Essential Oil Composition and Antioxidant Activity of Calamintha officinalis Moench

Calamintha officinalis Moench (COM) is an aromatic herb from Lamiaceae family with high similarities to the common mints not only in its appearance but also in terms of aroma. The aim of this research was to evaluate antioxidant activity of plant extract and to identify constituents of its essential oil. The plant samples were collected from North of Iran (Guilan, Lahijan) and its identity was certified by a systematic botanist in University of Guilan. The dried leaves of COM were subjected to hydro-distillation using a Clevenger-type apparatus and the composition of the essential oil was analyzed by gas chromatography–mass spectrometry (GC-MS). It was found that major constituents of oil were trans-caryophyllene (8.55%), isomenthol (2.98%), tetrahydrolinalyl acetate (2.96%), and pinene (2. 24%). In other part of the research, the biological activities of superoxide dismutase (SOD) and catalase (CAT) were assayed by in extracts of the leaves spectrophotometric method. It was found the extract contained a considerable superoxide anion radical scavenging power. On the other hand, the biological activity of CAT in extract of COM leaves showed gradual increase during time with a gentle slope indicating an increase in oxidative stress. The result of our study on Calamintha revealed the existence of a specific component of the essential oil (trans-caryophyllene) that has not been reported by other researchers. In addition to the antioxidant property that was confirmed in this study, the major component of its essential oil was found to be an antimicrobial agent.