In this study, thin-layer chromatography-direct bioautography (TLC-DB) was used for guiding the isolation and identifcation of antibacterial constituents of Thymus vulgaris L. ethanol extract. This TLC-bioassay method enables the separation and detection of active components directly on the surface of chromatographic plates. They can be identifed by comparison with reference substances or using physicochemical methods, preferably spectroscopic ones (liquid chromatography-tandem mass spectrometry [LC-MS/MS], in the presented paper). The described method belongs to the e-ect-directed analyses (EDA). Seven bacterial strains were used as test organisms, both pathogenic and nonpathogenic, including methicillin-resistant Staphylococcus aureus as well as luminescent bacteria like Aliivibrio fscheri. Five fractions with the widest antimicrobial spectra were detected using TLC-DB, isolated by semi-preparative TLC and subjected to LC-MS/MS analyses. Finally, two bioactive components were tentatively identifed, basing on their fragmentation pattern, as eriodictyol and 4,4′dihydroxy-5,5′diisopropyl-2,2′dimethyl-3,6-bifenylodion.
- Antibacterial activity
- Liquid chromatography-quadrupole time-of-flight mass spectrometry
- Thin-layer chromatography-direct bioautography
- Thymus vulgaris L.
ASJC Scopus subject areas
- Analytical Chemistry
- Clinical Biochemistry