Antimicrobial and antioxidant activity of the essential oil and methanol extracts of Thymus pectinatus Fisch. et Mey. Var. pectinatus (Lamiaceae).
The essential oil, obtained by using a Clevenger distillation apparatus, and water-soluble (polar) and water-insoluble (nonpolar) subfractions of the methanol extract of Thymus pectinatus Fisch. et Mey. var. pectinatus were assayed for their antimicrobial and antioxidant properties. No (or slight) antimicrobial activity was observed when the subfractions were tested, whereas the essential oil showed strong antimicrobial activity against all microorganisms tested. Antioxidant activities of the polar subfraction and the essential oil were evaluated using 2,2-diphenyl-1-picrylhydrazyl, hydroxyl radical, superoxide radical scavenging, and lipid peroxidation assays. The essential oil, in particular, and the polar subfraction of the methanol extract showed antioxidant activity. The essential oil was analyzed by GC/MS, and 24 compounds, representing 99.6% of the essential oil, were identified: thymol, gamma-terpinene, p-cymene, carvacrol, and borneol were the main components. An antimicrobial activity test carried out with fractions of the essential oil showed that the activity was mainly observed in those fractions containing thymol, in particular, and carvacrol. The activity was, therefore, attributed to the presence of these compounds. Other constituents of the essential oil, such as borneol, gamma-terpinene, and p-cymene, could be also taken into account for their possible synergistic or antagonistic effects. On the other hand, thymol and carvacrol were individually found to possess weaker antioxidant activity than the crude oil itself, indicating that other constituents of the essential oil may contribute to the antioxidant activity observed. In conclusion, the results presented here show that T. pectinatus essential oil could be considered as a natural antimicrobial and antioxidant source.
Vardar-Unlü
Gülhan
G
Department of Microbiology, Faculty of Medicine, Cumhuriyet University, Sivas, 58140 Turkey. unlum@yahoo.com
Candan
Ferda
F
Sökmen
Atalay
A
Daferera
Dimitra
D
Polissiou
Moschos
M
Sökmen
Münevver
M
Dönmez
Erol
E
Tepe
Bektaş
B
D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D001713:Biphenyl Compounds; D001892:Camphanes / Q000032:analysis; D005591:Chemical Fractionation; D000081005:Cyclohexane Monoterpenes; D000081007:Cymenes; D016166:Free Radical Scavengers / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry; D019686:Lamiaceae / Q000737:chemistry*; D015227:Lipid Peroxidation / Q000187:drug effects; D000432:Methanol; D039821:Monoterpenes / Q000032:analysis; D009822:Oils, Volatile / Q000737:chemistry / Q000494:pharmacology*; D010851:Picrates / Q000737:chemistry; D010936:Plant Extracts / Q000494:pharmacology*; D010938:Plant Oils / Q000494:pharmacology; D013729:Terpenes / Q000032:analysis; D013943:Thymol / Q000032:analysis
D000900:Anti-Bacterial Agents; D000975:Antioxidants; D001713:Biphenyl Compounds; D001892:Camphanes; D000081005:Cyclohexane Monoterpenes; D000081007:Cymenes; D016166:Free Radical Scavengers; D039821:Monoterpenes; D009822:Oils, Volatile; D010851:Picrates; D010936:Plant Extracts; D010938:Plant Oils; D013729:Terpenes; C007210:4-cymene; D013943:Thymol; C018669:gamma-terpinene; C073316:carvacrol; C004931:1,1-diphenyl-2-picrylhydrazyl; C022871:isoborneol; D000432:Methanol