Antibacterial activity of two species of Larrea against Gram negative bacteria

ZAMPINI I. C; CUDMANI NORMA; VATTUONE M. A; SAMPIETRO A. R.; ISLA M. I

Tafí del Valle Tucumán.Argentina

Jornada; XIX Jornadas Científicas de la Sociedad de Biología de Tucumán”.; 2002

Sociedad de Biología de Tucumán

The importance of the development of new drugs with high antibacterial activity is without doubts. Alcoholíc extracts of 30 argentine p1ant specíes were in vitro assayed agaínst Gram negative bacteria by the agar diffusion method. Larrea cuneifolia and Larrea divaricata extracts were the most potent followed by E. uniflora and Z. punctata ethanolic extracts. The aím of this work was to compare the minimal inhíbitory concentration (MIC) values of L.cuneifolia and L. divaricata extracts against 57 antibiotic-resistant and sensible c1inical isolates of Gram negative species (E. coli,K. pneumoniae, P. mirabilis, E. cloaca, P. stuartii, S. marcescens, M. morganii, A. baumanii, P. aeruginosa, S. maltophilia, E. coli ATCC 35218, P. aeruginosa ATCC 27853, E. coli ATCC 25922). Tinctures were prepared according to Farmacopea Argentina with and without Polyclar AT. The MIC and MBC values were determined with a serial agar macrodilution and microplate serial dilution technique with all microorganisms. Larrea divaricata extracts were the most potent followed by Larrea cuneifolia (MIC values of 100 and 200 µg of phenolic compounds/ml respectively).