Análisis del efecto antimicrobiano de doce plantas medicinales de uso ancestral en Ecuador

The specimens of plant species Lippia citriodora K (cedrón), Ambrosia artemisifolia L (altamisa), Taraxacum officinale Weber (diente de león), Ageratum conyzoides L (mastrante), Piper carpunya Ruiz & Pav (guaviduca), Borago officinalis L (borraja), Coriandrum sativum L (cilantro),Melissa officinalis L (toronjil), Cymbopogon citratus S (hierba luisa), Artemisia absinthium L (ajenjo), Momordica charantia L (achochilla) y Moringa oleífera Lam (moringa) were collected randomly in the towns of Santa Rosa and Machala, Ecuador. The leaves were washed, dried, ground and extracted by maceration with methanol; the filtrates concentrated by evaporation under reduced pressure. A diffusion technique in agar was used to determine the antimicrobial activity of the obtained methanolic extracts, by which they were tested against strains of Gram-positive (Staphylococcus aureus) and Gram negative bacteria (Escherichia coli and Paeruginosa), and a strain of fungus (Candida albicans). All extracts analyzed, except for those of Lcitriodora and A. conyzoides showed a bactericidal action against all bacterial strains tested, reflecting the importance of these species in the production of herbal medicines antibiotics. T. officinale and Pcarpunya showed a high antibacterial effect against E. coli; however, S. aureus did not show sensitivity to P. carpunya and L. citriodora extracts. The antifungal activity bioassay conducted to studied extracts against C. albicans, showed that all have high fungicidal action, except for T. officinale with less inhibitory effect of fungal growth. It can be inferred that these plants are a promising source of antimicrobial components of high pharmacological value.