Antiviral iridoid glycosides from Clerodendrum myricoides.

The methanol root extract of Clerodendrum myricoides (Hochst.) Vatke afforded two new (1, 2) and two known (3, 4) iridoid glycosides. The structures of the isolated compounds were established based on NMR, IR, UV and MS data analyses. The crude extract and the isolated constituents were assayed for antiviral activity against the human respiratory syncytial virus (RSV) in human laryngeal epidermoid carcinoma (HEp-2) cells. The crude extract inhibited RSV infectivity at EC50 = 0.21 µg/ml, while it showed cytotoxicity against HEp-2 cells with CC50 = 9 µg/ml. Compound 2 showed 43.2% virus inhibition at 100 µM, while compounds 1 as well as 3 and 4 had only weak antiviral and cytotoxic activities.

Antibacterial and cytotoxic prenylated dihydrochalcones from Eriosema montanum.

Two new prenylated dihydrochalcones (1,2) and eighteen known secondary metabolites (3-20) were isolated from the CH2Cl2-MeOH (1:1) extracts of the roots, the stem bark and the leaves of Eriosema montanum Baker f. (Leguminosae). The structures of the isolated compounds were characterized by NMR, IR, and UV spectroscopic and mass spectrometric analyses. The structures of compounds 5, 10, 11 and 13 were confirmed by single crystal X-ray diffraction. The antibacterial activity of the crude extracts and the isolated constituents were established against Gram-positive and Gram-negative bacteria. Among the tested compounds, 1-4 and 10 showed strong activity against the Gram-positive bacterium Bacillus subtilis with minimum inhibitory concentration (MIC) ranging from 3.1 to 8.9 µM, as did the leaf crude extract with an MIC of 3.0 µg/mL. None of the crude extracts nor the isolated compounds were active against Escherichia coli. Compounds 1, 3 and 4 showed higher cytotoxicity, evaluated against the human breast cancer cell line MCF-7, with EC50 of 7.0, 18.0 and 18.0 µM, respectively. These findings contribute to the phytochemical understanding of the genus Eriosema, and highlight the pharmaceutical potential of prenylated dihydrochalcones.

Nutritional value assessment of umufumba: A Rwandan wild edible plant Mondia whytei (Hook. F).

This study reports findings on the macro- and micronutrient content of the root bark of Mondia whytei Skeels (Hook. F) (Asclepiadaceae), from five Rwandan different localities Northern part, and the nutritional content was found to vary locality of the plant. Vitamins were analyzed using high-performance liquid chromatography (HPLC). The vitamins analyzed included ß-carotene (fat soluble), niacin, riboflavin, and thiamine (water soluble) whose content was found to range from 4.4 to 73.5 µg/g dry matter. Atomic absorption spectrophotometry (AAS) was used to analyze calcium, iron, copper, manganese, magnesium, zinc, cadmium, and lead, whereas flame emission spectrophotometry (FES) was used for the determination of sodium and potassium. The highest mineral (mg/g of dry matter) was K (11.34-32.05), while the lowest was Pb (0.03-0.06). Mean total protein content was determined using the combustion method, and the mean percentage range was 4.7%-15.4%. The sugars (fructose, glucose, sucrose, and xylose) were analyzed by HPLC. There were significant differences (2.5-132.2 mg/g) in the free sugar contents. The results obtained in this study indicate that Mondia whytei Skeels (Hook. F) is rich in nutrients and can be developed for use as a food supplement since the nutrient contents are within the ranges recommended by FAO and WHO.