Content and composition of the essential oil of Thymus serpyllum L. growing wild in Estonia.

OBJECTIVE

The aim of this work was to analyze the essential oil content and its composition in the drug (Serpylli herba) of wild thyme (Thymus serpyllum L.) originating from 20 different natural places of growth in Estonia.

METHODS

The quantitative content of essential oil was determined according to the method of European Pharmacopoeia. Gas chromatographic analysis of essential oils was carried out using a gas chromatography with flame ionization detector on two fused silica capillary columns with bonded stationary phases NB-30 and SW-10. The identification of the oil components was accomplished by comparing their retention indices on two columns with the retention indices values of standard compounds, with our retention indices data bank and with literature data. The results obtained were confirmed by gas chromatography / mass spectrometry.

RESULTS

The content of essential oil is between 0.6 and 4 ml/kg and usually is not in conformity with European Pharmacopoeia standard (3 ml/kg). There were 55 components identified in the essential oil of wild thyme of Estonian origin. Differently from the data in the literature of foreign countries, thymol and carvacrol are not the main components of the essential oil of wild thyme growing in Estonia. The main components here are (E)-nerolidol, caryophyllene oxide, myrcene, (E)-beta-caryophyllene and germacrene D.

CONCLUSIONS

In Estonia, the (E)-nerolidol-caryophyllene oxide, (E)-nerolidol-myrcene and myrcene chemotypes of wild thyme drug are distinguishable.