3-propyl trisulfide (12.24%). 2,2-Diphenyl picrylhydrazyl radicalwas (DPPH) was used for the determination of antioxidant activity of the essential oil from the stalk of allium cepa. Maximum antioxidant activity (36.55%) was observed at concentration 100 mg/ml while at the same concentration ascorbic acid gave 99.67%. Antioxidants prevent free radical induced tissue damage by preventing the formation of radicals, scavenging them, or by promoting their decomposition. Sulfur containing compounds are responsible for its antioxidant activity.

Keywords: Antioxidant, Fresh stalk, Alium Cepa L, Hydro-distilllation, Essential oil.