Chemical Composition, Antioxidant Activity of the Essential Oil of Thymus algeriensis Boiss, North Algeria

The leaves of Thymus algeriensis Boiss. collected from middle-North of Algeria (Sidi Aissa, M'sila). Essential oil from the stem bark of Algerian species of Thymus algeriensis Boiss. of the family of Lamiaceae was obtained by hydro-distillation using Clavenger apparatus, possessed an essential oil in 1.3 % (v/w) yield. GC and GC/MS analysis were carried out on the essential oil and was found to contain Seventy-one compounds, representing 95.99 % (area percent) of the total oil composition. Oil was rich in Oxygenated Monoterpenes (45.14 %), exhibited higher percentage of Camphor (22.60 %) followed by Camphene (12.78 %), Borneol (11.16 %), 1,8-Cineole (5.94 %), Acorenone (5.84 %) and α-Pinene (5.01 %). The principal constituents are hydrocarbons, ketones, alcohols, esters and aldehydes. The antioxidant activity of essential oil was investigated by measuring the decrease in absorption at 517 nm of 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) in a UV/visible spectrophotometer. The oil exhibited weak antioxidant activity by DPPH free radical scavenging bioassay (IC₅₀ = 83.8 mg/ml).