Screening of Some Medicinal Plants Used in South-West Nigerian Traditional Medicine for Anti-Salmonella typhi Activity

Ten Nigerian medicinal plants used traditionally for the treatment of several ailments of both microbial and non-microbial origins were tested on multi-drug resistant S. typhi(MDR) strains of which six of them were active. The results revealed that both the aqueous and ethanol extracts of Terminalia avicennioides, Momordica balsamina, Combretum paniculatumand Trema guineensiswere effective on the MDR-S. typhistrains with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values ranging from 9.60 to 14 mcg/ml and 24 to 33 mcg/ml, respectively. Whereas, only the aqueous extracts of Morinda lucidaand Ocimum gratissimumwere found to be active against this pathogen with MIC and MBC values of 9.60 and 24 mcg/ml for M. lucida, 40 and 55 mcg/ml for O. gratissimum, respectively. There was no statistical significant difference (P > 0.05) between the activity of each plant extract and the decoctions prepared from them. All the six active plants showed positive reactions to alkaloids, tannins, flavonoids and anthraquinones but in variable degrees. All but M. balsamina, indicated the presence of saponin.