1-1-diphenyl-2-picrylhydrazyl and plumbagin

Bioactive compounds, including phenols, flavonoids, and tannins, were quantified in leaves, stems and roots of methanol, n-butanol, diethyl ether and n- hexane extracts of Ceratostigina plumbaginoides Bunge. (Plumbaginaceae) ornamental plants. The antioxidant capacity was measured by the DPPH and linoleic acid assays. The total bioactive compounds, as well as the antioxidant capacities, were the highest in the leaves compared with stems and roots. The -methanolic, n-butanol, diethyl ether and n-hexane leaf extracts varied in their antibacterial and antifungal activities. In general, the most sensitive bacterium to leaf extracts was Bacillus cereus and the most resistant was Staphyllococcus aureus, while the most sensitive fungus was Aspergillusflavus and the most resistant one was Penicillium ochrochloron. As the methanolic leaf extract was the most active, it was subjected to column chromatography and two compounds were isolated and identified as 1 (5-hydroxy-2-methyl-1,4-naphthoquinone / plumbagin) and 2 (3,3'-biplumbagin). Compounds 1 and 2 showed the highest antibacterial and antifungal activities compared with other extracts tested. The MIC and MBC values for the most active compound 1 were in the range of 0.001 - 0.09 and 0.004 - 0.21 mg mL⁻¹, while MIC and MFC were determined as 0.001 - 0.11 and 0.002 - 0.19 mg mL⁻¹, respectively. The isolated compounds and leaf extracts showed also equal or higher antimicrobial activities compared with antibiotics/commercial reagents which indicate that the plant might be useful for drug development. This is the first report on the antibacterial and antifungal activities, as well as the antioxidant properties of the tested plant parts and isolated compounds.

Topics: Anti-Bacterial Agents; Anti-Infective Agents; Antifungal Agents; Antioxidants; Bacteria; Biphenyl Compounds; Fungi; Microbial Sensitivity Tests; Naphthoquinones; Picrates; Plant Extracts; Plant Leaves; Plumbaginaceae; Tannins

Diospyros bipindensis (Gürke) stem bark is used in Cameroon by Baka Pygmies for the treatment of respiratory disorders.. To assess the anti-inflammatory, antibacterial and antioxidant properties of constituents from the bark extracts through bioassay-guided fractionation.. The anti-inflammatory activity of extracts, fractions and pure compounds was assessed through the inhibition of the pro-inflammatory mediator nuclear factor-kappa B (NF-κB) transcriptional activity and nitric oxide (NO) production. DPPH, ABTS and ORAC assays were used for determining the antioxidant properties. The activity against Streptococcus pneumoniae, Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Klebsiella pneumoniae, was evaluated on the basis of the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) by the macrodilution method.. The water extract showed antimicrobial activity against S. pneumoniae (MIC: 300 μg/ml) and S. pyogenes (MIC: 300 μg/ml). The dichloromethane extract efficiently inhibited NF-κB transcriptional activity and NO production and exhibited significant antioxidant activity in the ORAC assay. An interesting activity was also found against S. pneumoniae (MIC: 200 μg/ml), S. aureus (MIC: 400 μg/ml) and S. pyogenes (MIC: 200 μg/ml). The phytochemical investigation of the dichloromethane extract afforded plumbagin, canaliculatin, ismailin, betulinic acid and 4-hydroxy-5-methyl-coumarin as the main constituents. Plumbagin and ismailin were found to be responsible for the main biological activities observed.. These results may provide a rational support for the traditional use of Diospyros bipindensis stem bark in the treatment of respiratory disorders, since the anti-inflammatory, antimicrobial and antioxidant compounds isolated from the dichloromethane extract were also present in the traditional water extract.

Topics: Animals; Anti-Bacterial Agents; Anti-Inflammatory Agents; Antioxidants; Bacteria; Betulinic Acid; Biphenyl Compounds; Cell Line; Diospyros; HEK293 Cells; Humans; Mice; Microbial Sensitivity Tests; Naphthoquinones; NF-kappa B; Nitric Oxide; Pentacyclic Triterpenes; Picrates; Plant Bark; Plant Extracts; Triterpenes; Tumor Necrosis Factor-alpha