Chemical composition and antimicrobial activities of essential oils (EO) extracted from leaves of Lippia rugosa A. Chev against foods pathogenic and adulterated microorganisms

摘要

Alternative natural additives are needed in order to guarantee food safety in preservation against foods pathogenic and adulterated microorganisms. Aromatic plants are traditionally employed for seasoning and prolongation of shelf life of food. The majority of their properties are due to the essential oils produced by their secondary metabolism. Great interest is given to these oils by the industry and scientific research. The essential oils obtained by hydrodistillation of leaves of?Lippia rugosa?A. Chev (Verbenaceae), collected respectively at N’dali and Gbegourou (Borgou, Northern Benin) was analyzed using capillary GC and GC/MS. The aim of the present work was to evaluate some antibacterial and antifungal activities parameters as minimum inhibitory concentration (MIC) and mycelial growth inhibition, of these essential oils (Eos) against?Escherichia coliATCC 25922,?Staphylococcus aureus?ATCC 25923 and mould strains as?Fusarium oxysporum,?Penicillium digitatum,?Aspergillus ochraceus?and?Aspergillus?parasiticusspecies isolated from foods stuffs. The main components of EOs are Germacrene D (43.5%), trans-?-caryophyllene (17.4%), in the species from N’dali contrary with the results observed for Gbegourou specie which showed Germacrene D (43.7%), Z-?-caryophyllene (16.4) and α-cadinol (6.5%). The MICs ranged from 0.44 to 0.88 mg.ml-1?for both bacteria species. The two essential oils extracted from leaves of?Lippia rugosa?have shown a fungistatic activity against the strains of?A. ochraceus,?A. parasiticus,?F. oxysporum?and?P. digitatum?at the concentrations ranged from 0.25 to 2.0 μl.ml-1. Results obtained in the present study indicate the possibility of exploiting?Lippia rugosa?Eo in the fight against strains of?Fusarium, Penicillium and Aspergillus?species?responsible for biodeterioration of foods stuffs.