Antimicrobial Activities of Some Medicinal Plants Against Multiresistants Microorganisms Causing Urogenital Tract Infections in Cameroon

Urogenital tract infections remain a serious global treat especially in women. The control of these infections is increasingly complicated due to development of resistance against available drugs. Therefore a perpetual search of new antimicrobial molecules is needed to face the challenge of microbial resistance. This study was initiated to screen the antimicrobial activities of methanol extracts of nine Cameroonian medicinal plants, used for the treatment of infectious diseases, against multiresistant pathogens isolated from urogenital infected patients. The plants included: Cussonia arborea, Dissotis longipetala, Lonchocarpus sepium, Nauclea pobeguinii, Picralima nitida, Rumex abyssinicus, Rumex berqueatii, Sapium ellypticum, Psorospermum febrifigum, They were tested on seven strains including six clinical isolates (Escherichia coli, Proteus vulgaris, Providencia stuartii, Pseudomonas aeruginosa, Staphylococcus saprophiticus, Candida krusei) and one reference strain (E. coli JM109). Clinical strains were checked for their multiresistance using disc diffusion method. The antimicrobial activities were determined by agar well diffusion method. MICs were determined using microdilution assay. The phytochemical screening of plants was also done. All the bacteria strains were found to be multidrug-resistant (MDR) against at least 7 of the 12 antibiotics tested. Antimicrobial activities demonstrated that 6/9 (SE, DL, RA, RB, PN, LS) plants were active on at least six microorganisms. MICs ranged from 0.125 to 128mg/ml for crude extracts, from 0.5 to 0.16µg/ml for gentamicin and was 0,002mg/ml for fluconazole. One extract (NP) which showed limited results on agar, inhibited the growth of all the strains with MICs ranging from 1to 16mg/ml showing a limited activity of this extract on agar. We found that four extracts (SE, NP, RA, DL) have significant activities since they presented MICs ≤ 8mg/ml on at least 5 tested microorganism individually. Findings from phytochemical screening showed that most active extracts contain tannins, alkaloids and saponins which could be responsible of these activities.