title: In vitro antimicrobial and antioxidant activity of acetone and methanol extracts from Thymus leucotrichius (Lamiaceae).
abstract: OBJECTIVE
  Thymus species has been used as tonic and herbal tea, antiseptic, antitussive, carminative, antioxidant, anti-inflammatory and antimicrobial activities. The acetone and methanol extracts of Thymus (T.) leucotrichius (Labiatae/Lamiaceae) was examined for antimicrobial and antioxidant properties.
  
  
  METHODS
  The antioxidant properties of acetone and methanol extracts of Thymus leucotrichius were investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH)/nitric oxide (NO) radical scavenging activity, reducing power and total phenolic substance analysis. Antibacterial, antiyeast and antifungal activity of the plant extracts were tested using the disc diffusion method.
  
  
  CONCLUSIONS
  Results showed that IC50 of Thymus leucotrichius acetone and methanol extracts that scavenged 50% of the DPPH radical in the medium was found to be 109.72 microg/ml, 43.53 microg/ml, respectively. It was found that IC50 of Thymus leucotrichius acetone and methanol extracts which scavenged 50% of the NO radical in the medium was 180.56 microg/ml, and 67.34 microg/ml, respectively. In the Thymus leucotrichius acetone and methanol extracts (1 mg), 35.64 microg and 51.78 microg pyrocatechol equivalents of phenols were detected, respectively. Neither acetone nor methanol extract possessed activity towards Proteus vulgaris, Rhodotorula rubra, Candida albicans, Aspergillus parasiticus and Aspergillus niger. Acetone extract was the most active on Bacillus cereus and Bacillus megaterium. The sentivity was also observed against towards Escherichia coli H7:O157, Kluvyeromyces fragilis and Fusarium proliferatum when acetone extract used. The methanol extract also displayed more or less similar inhibitory activity towards the test microorganisms. Kluvyeromyces fragilis was resistant to methanol extract of the species unlike acetone extracts of the species. However, the fungus Fusarium proliferatum was markedly inhibited by the methanol extract of test species at 1000 microg and above. Significant inhibitory activities of the two extracts were based upon the increasing dose-dependent level.
authors.affiliation: Department of Biology, Faculty of Science and Arts, Osmaniye Korkut Ata University, Osmaniye, Turkey. zeynepulukanli@osmaniye.edu.tr
authors.forename: Z
authors.initials: Z
authors.lastname: Ulukanli
authors.forename: Y
authors.initials: Y
authors.lastname: Cigremis
authors.forename: A
authors.initials: A
authors.lastname: Ilcim
mesh_terms: D000096:Acetone / Q000737:chemistry; D000890:Anti-Infective Agents / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D001419:Bacteria / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D005658:Fungi / Q000187:drug effects; D020128:Inhibitory Concentration 50; D000432:Methanol / Q000737:chemistry; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology*; D012997:Solvents / Q000737:chemistry; D046930:Thymus Plant / Q000737:chemistry*
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D010936:Plant Extracts; D012997:Solvents; D000096:Acetone; D000432:Methanol