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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 root wood of Erythrina livingstoniana led to the isolation of one previously undescribed isoflavan (3S,3″R)-7-hydroxy-2′-methoxy-[3″-hydroxy-2″,2″-dimethylpyrano (3′,4′)] isoflavan 1, together with eleven known compounds 2-12. The structure of compound 1 was elucidated on the basis of extensive spectroscopic and spectrometric analyses (1 D and 2 D-NMR and APCI-HRMS), with absolute configurations established by comparison of experimental and DFT calculated ECD data. The assignment of the absolute configurations of C-3 and C-3″ of compounds 2 and 3, respectively, were reported for the first time. Compounds 1 − 4 were evaluated for their antibacterial activities in vitro against E. coli ATCC 25922 and S. aureus ATCC 25923. Compound 1 exhibited moderate antibacterial activity with MIC value of 0.063 mg/mL against the clinically relevant risk-group 2 (RG-2) bacterium S. aureus. [ABSTRACT FROM AUTHOR]

Tetrapleura tetraptera is an African medicinal spice used in traditional medicine to treat several ailments including cancer. The present study was designed to evaluate the cytotoxicity of the dichloromethane-methanol (1:1) extract of the fruits of Tetrapleura tetraptera (TTF) and its constituents: (3 R , 4 S)-3,4-dimethyloxetan-2-one (1), luteolin (2), stigmasterol (4), 3- O -[6′- O -undecanoyl- β - D -glucopyranosyl]stigmasterol (6), olean-12-en-3- β - O - D -glucopyranoside (7), 3- O - β - D -glucopyranosyl-(1 → 6)- β - D -glucopyranosylurs-12-en-28-oic acid (8), 3- O - β - D -glucopyranosyl-(1 → 3)- β - D -glucopyranosyl-27-hydroxyolean-12-ene-28-oic acid (9), methyl- O - β - D -glucopyranoside (10), β - D -fructofuranosyl-(2 → 1)- β - D -glucopyranoside (11) towards a panel of cancer cell lines including MDR phenotypes. The cellular mode of induction of apoptosis by TTF and compound 7 was further investigated. The resazurin reduction assay (RRA) was applied to determine the cytotoxicity of the studied samples. The cell cycle (PI staining), apoptosis (annexin V/PI staining), mitochondrial membrane potential (MMP; JC-1) and reactive oxygen species (ROS; H 2 DCFH-DA) were measured by flow cytometry. Column chromatography was used for the purification of TTF, whilst nuclear magnetic resonance (NMR) spectroscopic analysis was applied for structural elucidation. The botanical, TTF and the phytochemicals, 2 , 7 , 8 and 9 as well as doxorubicin exerted cytotoxicity against 9 cancer cell lines including drug-sensitive and drug resistant phenotypes. TTF, compound 7 and doxorubicin were the most active samples, and displayed IC 50 values ranging from 10.27 μg/mL (in CCRF-CEM leukemia cells) to 23.61 μg/mL (against HCT116 p53 −/− colon adenocarcinoma cells) for TTF, from 4.76 μM (against CCRF-CEM cells) to 12.92 μM (against HepG2 hepatocarcinoma cells) for compound 7 , and from 0.02 μM (against CCRF-CEM cells) to 122.96 μM (against CEM/ADR5000 cells) for doxorubicin. TTF induced apoptosis in CCRF-CEM cells through MMP alteration and increased ROS production while compound 7 induced apoptosis mediated by caspases activation, MMP alteration and increased ROS production. Tetrapleura tetraptera and some of its constituents, mostly compound 7 are good cytotoxic natural products that should be explored in depth to develop new drugs to fight cancers. The botanical, TTF and the phytochemicals, 2 , 7 , 8 and 9 had cytotoxic effect against the nine cancer cell lines tested including drug-sensitive and drug resistant phenotypes. TTF and compounds 7 had the best activities. TTF induced apoptosis in CCRF-CEM cells through MMP alteration and increased ROS production while compound 7 induced apoptosis mediated by caspases activation, MMP alteration and increased ROS production. Image 1 • The cytotoxicity of Tetrapleura tetraptera (TTF) fruit extract and compounds was evaluated. • TTF and compounds, 2 , 7 , 8 and 9 had cytotoxic effects against the 9 cancer cell lines tested. • TTF and compounds 7 had the best activities and induced apoptosis in CCRF-CEM cells. [ABSTRACT FROM AUTHOR]

Tetrapleura tetraptera fruit, used as spice in West Africa was studied chemically; five previously undescribed triterpenoid saponins 1 - 5 and four known compounds 6 - 9 were isolated from the n -Butanol fraction. The chemical structures of all nine isolates were determined by comprehensive analysis of HRMS, 1D & 2D NMR experiments and by comparison with data in the literature. All nine compounds were evaluated for antibacterial activity by the broth microdilution through the rapid p -iodonitrotetrazolium chloride (INT) colorimetric technique. The results showed that only compounds 5 (MIC = 64 µg/mL against P. aeruginosa and P. stuartii ) and 8 (MIC = 64 µg/mL against E. coli ) exhibited moderate antibacterial activity. The rest of the compounds displayed weak antibacterial activity against the tested organisms. Molecular docking studies was used to comprehend antibacterial activities.