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Composition of the essential oils of satureja abyssinica ssp. abyssinica and satureja paradoxa / Ketema Tolossa in The journal of essential oil research, Vol. 19 N°3 (Mai/Juin 2007) 

Public ISBD [article]  in The journal of essential oil research > Vol. 19 N°3 (Mai/Juin 2007) . - pp. 295-300 Titre : Composition of the essential oils of satureja abyssinica ssp. abyssinica and satureja paradoxa : Their antimicrobial and radical scavenging activities Type de document : texte imprimé Auteurs : Ketema Tolossa, Auteur ; Kaleab Asres, Auteur ; Fathy K. El-Fiky, Auteur Année de publication : 2007 Article en page(s) : pp. 295-300 Note générale : Génie Chimique Langues : Anglais (eng) Mots-clés : Satureja  abyssinica  subsp.  abyssinica  Satureja  paradoxa  Lamiaceae  Essential  oil  composition  Cis-piperitone  oxide  Pulegone  Isomenthone  Antimicrobial  activity  Antioxidant  activity Résumé : The essential oils of fresh aerial parts of Satureja abyssinica (Benth.) Briq. ssp. abyssinica and Satureja paradoxa (Vatke) Engl. collected in Ethiopia were analyzed by gas chromatography (GC/FID) and gas chromatography-mass spectrometry (GC/MS). The results of the analyses indicated that the components of the two oils are similar qualitatively with significant quantitative differences. Twenty-three compounds comprising 96.9% of the total peak area were identified in S. abyssinica ssp. abyssinica oil with the monoterpene ketones pulegone (43.5%) and isomenthone (40.7%) as major components. The oil of S. paradoxa was found to contain twenty-six compounds comprising 92.0% of the total oil with the major components being cis-piperitone oxide (45.3%), pulegone (9.3%) and piperitenone oxide (8.1%). The in vitro antimicrobial activity of the oils was studied against some medically important pathogens including Gram positive and Gram negative bacteria as well as some fungal strains using standard agar-well diffusion technique. Both oils exhibited significant activity against most of the bacteria and fungi used in the study with minimum inhibitory concentration (MIC) values ranging from 0.50 to 4.00 μL/mL, against the bacteria, and 0.19 to 3.00 μL/mL, against the fungi. Comparison of their activity with standard antibacterial and antifungal agents revealed that both oils were more active against Streptococcus pyogenes than the standard antibiotic amoxicillin. Moreover, the oil of S. paradoxa displayed a powerful activity against Candida albicans and Trichophyton mentagraphytes with growth inhibition zone greater than that of the standard antifungal agent ketoconazole. The oils were also tested for their antioxidant activity in diphenylpicrylhydrazyl (DPPH) assay and showed a dose dependant free radical scavenging activity with IC50 values of 1.8 μL/mL (S. abyssinica subsp. abyssinica) and 1.6 μL/mL (S. paradoxa). ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2007.9699285#.UWu2EkqC5mM [article] Composition of the essential oils of satureja abyssinica ssp. abyssinica and satureja paradoxa : Their antimicrobial and radical scavenging activities [texte imprimé] / Ketema Tolossa, Auteur ; Kaleab Asres, Auteur ; Fathy K. El-Fiky, Auteur . - 2007 . - pp. 295-300. Génie Chimique Langues : Anglais (eng) in The journal of essential oil research > Vol. 19 N°3 (Mai/Juin 2007) . - pp. 295-300 Mots-clés : Satureja  abyssinica  subsp.  abyssinica  Satureja  paradoxa  Lamiaceae  Essential  oil  composition  Cis-piperitone  oxide  Pulegone  Isomenthone  Antimicrobial  activity  Antioxidant  activity Résumé : The essential oils of fresh aerial parts of Satureja abyssinica (Benth.) Briq. ssp. abyssinica and Satureja paradoxa (Vatke) Engl. collected in Ethiopia were analyzed by gas chromatography (GC/FID) and gas chromatography-mass spectrometry (GC/MS). The results of the analyses indicated that the components of the two oils are similar qualitatively with significant quantitative differences. Twenty-three compounds comprising 96.9% of the total peak area were identified in S. abyssinica ssp. abyssinica oil with the monoterpene ketones pulegone (43.5%) and isomenthone (40.7%) as major components. The oil of S. paradoxa was found to contain twenty-six compounds comprising 92.0% of the total oil with the major components being cis-piperitone oxide (45.3%), pulegone (9.3%) and piperitenone oxide (8.1%). The in vitro antimicrobial activity of the oils was studied against some medically important pathogens including Gram positive and Gram negative bacteria as well as some fungal strains using standard agar-well diffusion technique. Both oils exhibited significant activity against most of the bacteria and fungi used in the study with minimum inhibitory concentration (MIC) values ranging from 0.50 to 4.00 μL/mL, against the bacteria, and 0.19 to 3.00 μL/mL, against the fungi. Comparison of their activity with standard antibacterial and antifungal agents revealed that both oils were more active against Streptococcus pyogenes than the standard antibiotic amoxicillin. Moreover, the oil of S. paradoxa displayed a powerful activity against Candida albicans and Trichophyton mentagraphytes with growth inhibition zone greater than that of the standard antifungal agent ketoconazole. The oils were also tested for their antioxidant activity in diphenylpicrylhydrazyl (DPPH) assay and showed a dose dependant free radical scavenging activity with IC50 values of 1.8 μL/mL (S. abyssinica subsp. abyssinica) and 1.6 μL/mL (S. paradoxa). ISSN : 1041-2905 En ligne : http://www.tandfonline.com/doi/abs/10.1080/10412905.2007.9699285#.UWu2EkqC5mM