Chemical diversity in essential oil composition of Mentha longifolia (L.) Hudson subsp typhoides (Briq.) Harley var. typhoides from Turkey

The essential oil obtained by hydro-distillation of leaf and flower in Mentha longifolia (L.) Hudson subsp. typhoides (Briq.) Harley var. typhoides (Lamiaceae) collected on the flora of Tokat (Black Sea region of Turkey) has been investigated by gas chromatography (GC) and GC-mass spectrometry (GC-MS). As a result of cluster analysis of oil components, four chemotypes - piperitone oxide (PO), piperitone oxide/piperitenone oxide (PO/PNO), p-menthone/piperitone oxide (MN/PO) and trans-dihydrocarvone (DC) - were characterized in both leaf and flower oils. Piperitenone oxide/piperitone oxide (PNO/PO), piperitone oxide/p-menthone/pulegone (PO/MN/PL) and linalool (LI) are distinguished in flower oil, while piperitone oxide/carvacrol/thymol (PO/CR/TH), linalool/isomenthone (LI/IMN) and linalool/piperitone oxide (LI/PO) are distinguished in leaf oil. Samples of the chemotypes have been conserved in botanical garden of Agricultural Research and Application Center in Gaziosmanpasa University for biological activity studies in future.