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In the search of cytotoxic dihydrochalcones, this investigation led to the isolation of seven compounds (1-7) from Eriosema glomeratum and the preparation of eight derivatives (8-15). The cytotoxicity of samples was evaluated against lung (A549), breast (MCF-7), and cervical (HeLa) human cancer cells. The CH2Cl2/MeOH extract of the aerial part had strong cytotoxicity against all cells [IC50 11.2 (MCF-7), 8.4 (HeLa) and 13.1 (A549) μg/mL]. A strong activity was also displayed by the n-hexane fraction on MCF-7 (IC50 11.2 μg/mL). The precursor 3 and the derivative 8 were specifically found as strong cytotoxic agents toward MCF-7 (7.6 μM) and HeLa (3.1 μM), respectively and were more effective than the positive control. Derivatives 8 (3.1 μM) and 9 (21.3 μM) against HeLa were most potent than their precursor 3 (23.7 μM). This is the first preparation of 8-14 as well as the cytotoxicity of 3, 4, 8-15, fractions, and extract. [ABSTRACT FROM AUTHOR]

Two new fatty acid esters of triterpenoids (1–2) together with eleven known compounds (3–13) were obtained after investigation of the CH2Cl2-MeOH (1:1) crude extract from the leaves of Schefflera barteri Harms. All these compounds (1–13) were isolated for the first time from this plant among which compounds 3, 4, 6 and 9–13 were also isolated from the genus Schefflera for the first time. The structures of the isolated compounds were elucidated by analyses of their spectroscopic data (1D and 2D NMR, and MS). The antibacterial and cytotoxic activities of crude extracts, fractions and compounds (1, 2, 5, 6, 8 and 9) were investigated against both Gram-negative and Gram-positive bacteria strains as well as on human cervix carcinoma and colon adenocarcinoma cancer cell lines, respectively. They showed weak to significant activity towards the strains and malignant cells used. [ABSTRACT FROM AUTHOR]

A new alkylbenzoquinone named embeliquinone (1) together with five known compounds, lupeol (2), 3-O-[6′-O-palmitoyl-β-d-glucosyl]-spinasta-7,22(23)-diene (3), quercetin (4), (2S,3S,4R,8E)-2-[(2′R)-2′-hydroxy-heneicosanoylamino]-heneicosane-1,3,4-triol-8-ene (5), and β-sitosterol-3-O-β-d-glucopyranoside (6) were isolated from the MeOH leaf extract of Embelia rowlandii by using repeated open column chromatography techniques. The structure of the new compound was characterized by analyses of 1D- and 2D-NMR, and MS data. Embeliquinone (1) had moderate anti-cell proliferation activity against A549 cell line with the IC50 value of 21.8 μM. In addition, 1 exhibited weak antibacterial activities against Klebsiella pneumoniae and Staphylococcus aureus with an MIC value of 206.0 μM in both cases. [ABSTRACT FROM AUTHOR]

Background: Antimicrobial resistance is a serious threat against humankind and the search for new therapeutics is needed. This study aims to investigate the antimicrobial and antioxidant activities of ethanol extracts and compounds isolated from Dissotis senegambiensis and Amphiblemma monticola, two Cameroonian Melastomataceae species traditionally used for the treatment of fever, malaria and infectious diseases. Methods: The plant extracts were prepared by maceration in ethanol. Standard chromatographic and spectroscopic methods were used to isolate and identify fourteen compounds from the two plant species [1–6 (from D. senegambiensis), 3, 4 and 7–14 (from A. monticola)]. A two-fold serial micro-dilution method was used to determine the minimum inhibitory concentration (MIC) against four bacterial strains including two resistant bacterial strains, methicillin resistant S. aureus (MRSA3) and methicillin resistant S. aureus (MRSA4) and three yeast strains. Results: The fractionation of EtOH extracts afforded fourteen compounds belonging to triterpenoid and phenolic derivatives. The ethanol extracts, compounds 3, 5–8, 10 and the mixture of 10 + 12 were active against all the tested bacterial and fungal species. Compound 7 (MIC = 16–32 μg/mL) and 10 (MIC = 8–16 μg/mL) displayed the largest antibacterial and antifungal activities, respectively. Compounds 7, 10 and the mixture of 10 + 12 showed prominent antibacterial activity against methicillin- resistant S. aureus (MRSA) which is in some cases equal to that of ciprofloxacin used as reference antibacterial drug. Compound 8 also showed high radical-scavenging activities and ferric reducing power when compared with vitamin C and butylated hydroxytoluene used as reference antioxidants. The tested samples were non-toxic to normal cells highlighting their good selectivity. Conclusions: The result of this investigation reveals the potential of D. senegambiensis and A. monticola as well as the most active compounds in the search for new antimicrobial and antioxidant agents. So, further investigations are needed. [ABSTRACT FROM AUTHOR]

A trans cinnamic anhydride (1) isolated for the first time from a natural source, along with the known compounds: ferrulic acid (2), (E) p-hydroxy cinnamic acid (3), clovanediol (4), squalene (5), and α-bisabolene (6) were isolated from the stem bark of Cinnamomum zeylanicum. Their structures were elucidated by interpretation of NMR and MS data, and by comparison of these data with those reported in the literature. Their inhibitory properties were evaluated against Plasmodium falciparum enoyl-ACP reductase (PfENR) enzyme. Compounds 1, 5 and 6 showed moderate inhibitory activity against P. falciparum enoyl-ACP reductase (PfENR) enzyme. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Pittosporum mannii (Pittosporaceae) is used in Africa traditional medicine to treat various ailments including pain and inflammation. Aim of the study The present work was undertaken to evaluate the antinociceptive effects of the aqueous (AEPM) and methanol (MEPM) extracts from the leaves of Pittosporum mannii . Methods High performance liquid chromatography coupled with mass spectrometry (LCMS) was used for the phytochemical analysis of AEPM prepared as decoction and MEPM prepared as cold maceration. The in vitro cytotoxicity of AEPM and MEPM were evaluated on Artemia salina larvae. AEPM and MEPM antinociceptive effects were evaluated at the doses of 35, 75, 150 and 300 mg/kg given orally, against pain induced by acetic acid, formalin, hot plate, capsaicin and glutamate. The rota rod test was also performed at the same doses. To determine the mechanism of action of these extracts, their antinociceptive effects were tested in animals pretreated with yohimbine (α 2 -adrenergic antagonist), atropine (muscarinic antagonist) or naloxone (an opioids antagonist). Result The LCMS analysis showed that both extracts contain pittovidoside and 1- O -rhamnopyranosyl-23-acetoxyimberbic acid 29-methyl ester, the aqueous extract being more concentrated. Oral administration of both extracts significantly reduced pain symptoms induced by acetic acid, formalin, capsaicin, glutamate and hot plate. The antinociceptive effect of AEPM was significantly inhibited by yohimbine, atropine and naloxone while these inhibitors tend to potentiate the activity of MEPM. Both extracts have no effect on Rota rod test. AEPM and MEPM showed respective LC 50 of 2.44 and 0.70 mg/ml on Artemia larvae and were therefore, considered non-toxic. Conclusion These results indicate that AEPM and MEPM possesses analgesic effects with different mechanism of action. Although effects of both extracts may involve TRPV1 receptors and glutamatergic pathway, AEPM may in addition, interact with alpha-adrenergic, muscarinic and opioidergic pathways that are not involve in the effects of MEPM. [ABSTRACT FROM AUTHOR]

Abstract Three new lignoids, premnan A (1), premnan B (2), and tauntangyiol C (3), were isolated from Premna serratifolia wood, a traditional cosmetic plant in Myanmar, together with a new lignoid, premnan C (4) assumed to be an artifact, one natural new lignoid (5), and three known lignoids (6 – 8). The structures of the new compounds 1 – 4 were elucidated based on 1D and 2D NMR, IR spectroscopy, and HRESIMS. The absolute configurations of 1 – 4 were also determined by optical rotation, circular dichroism (CD) data analyses, and comparisons with the reported literature. All isolated compounds were tested for their melanogenesis activities against the B16-F10 mouse melanoma cell line. Compounds 1 and 4 showed melanogenesis enhancing activities of 31% and 50%, respectively, at a 50 μM concentration. Compounds 2 , 3 , and 6 increased melanin production by 67%, 30%, and 45%, respectively, at a 100 μM concentration, without any cytotoxicity. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

Two new fatty acid esters of triterpenoids ( 1 - 2 ) together with eleven known compounds ( 3 - 13 ) were obtained after investigation of the CH 2 Cl 2 -MeOH (1:1) crude extract from the leaves of Schefflera barteri Harms. All these compounds ( 1 - 13 ) were isolated for the first time from this plant among which compounds 3 , 4 , 6 and 9 - 13 were also isolated from the genus Schefflera for the first time. The structures of the isolated compounds were elucidated by analyses of their spectroscopic data (1D and 2D NMR, and MS). The antibacterial and cytotoxic activities of crude extracts, fractions and compounds ( 1 , 2 , 5 , 6 , 8 and 9 ) were investigated against both Gram-negative and Gram-positive bacteria strains as well as on human cervix carcinoma and colon adenocarcinoma cancer cell lines, respectively. They showed weak to significant activity towards the strains and malignant cells used.