ABSTRACT
Objective: To investigate the phytochemical constituents, antioxidant and anthelmintic activities of the crude methanol extract of Cissus populnea (C. populnea) rhizomes. Methods: Phytochemical screening was performed using standard protocols, and column chromatography of silica gel was used for the compounds isolation. DPPH antiradical scavenging assay was performed in order to evaluate the antioxidant activity. Total phenolic content was evaluated using the Folin-Ciocalteu assay. The anthelmintic activity was screened on the bovine adult male forms of parasitic nematode Onchocerca ochengi, by the in vitro evaluation of the inhibition of adult worm motility and mortality. Worms were incubated in the presence of different concentrations of the plant extract and effects on survival were monitored after 24 and 48 h. Results: The preliminary phytochemical screening revealed the presence of phenolic compounds, saponins, steroids, tannins, and terpenoids. Bergenin and a mixture of phytosterol, β -sitosterol and stigmasterol were isolated from this extract and were identified by nuclear magnetic resonance, mass spectrometry and by comparison with published data. The crude methanol extract of C. populnea rhizomes showed a strong DPPH antiradical activity with a good amount of total phenolic content ((20.69±2.13) g gallic acid equivalent/100 g of extract) and significant anthelmintic activity comparable to the standard drug ivermectin. Bergenin was found to be inactive even after 72 h of incubation. Conclusions: This study constitutes the first report on the anthelmintic activity of this plant and supports the traditional use of C. populnea as a natural antioxidant and anthelmintic.
ABSTRACT
The aim of this study was to isolate compounds from Cameroonian propolis extracts and to test their activities against bacteria isolated from carcass at the Yaoundé slaughterhouse. The n-hexane, ethyl acetate and ethanol extracts of propolis samples from Ngaoundal and Tala-Mokolo were separated by successive silica gel column chromatography to give six triterpenes. Their structures were determined as 25-cyclopropyl-3β-hydroxyurs-12- ene (7), cycloart-3β-hydroxy-12, 25(26)-diene (8), lup-20(29)-en-3-one (9), olean-12-en-3β, 28-diol (10), lup- 20(29)-en-3β-oate (13) and 3β-hydroxylup-20(29)-ene (14). Compounds 7 and 8 were new triterpene derivatives while 10 and 13 were isolated for the first time from propolis. The structures of all the compounds were established on the basis of spectroscopic analysis. Phytochemical screening of the methanol extract (5) revealed the presence of alkaloids, reducing compounds, coumarins, saponins and tannins accounting for its broad spectrum antibacterial activities. The six isolated compounds and crude extracts were tested for antimicrobial activity against some Gram negative bacteria. The methanol extract (5) of propolis samples was active against Escherichia coli and Pseudomonas aeruginosa (MIC: 0.2 mg/ml) whereas the isolated compounds 7, 8 and 10 exclusively exhibited antimicrobial activity against Salmonellas pp (MIC: 0.1-0.15 mg/ml). The MIC values of all the four propolis products were greater than that of the standard drug (Amoxicillin): 0.1-0.2 mg/ml versus 0.4 mg/ml. Nevertheless, further pharmacological and toxicity studies on experimental animals are necessary to establish the safety of the propolis products for its use as topical antimicrobial agents.