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Clematis simensis is one of the most commonly used folk medicines in Ethiopia. This study was aimed to investigate the chemical constituents, antioxidant and antibacterial activities of the aerial part of Clematis simensis, and analysis of the composition of its essential oil. The phytochemical study led to the isolation of five compounds: 1-tricosanol (1), 1-hexacosanol (2), 2-deoxy-D-ribono-1,4-lactone (3), 5-hydroxylevulinic acid (4), and β-sitosterol-3-O-β-D-glucoside (5). Their chemical structures were determined by a comprehensive analysis of HRESI-MS, FT-IR, UV-Vis, and 1D/2D NMR experiments. The chemical compositions of the essential oils obtained by hydrodistillation from the aerial part of Clematis semenses were determined by GC-MS, which led to the detection of ten major compounds: (E)-2-nonen-1-ol (38.33%), 4-cyclopentene-1,3-dione (28.69%), cyclofenchene (5.65%), benzene acetaldehyde (4.74%), methyl salicylate (2.77%), salicylaldehyde (2.68%), benzaldehyde (2.60%), α-terpineol (2.10%), eucalyptol (1.21%), and 2,6-dimethylcyclohexanol (1.15%). Compound 4 showed high antioxidant activity (IC50 14.89 μg/mL) but has no antibacterial activity against both Gram-positive and Gramnegative bacterial strains. According to the antimicrobial parameters, crude extract showed very weak activity at 500 mg/mL, 250 mg/mL, and 125 mg/mL. To our knowledge, this is the first report on the isolation of secondary metabolites from Clematis simensis. [ABSTRACT FROM AUTHOR]

Myricasalicifolia A Rich (Myricaceae) is a tree growing in Central and East Africa. Traditionally, the plant is used to treat malaria, respiratory disorders, inflammations, and infections. A new compound, 3β-O-trans-caffeoylisomyricadiol (7), was isolated from MeOH : CHCl3 (2 : 1) extract of the stem bark of Myrica salicifolia along with seven known compounds, namely, myricanone (1), myricanol (2), myricanol-11-O-β-D-xylopyranoside (3), taraxerone (4), taraxerol (5), myricadiol (6), and methyl-β-D-glucopyranoside (8). This is the first report of the isolation of taraxerene-type triterpenes from this plant. The structures were determined by a comprehensive analysis of 1D/2D NMR spectroscopy, HR-MS, and by comparison with literature data. The compounds showed a wide range of DPPH scavenging activities from very weak (IC50 value = 282.61 μM) to very strong (IC50 = 13.48 μM). Antibacterial activities of the compounds were evaluated using the disk diffusion agar method, where some of the compounds showed modest antibacterial activities against S. pyogenes and S. aureus at 250 μg/mL. Compounds 2, 3, and 7 were assessed for their in silico molecular docking analysis. The lowest binding affinity for compound 7 was found to be −7.26 to −10.35 kcal/mol against PqsA protein of P. aeruginosa, pyruvate kinase (PK) enzyme of S. aureus, LuxS protein of S. pyogenes, and DNA gyrase B of E. coli, which showed better binding affinity compared to the standard drug ampicillin (−7.36 to −8.03 kcal/mol) and ciprofloxacin (−6.19 to −6.83 kcal/mol). In silico ADMET predictions revealed that compounds 3 and 8 met all the requirements for pharmacokinetic properties. [ABSTRACT FROM AUTHOR]

Chemical investigation of the endophytic fungus, Trichoderma erinaceum, isolated from healthy and asymptomatic common bean field crop, resulted in the isolation of a new alkene, (Z)-5-amino-5-(1,1,2-trihydroxybuta-1,3-dienyloxy)pentane-6,7,8,9-tetraol (1), together with five known compounds (2–6). The structures of the compounds were elucidated by analysis of their spectroscopic data including 1 D, 2 D NMR, ESI–HRMS and literature data. The organic crude extract and the compound isolated from T. erinaceum significantly (p ≤ 0.05) inhibited the mycelial growth of Pythium ultimum. [ABSTRACT FROM AUTHOR]

A new flavone, named hildeflavone (1) along with 7 other known flavonoids were isolated from the aerial parts of Tephrosia hildebrandtii Vatke. Their characterisation was based on NMR and MS data analysis. The anti-inflammatory properties of the crude extract, isolated compounds and combination of the compounds were investigated in lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs). Treatment of the LPS-stimulated PBMCs with the isolated flavonoids at a concentration of 100 µM significantly reduced the production of interleukins (IL-1β, IL-2 and IL-6), interferon-gamma (IFN-γ), granulocyte macrophage-colony stimulating factor (GM-CSF) and tumour necrosis factor-alpha (TNF-α). It was also found that the combination of a flavone and flavanones exhibited remarkable synergistic anti-inflammatory effects on the production of the cytokines. [ABSTRACT FROM AUTHOR]