Comparative composition of four essential oils of oregano used in Algerian and Jordanian folk medicine

Abstract

The essential oils obtained from Origanum glandulosum Desf., collected from two different localities of north-eastern Algeria, Constantine and Jijel, and from O. syriacum var. syriacum grown at El-Aghwar (northern Jordan) and El-Shubak (southern Jordan), were analyzed by GC-MS. p-Cymene (6.6% and 7.5%) and γ-terpinene (13.4% and 14.5%) were found in O. glandulosum grown at Constantine and Jijel, respectively, in addition to the major components thymol (34.2%, 51.1%) and carvacrol (30.5%, 6.8%). The oil of O. syriacum L. var syriacum (Boiss.) Ietswaart from El-Shubak was mainly represented by thymol (51.8%) and carvacrol (34.4%), while the oil from El-Aghwar was a thymol-chemotype (72.4%), along with γ-terpinene (7.8%) and p-cymene (5.4%).