Chemical composition and biological activities of essential oils of endemic Thymus leucostomus Hausskn. et Velen

Abstract

The chemical composition, antimicrobial and antioxidant properties of the essential oils from the leaves of endemic Thymus leucostomus naturally grown in Turkey were investigated and chemical differences were discussed by means of chemotaxonomy. Twenty-six components were identified representing 98.8% of the oils. The main compounds in the essential oil of T. leucostomus were: o-cymene (30.6%), carvacrol (9.6%), thymol methyl ether (7.2%), limonene (6.8%). Essential oil was screened for their antimicrobial activities against 7 bacteria and 2 yeast species by using disc-diffusion and MIC procedure. The essential oil showed higher effectiveness against all the tested bacteria and yeast. The extract was observed to be much more effective in Gram-positive bacteria (especially, S. aureus ATCC 6538). In vitro antioxidant activity based on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical was evaluated for the essential oil, and it was found that the essential oil had good antioxidant activity in the range of the IC50= 5.42 ±0.8 μg/ml.

Chemical composition of the essential oil of Thymus longicaulis C. Presl. subsp. longicaulis

“…As well, o-cymene was also dominant for T. vulgaris in Brazil (Lemos et al, 2017). Elkiran and Avsar reported, o-cymene (30,62%), carvacrol (9.66%), isothymol methyl ether (7.22%), and limonene (6.88%) were the main components of the essential oil of T. leucostomus from the Sinop (Elkiran & Avsar, 2020). In our study, these components were absent.…”

“…It is characteristic that the breed has a high degree of hybridization (Baser et al, 1992a). This genus, which has a high polymorphic feature, is included in the Flora of Turkey with 39 species and 64 taxa, the endemism rate is 47% compared to the flora of Turkey (Elkiran & Avsar, 2020). Some of the thyme species show remarkable health benefits that can be endorsed due to their nutritional value.…”

“…: T. migricus; 2: T. fallax; 3: T. serpyllum; 4: T. pubescence; 5: T. trautvetteri; 6: T. transcaspicus; 7: T. carmanicus; 8: T. daenensis-1; 9: T. daenensis-2; 10: T. daenensis-3; 11: T. fedtschenkoi-1; 12: T. fedtschenkoi-2; 13: T. fedtschenkoi-3; 14: T. vulgaris-1(Tohidi et al, 2017); 15:T. transcaucasicus(Bektaş et al, 2016(1)); 16: T. dacicus(Petrović et al, 2017); 17: T. capitatus(Jemaa et al, 2017); 18: T. leucostomus(Elkiran & Avsar 2020); 19: T. longicaulis subsp. longicaulis; 20: T. nummularis(Bektaş et al, 2016(2)); 21: T. vulgaris-2(Myszka et al, 2016); 22: T. hyemalis; 23: T. zygis-1; 24: T. zygis-2(Carrasco et al, 2016); 25: T. lanceolatus(Khadir et al, 2016); 26-T. vulgaris-3(Benmoussa et al, 2016); 27-T. pulegioides(Vaičiulytė et al, 2017); 28: T. vulgaris-4; 29: T. citriodorus(Checcucci et al, 2016); 30: T. alternans(Vitali et al, 2016); 31: T. daenensis-4(Jarrahi et al, 2016); 32: T. bovei(Jaradat et al, 2016); 33: T. praecox ssp.…”

LC‐MS/MS and GC‐MS profiling, antioxidant, enzyme inhibition, and antiproliferative activities of Thymus leucostomus Hausskn. & Velen. extracts

“…For example, essential oils extracted from Thymus leucostomus growing in Turkey are rich in monoterpenes with carvacrol, cymene, thymol, α‐terpinyl acetate, borneol, and linalool as major compounds. [ 23,24 ] Additionally, the essential oil from the leaves is reported to possess high antibacterial, antifungal, and antioxidant activities. [ 23 ]…”

“…[ 23,24 ] Additionally, the essential oil from the leaves is reported to possess high antibacterial, antifungal, and antioxidant activities. [ 23 ]…”