Multi-drug resistant microbial infections caused by Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi represent a critical public health issue worldwide. Plant-derived agents are cre...Multi-drug resistant microbial infections caused by Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi represent a critical public health issue worldwide. Plant-derived agents are credible sources for search and development of alternative antimicrobials to fight these infections. This study describes the in-vitro antibacterial activity of plants extracts from 15 medicinal plants of the Cameroonian pharmacopeia against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi. Plants selected based on their ethnopharmacological uses were extracted by either maceration or decoction using distilled water, ethanol, methanol and ethylacetate. The afforded extracts were phytochemically screened for bioactive secondary metabolites. The microdilution method was used to assess the antibacterial activity. The two promising extracts were tested in combination using the cbeckboard technique. Eighty one extracts showed antibacterial activity with eight having minimum inhibitory concentrations below 2.5 mg/mL. Results from combination assays with extracts from Terminalia catappa and Gnidia glauca leaves showed synergistic effect against Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi and additive effect against Staphylococcus aureus. These extracts mainly contained saponins, tannins, glucosides, phenols, triterpenes and anthraquinones. These results support the ethnobotanical claims and indicate further directions for the investigation of plants extracts to develop alternative drugs against multi-resistant bacteria.展开更多
文摘Multi-drug resistant microbial infections caused by Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi represent a critical public health issue worldwide. Plant-derived agents are credible sources for search and development of alternative antimicrobials to fight these infections. This study describes the in-vitro antibacterial activity of plants extracts from 15 medicinal plants of the Cameroonian pharmacopeia against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi. Plants selected based on their ethnopharmacological uses were extracted by either maceration or decoction using distilled water, ethanol, methanol and ethylacetate. The afforded extracts were phytochemically screened for bioactive secondary metabolites. The microdilution method was used to assess the antibacterial activity. The two promising extracts were tested in combination using the cbeckboard technique. Eighty one extracts showed antibacterial activity with eight having minimum inhibitory concentrations below 2.5 mg/mL. Results from combination assays with extracts from Terminalia catappa and Gnidia glauca leaves showed synergistic effect against Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi and additive effect against Staphylococcus aureus. These extracts mainly contained saponins, tannins, glucosides, phenols, triterpenes and anthraquinones. These results support the ethnobotanical claims and indicate further directions for the investigation of plants extracts to develop alternative drugs against multi-resistant bacteria.