Activity of Medicinal Plants,Used by Native Populations from Sonora,Mexico, Against Enteropathogenic Bacteria

Antibacterial activities of methanol and hexane extracts of thirty plants, traditionally used to cure gastrointestinal diseases by six native groups living in Sonora, Mexico, were evaluated against four enteropathogenic bacteria: Salmonella typhimorium (ATCC14028), Shigella flexneri (ATCC 12022), Escherichia coli (ATCC 25922), Escherichia coli (ATCC 35218). The antimicrobial activity was determined using the standard Disk Diffusion Method (DDM) protocol, and assessed by the presence or absence of inhibition zones. Fifteen methanol and four hexane crude extracts had activity against at least one strain. Methanol extracts from Acacia constricta Benth (Mimosaceae), Lysiloma divaricata J.F. MacBride (Fabaceae), Lysiloma watsonii Rose (Fabaceae), and Pithecellobium dulce (Roxb.) Benth (Fabaceae) showed activity against all evaluated enteropathogenic bacteria. The methanol extract of Struthanthus haenkeanus Standley (Loranthaceae) had strong antimicrobial activity against S. flexneri. Only Coursetia glandulosa Gray (gum) (Fabaceae) and Mascagnia macroptera Niedensu (Malpighiaceae) hexane extracts had activity against enterophatogenic bacteria. This is the first evaluation of these medicinal plants against bacterial pathogens that cause gastrointestinal disorders, such as diarrhea and dysentery in the Mexican population.