Elionurus mutycus from north of Argentina: evaluation of the antibacterial activity of three essential oil chemotypes

CACCIABUE M.; GALLUCCI N.; CORDERO GABRIELLI P.; KOLB N.; DEMO M.; SABINI L.

Villa Giardino, Córdoba

Jornada; XV Biennial Scientific Meeting in the 70th Anniversary; 2005

Sociedad de Biología de Córdoba

Elionurus mutycus (Aibé) is the most abundant pasture grass in the northeast region of Argentina. Its industrial applications have been described, nevertheless there are no information about the antimicrobial capacity of its essential oil (EO) that can be conditioned by its chemical composition. The objective of this work was to evaluate the in vitro antimicrobial activity of the 3 biotypes in E. muticus, against Gram+ and Gram- bacteria. The EO was obtained by hydrodistillation, analyzed by gaseous chromatography to determinate their chemotypes: Geraniol, Acorenona and Citral. The antimicrobial activity was evaluated against Gram+ bateria: S.aureus ATCC, B.cereus, and E.faecalis ATCC, Gram-: P.mirabilis, P.aeruginosa, and E. coli, using the disk diffusion method (DD) and microdilution technique (MDT). For the DD, 100μl of microbial cultures (106 ufc/ml) were seeded in Petri plates containing Müller-Hinton agar. Then, disks of paper absorbed with 10μl of each EO were added. After 30 min. to ambient temperature, were incubated to 37ºC by 24 h. The inhibition halos were measured. The CIM was determined by DD and MDT for the active oils, making dilutions two fold of them in agar-agar (Mann and Markham 1997). All biotypes exerted antimicrobial action. The G+ were more sensitive than G-, (100% vs 50%), whit 14.13 and 9.25 mm of halo inhibition respectively. The North of Argentina presents biotypes of E.mutycus whose EO could be applied to control microbial strains implied in alimentary contamination and human and animals pathologies. Particularly P.aeruginosa that was highly sensitive to EO citral chemotype with a CIM=1/64. Data reveal their importance for the possible control of this pathogen.