Composition and Antimicrobial Activity of the Essential Oils of Two Origanum Species

Abstract
The essential oils obtained from the aerial parts of Origanum scabrum and Origaum microphyllum, both endemic species in Greece, were analyzed by means of GC and GC-MS. Forty-eight constituents were identified, representing 98.59 and 98.66% of the oils, respectively. Carvacrol, terpinen-4-ol, linalool, sabinene, α-terpinene, and γ-terpinene were found as the major components. Furthermore, both samples exhibited a very interesting antimicrobial profile after they were tested against six Gram-negative and -positive bacteria and three pathogenic fungi. Keywords: Origanum essential oils; O. scabrum; O. microphyllum; antimicrobial activities; GC-MS; carvacrol; terpinen-4-ol; linalool; sabinene; α-terpinene