Background: Typhoid fevers and urogenital infections continue to be
serious health problems in developing countries. In our search for
therapeutic agents from natural sources with potential for the
treatment of typhoid fevers and urogenital infections, extract and
compounds were obtained from Crinum purpurascens and tested.
Methods: Two alkaloids
(4,5-ethano-9,10-methylenedioxy-7-phenanthridone or hippadine (1) and
4,5-ethano-9-hydroxy-10-methoxy-7-phenanthridone or pratorimine (2))
and one steroid (â-D -glucopyranoside of sitosterol (3)) were
isolated from the CH2Cl2/MeOH (1:1) leaf extract of Crinum purpurascens
and screened for antibacterial activity using both agar diffusion and
broth dilution techniques. Results: For the CH2Cl2/MeOH extract, the
MIC values obtained were 3 mg/ml (against P. aeruginosa), 4 mg/ml
(against E. coli, K. pneumoniae and S. aureus) and 6 mg/ml (against S.
typhi and S. paratyphi B), whereas the MBC values varied between 7 and
12 mg/ml. For compound 1, the MIC values varied between 200 and 250
µg/ml, whereas the MBC value was 300 µg/ml against all the
bacteria strains used. Compound 2 did not show any antimicrobial
activity against these bacteria strains. For compound 3, the MIC values
varied between 250 and 300 µg/ml, whereas the MBC values were 300
µg/ml (against S. typhi and S. paratyphi B) and > 300
µg/ml (against the other bacteria strains). Conclusion: These
data suggest that C. purpurascens leaf extract contains antibacterial
agents which could be used in the treatment of typhoid fevers and
urogenital infections