Naslov
Composition and antioxidant activity in vitro of the essential oil of Thymus bracteosus in comparison to Thymus vulgaris

Autori
Ercegovac, Ozren ; Pfeifhofer, Hartwig W. ; Maleš, Željan ; Plazibat, Miško ; Brantner, Adelheid H.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Izvornik
50th Annual Congress of the Society for Medicinal Plant Research &#8211 ; Book of Abstracts / - Barcelona : CITA Publicaciones y Documentacion, 2002

Skup
50th Annual Congress of the Society for Medicinal Plant Research

Mjesto i datum
Barcelona, Španjolska, 08.09.2002. - 12.09.2002

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Thymus bracteosus; Thymus vulgaris; essential oil; antioxidant activity

Sažetak
The composition of the essential oil and the antioxidant properties of the dried herbs of Thymus bracteosus Vis. ex Benth. (Lamiaceae), a plant endemic to the Dinaric Karst, were investigated to find out if T. bracteosus can be used as herbal drug in the same way as T. vulgaris. The composition of the essential oil was analysed by GC/FID and GC/MS techniques. A data base was used for automatic identification of GC/MS peaks, linear retention indices were compared with published data ot authentic compounds. GC/MS analysis of T. bracteosus essential oil (yield after hydrodestillation 0.06%) revealed the presence of 83 compounds. Out of them 65 substances were identified, representing 92% of the total components. The major compounds of the oil are a-pinene (6.3%), myrcene (7.1%), b-caryophyllene (9.6%), trans-b-farnesene (6%) and germacrene-D (11.4%). Analysis of T. vulgaris (yield after hydrodestillation 2.5%) showed the presence of 80 compounds, 64 of which were identified, representing 96.8% of the total compounds. The main constituents are p-cymene (37.8%) and thymol (36.7%). Differences of the essential oils of the two investigated plant species were also caused by the variation of the content of monoterpenes (T. bracteosus 28.9%, T. vulgaris 95.1%) and sesquiterpenes (T. bracteosus 62.2%, T. vulgaris 1.1%). As T. bracteosus is not fulfilling the requirements of the pharmacopoeias (DAB, ÖAB, Ph. Helv.: yield at least 1.2% and 1.5% resp.) it cannot be used pharmaceutically in the same way as T. vulgaris. The essential oils of the two Thymus species were also investigated on their radical scavenger capacity measuring photometrically the disappearance of DPPH (T. vulgaris IC50 15.88 mg/ml, reference rutin IC50 3.01 mg/ml). Furtermore, the ability of the test samples to inhibit peroxidation of membrane lipids was tested (T. vulgaris IC50 44.20 mg/ml, reference fisetin IC50 7 mg/ml). The essential oil of T. bracteosus did not show any antioxidant activity in both test systems.

Izvorni jezik
Engleski

Znanstvena područja
Farmacija

POVEZANOST RADA