Chemical Composition, Antioxidant, Lipid Peroxidation Inhibition and Free Radical Scavenging Activities of Microwave Extracted Essential Oil from Allium sativum

Abstract

Various chronicle diseases are associated with oxidative stress caused by free radicalsand reactive oxygen species in the living cell system. In the present study, the chemical composition and antioxidant capacity of Allium sativumessential oil (ASEO) were investigated using different scavenging models including 1,1-diphenyl-2-picryl hydrazyl (DPPH), nitric oxide, superoxide, and hydroxyl radicals. Also the ASEO was evaluated for its lipid peroxidation inhibition efficacy, reducing power ability and total phenolic contents. The ASEO was obtained by the hydrodistillation of the dried rhizomes of A. sativum using a microwave-assisted extraction technique. Gas chromatography-mass spectrometry analysis of the ASEO resulted in the determination of 17 different compounds, representing 92.46 % of the total oil. The major components in the ASEO were phenolics, saturated fatty acids, sugar alcohols, esters, hydrazine, quinoline and isoquinoline derivatives along with some other essential phytochemicals. The ASEO showed the antioxidant capacity as the inhibition of DPPH, nitric oxide, superoxide, and hydroxyl radicals by 72.06 %, 79.96 %, 72.66 %, and 71.21 %, respectively. Moreover, the ASEO displayed concentration-dependent reducing power ability and remarkable ferric ion-induced lipid peroxidation inhibitory effect in bovine brain extract. In addition, the ASEO yielded 5.75±0.21 mg/ g gallic acid equivalent phenolic content. The findings of the present study confirm the efficacy of A. sativumas a potential source of natural antioxidant.