High Content Of Thymol Research Articles

Propolis volatiles characterisation from acaricide-treated and -untreated beehives maintained at Algarve (Portugal)

The variability of the volatile profile of 70 propolis samples from acaricide-treated and -untreated beehives maintained at Algarve (Portugal) was evaluated. Propolis samples were collected in three regions of Algarve at three different periods. Cluster analysis based on the propolis volatiles’ chemical composition defined two main clusters, not related to the time of year, collection site, altitude, temperature or humidity ranges, and was based mainly on the relative amounts of viridiflorol, n-tricosane and n-nonadecane for cluster I. Cluster II was mainly characterised by the high thymol content, followed by viridiflorol, n-tricosane and n-nonadecane. The presence of higher thymol levels in propolis samples from cluster II may reflect the long use of an acaricide with thymol as main active ingredient. All samples showed an intense rock-rose aroma supported by the presence of characteristic Cistus and labdanum oil volatile components. Given the nowadays frequent propolis household use, volatiles thorough characterisation may assist in its quality assessment.

Phytochemical composition of the essential oil, total phenolic content, antioxidant and antimicrobial activity in Iranian Satureja sahendica Bornm. at different ontogenesis conditions

The effects of different ontogenesis conditions (pre-flowering, full-flowering and post flowering) on the yield, essential oil composition, total phenolic content, antioxidant and antimicrobial activity of Satureja sahendica Bornm. was investigated. The essential oil was obtained from the aerial parts of the plant by hydro distillation and analyzed by gas chromatography (GC) and gas chromatography–mass spectrometry (GC-MS). In total, 33 components were identified in the essential oil of S. sahendica under different harvesting times, that represented 98.54 to 98.72% of the oils. The major components were thymol (28.76 to 42.24%), P-cymene (23.89 to 34.33%), γ-terpinene (13.78 to 19.37%) and myrcene (1.87 to 2.28). The highest essential oil yield was obtained in flowering stage. The highest thymol content was observed in the pre-flowering and the highest p-cymene and γ-terpinene contents as precursors of thymol and carvacrol were observed in flowering and post-flowering stages. Total phenolics and antioxidant activity of plant extracts were measured by the Folin-Ciocalteu and DPPH free radical scavenging assays, respectively. The total phenolic content under different ontogenesis conditions varied from 24.78 to 25.56 (mg gallic acid equivalent/g dw). IC50 values in the DPPH assay ranged from 7.85 to 8.34 μg/ml and the highest activity was observed in pre-flowering stage. Antimicrobial activity of the essential oil of S. sahendica was evaluated using the disc diffusion method; and minimum inhibitory concentrations (MIC) and minimum fungicidal/bactericidal concentrations (MFC/MBC) were recorded using the micro dilution method. This study confirms that the essential oil of S. sahendica possesses high antimicrobial activities in in vitro against Candida albicans and Staphylococcus aureus, two medically important pathogens. The maximum activity of S. sahendica oil was observed in the oil obtained at pre-flowering stage, against Gram-positive bacteria (S. aureus) and the yeast (C. albicans).

Antimicrobial activity of Thymus longicaulis C. Presl essential oil against respiratory tract pathogens

Thymus longicaulis C. Presl is a small aromatic perennial herb of Lamiaceae family and a typical representative of the Illyric-Mediterranean flora. This species is a traditional remedy for cold, flu, cough, nephritis and abdominal pain [1]. Present study aimed to evaluate composition of essential oil and its in vitro antimicrobial activity against major respiratory tract pathogens which show increasing resistance to commonly prescribed antimicrobials [2]. The yield of essential oil obtained by hydrodistillation from aerial plant parts was 12 ml/kg. According to the GC-MS analysis, a total of 41 compounds (99%) were identified. Thymol (46.3%), γ-terpinene (16.2%), thymyl methyl ether (11.4%), and p-cymene (9.4%) were the main components. Antimicrobial activity of the essential oil was determined using microdilution broth assay (tested concentrations were 0.2-25 mg/ml). Amoxicillin-clavulanate and fluconazole were used in order to control sensitivity of tested clinically isolated bacterial and yeast strains: Haemophilus influenzae, Neisseria meningitidis, Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes and Candida albicans. The essential oil exhibited antimicrobial activity against all tested pathogens. The most sensitive strains were H. influenzae and S. pneumoniae (MIC 0.78 mg/ml), while S. aureus was the most resistant (MIC > 25 mg/ml). Our results revealed that T. longicaullis from Croatia is rich in essential oil characterized by a high content of thymol. A strong antimicrobial effect of the essential oil proved in this study indicates on its huge potential in the treatment of respiratory tract infections.

Essential Oil Variation in Thymus daenensis subsp. daenensis Cleak Populations

The chemical composition of the essential oils in 11 populations of Thymus daenensis subsp. daenensis Cleak was evaluated using GC and GC/MS. Carvacrol, thymol and geraniol were found as the main constituents in the oils of the tested populations. Variation of the oils in populations was subjected to cluster analysis and three different chemotypes including carvacrol (47.3–80.1%), thymol (53.1–72.2%) and geraniol (65.6–75.7%) were identiified. Other important components were β-caryophyllene (1.7–9%), p-cymene (0.1–10.9%) and γ-terpinene (0.1–7.8%). Although Thymus is known as having high thymol content in its oil, it is revealed that T. daenensis subsp. daenensis has also a high potential for carvacrol and geraniol constituents in the oil.

Changes in Essential Oil Composition of Oregano (Origanum onites L.) due to Diurnal Variations at Different Development Stages

The composition of essential oil in plants was affected by genetical and environmental conditions, which is determined by growth region and harvesting time in terms of ontogenetical and diurnal variability. In the present study, aerial parts of Origanum onites were harvested at three different development stages (pre, full and post flowering) and six different times of the day (06:00, 10:00, 12:00, 16:00, 20:00 and 24:00 h). A total of twenty-six components were identified by GC-MS,The major component was carvacrol, followed by thymol, p-cymene and ?-terpinene. The content of carvacrol in the essential oil varied between 24.66 and 52.58% and the highest carvacrol content was obtained from 10:00 h at pre-flowering stages, thymol content changed between 2.80 and 23.77% and the highest thymol content was also obtained from 24:00 h at pre-flowering stages.

Composition and antibacterial activity of the essential oils contained in Algerian Origanum glandulosum (Desf.)

The composition of the essential oil isolated by hydrodistillation from the aerial parts of Origanum vulgare subsp. glandulosum (Desf.) growing wild in Algeria was determined by GC and 13C NMR. The oil was characterized by high thymol content (41–49.5%) and its antibacterial activity was tested against bacteria Gram (−) and Gram (+). The oil is very active against all bacteria tested except Pseudomonas which turned out to be very resistant.

Harvest Time Effecting on the Essential Oil Content and Compositions of Thymus vulgaris

The highest essential oil content (2.41 %) was extracted from the herb, produced at beginning of flowering stage, and the lowest amount (0.67 %) at seed ripening stage. The essential oils content of herb of plants harvested before flowering, full flowering, and at fruit set stage were: 1.59, 1.51 and 0.69 % respectively. GC and GC-MS analyses of the essential oil showed that harvest time had effect on the essential oil compositions of Thymus vulgaris. Twenty-four components were found in the essential oil extracted from the herb harvested before flowering stage. But 23, 21, 23 and 23 components in the essential oil extracted from the herbs, which were collected at beginning of flowering, full flowering, fruit set and at seed ripening stages respectively. The major component of the essential oil was thymol. The highest thymol content (57.1 %) was identified in the oil of the herb, which was collected before flowering stage and the lowest amount (48.0 %) harvested at seed ripening stage. Other essential oil constituents affected by harvest time were: y-terpinene (9.5–19.7 %), p-cymene (6.8–20.0 %), linalool (1.6–2.7 %), carvacrol (2.4–3.2 %), E-caryophyllene (1.4–2.2 %), a- terpinene (1.3–2.0 %), ß- pinene (1.3–1.8 %), and borneol (0.3–1.7 %).

Essential oils of the aerial parts of three Salvia species from Jordan: Salvia lanigera, S. spinosa and S. syriaca

The compositions of the essential oils of three Jordanian Salvia species, S. lanigera and S. spinosa from a desert climate, and S. syriaca from a Mediterranean habitat, were studied. All three oils are rich in monoterpene derivatives (68–73%). S. lanigera and S. spinosa showed a very high content of thymol, 54.9% and 68.9%, respectively. The main constituents of S. syriaca were thymol, α-pinene and isobornyl acetate (15.5%, 12.6% and 12.0%, respectively).

Essential oil composition is related to the natural habitats: Coridothymus capitatus and Satureja thymbra in NATURA 2000 sites of Crete

The study of essential oils obtained from Coridothymus capitatus and Satureja thymbra collected from different natural habitat types of 11 NATURA 2000 sites scattered all over Crete has shown that they are characterized either by a high amount of carvacrol (up to 75.7%) or thymol (up to 65.6%) or by a more or less equal amount of the two phenols. The results of a discriminant analysis with predefined groups the natural habitat types wherefrom the plants were collected have shown that the oils of both species collected from the dry dwarf-shrub formations of the lowland have a high carvacrol content whereas those collected from the more mesic timber or highland formations have a high thymol content. Furthermore, the results of this study introduce the use of natural habitat unit as a tool for the assessment of essential oil variation.

高濃度チモール含有根管充填材の基礎的研究

Safety evaluation was made on Biological canal paste (BCP), one of newly developed endodontic pastes used for Ultrasonic Bio-Mechanical Obturation System. BCP was characteristic of a high content of thymol to show extreme antimicrobic action. The basic biological tests on cytotoxicity, systemic toxicity, mutagenicity and dermal sensitization were carried out in this study. On potency of cell growth inhibition in vitro, BCP was as same as Canals-N^[○!R] and much less than Canals^[○!R]. As neither death nor toxic syndrome in mice was found from administration of BCP in oral maximal dose of 1.0mg/kg, it was estimated that LD_<50> of BCP should be not less than the value of 'slightly toxic' classified by Deichmann. BCP showed negative results in mutagenicity examined by Ames test, and also in delayed type allergenicity by Adjuvant and patch test. From the above it was suggested that BCP was possibly safe so far as it was used properly for dental therapy.

Antibacterial and antioxidant properties of Mediterranean aromatic plants

Eleven aromatic plants (lavender, thyme, winter savory, rosemary, sage, peppermint, chanomile, Roman chamomile, French tarragon, bitter and sweet fennel), typical of the Mediterranean area, were grown in Northern Italy and their essential oils obtained by steam distillation. The distilled oils were analysed for their antibacterial activities against 25 microorganisms and also for any antioxidant properties. The chemical composition of the essential oils was related to their effectiveness. Thyme and winter savory oils exhibited the greatest inhibition against the growth of all the tested organisms possibly due to the high content of thymol and carvacrol respectively. The Roman chamomile oil exhibited the highest antioxidant activity.