RESUMO
AIMS: In the present work, the Libyan wild-growing Thymus capitatus essential oil (EO) was evaluated for its biological properties. METHODS AND RESULTS: Carvacrol (68.19%) and thymol (12.29%) were found to be the main compounds of the oil. Antioxidant properties, determined by 2,2-diphenylpicrylhydrazyl (DPPH) assay, revealed that IC50 values were 119, 403 and 105 µg ml(-1) for oil, thymol and carvacrol respectively. Microdilution method showed strong antibacterial and especially antifungal potential. Tetrazolium (MTT) colorimetric assay indicated moderate cytotoxicity towards human cell lines MRC-5, HCT 116 and HT-29 (IC50 = 30-150 µg ml(-1)). In adhesion-inhibition assay oil and main compounds reduced adhesion of Escherichia coli and Listeria monocytogenes on colon cells HT-29 (51 and 39% of inhibition against L. monocytogenes and E. coli respectively). CONCLUSIONS: Essential oil of Th. capitatus showed moderate cytotoxic activity, together with excellent antimicrobial effect, in particular against fungi, and significant potential to reduce pathogen colonization in colon. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report that EO of Th. capitatus could protect against colonization of pathogens to colon epithelium. Thymus capitatus from Libya should be recognized as possible new source of natural antioxidants, antimicrobials as well as possible source of new chemotherapeutics.
Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Colo/microbiologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Thymus (Planta)/química , Anti-Infecciosos/química , Antioxidantes/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/fisiologia , Óleos Voláteis/química , Extratos Vegetais/químicaRESUMO
The chemical composition of essential oils from three Micromeria species: M. dalmatica Benth., M. albanica (Griceb. ex K. Mal) Silic and M. thymifolia (Scop.) Fritsch were investigated by GC and GC-MS and their antibacterial and antifungal activities against seven fungal and six bacterial species were evaluated. Biological assays showed strong fungitoxicity of oils from all three Micromeria spp., particularly M. albanica, against all fungi tested. Essential oils of these species also exerted antibacterial effect against Streptococcus aureus, Escherichia coli, Bacillus subtilis and Micrococcus luteus at low concentrations. Higher concentrations of essential oil of M. albanica and M. dalmatica were active against Gram-negative Pseudomonas aeruginosa, which could be due to the high content of piperitenone oxide.
Assuntos
Anti-Infecciosos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Lamiaceae/química , Fungos Mitospóricos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Antibacterianos , Anti-Infecciosos/química , Antifúngicos/química , Antifúngicos/farmacologia , Óleos Voláteis/química , Folhas de Planta/química , Óleos de Plantas/químicaRESUMO
The antifungal activity of Aniba rosaeodora, Laurus nobilis, Sassafras albidum and Cinnamomum zeylanicum essential oils were investigated against 17 micromycetes. Among the tested fungal species were food poisoning, spoilage fungi, plant and animal pathogens. In order to determine fungistatic and fungicidal concentrations (MIC and MFC) macrodilution and microdilution tests were used. Linalool was the main component in the essential oil of A. rosaeodora, while 1.8-cineole was dominant in L. nobilis. In sassafras essential oil safrole was the major component and in the oil of C. zeylanicum the main component was trans-cinnamaldehyde. The essential oil of cinnamon showed the strongest antifungal activity.