ABSTRACT
Phytochemical investigation of the ethanol extract of the stem bark of Hypericum lanceolatum Lam. (Guttifereae)afforded eight known compounds including 2,2ʹ,5,6ʹ-tetrahydroxybenzophenone (1), 5-hydroxy-3-methoxyxanthone(2), 3-hydroxy-5-methoxyxanthone (3), betulinic acid (4), hydroquinone (5) 6,7-dihydroxy-1,3-dimethoxyxanthone(6), calophyllumin A (7), and 1,3,5,6-tetrahydroxy-4-prenylxanthone (8). Compound 1 was submitted to acetylationreaction to give 5-acetoxy-2,2ʹ,6ʹ-trihydroxybenzophenone (9), a new hemisynthetic derivative. Compounds 5 and8 were isolated for the first time from this plant. The structures were established by extensive analysis of their massspectrometry and nuclear magnetic resonance (NMR) spectroscopic data and comparison with those from the literature.The isolated compounds (1, 2, 4, 5, and 8) and the derivative of benzophenone (9) were tested for their antipromastigoteand cytotoxic activities against visceral leishmaniasis parasite Leishmania donovani and macrophage RAW 264.7 cellline, respectively. Compound 9 was the most active with an IC50 value of 6.1 µg/ml, while compounds 1, 2, 4, and 8were moderately active with IC50 values ranging from 11.4 to 34.8 µg/ml against L. donovani and were not cytotoxicexcept compound 5 that was very toxic and not active. The findings of the present study suggested that compounds 1,2, 4, and 8 could be considered as a potential source of therapeutic medicine for the treatment of leishmaniasis.
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 present research evaluated the antidiabetic and antioxidant properties of M. lucida stem bark [50 and 500mg/kg] and glibenclamide [25mg/kg, standard drug] in acute [Oral glucose tolerance test] and sub-acute [Streptozotocin 60mg/kg, i.p. diabetic model] administration. A group of healthy rats constituted the normal control. The sub-acute experiment lasted 28 days during which water, food intake and weight gain were measured and biochemical parameters analyzed in both plasma and erythrocytes at the end of the experiment. The chemical substances present in M. lucida bark extract were determined. In the Oral glucose tolerance test, the reduction of blood glucose level was statistically significant for both M. lucida extracts and glibenclamide. However, in the diabetic rats acute administration of 500mg/kg extract had better blood sugar lowering effect than glibenclamide, which was better than 50mg/kg extract. Streptozotocin diabetic animal model was characterized by a decrease in weight gain, erythrocyte SOD and CAT activities and an increase in water and food consumption, lipid peroxidation, cholesterol, triglycerides, plasma glucose, creatinine and urea concentrations, and transaminases activities. M. lucida extract and glibenclamide significantly prevented the alteration of these parameters, thus indicating a corrective effect on diabetes and its complications. This study justifies the traditional claim and provides a rationale for the use of M. lucida to treat diabetes. Its antioxidant properties may serve to curb oxidative stress and hence prevent the diabetic complications related to oxidative stress. Chemical substances, which may be accountable for the antidiabetic and antioxidant properties of M. lucida were detected in the aqueous extract of M. lucida bark