Antibacterial agents from the leaves of Crinum purpurascens herb (Amaryllidaceae)

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

Xanthine oxidase inhibitory activity of compounds from Chythrantus claneianus

Phytochemical investigation of the stem bark and the trunk of Chythrantus claneianus led to the isolation of six known compounds named β-sitosterol (1), umbelliferone (2), scopoletin (3), benjaminamide (4), β-sitosterol-3-O-β-D-glucopyranoside (5) and panconoside B (6). All these compounds were isolated for the first time from this plant species. The chemical structures of isolates were elucidated on the basis of 1 and 2 D-NMR spectra and other spectroscopic techniques including UV–vis, FT-IR, HR-ESIMS and HR-FABMS. The isolates were tested in vitro for their inhibitory properties towards xanthine oxidase enzyme. Compounds 2, 3 and 6 showed weak inhibitory activities on the enzyme with IC50 values ranging from 307 µM for compound 6 to 475 µM for compound 3, while the extract and compounds 1, 4 and 5 showed extremely weak activities with inhibition percentage less than 50%