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Investigation of the leaves of Bauhinia thonningii Schum led to the isolation and identification of a new flavonol derivative, 6-C-methylquercetin-3,4'-dimethyl ether (1) together with eleven known compounds (2–13), with two of them (10 and 11) obtained as a mixture. Their structures were established by extensive spectroscopic analyses. Antibacterial activity of compound 1 as well as the reference antibiotic, ciprofloxacin was tested on Gram-negative multidrug-resistant bacteria overexpressing active efflux pumps, and against methicillin-resistant strains of Staphylococcus aureus (MRSA). Samples were tested alone and in combination with an efflux pump inhibitor (EPI), phenylalanine-arginine-β-naphthylamide (PAßN). Results show that when compound 1 was tested alone, its inhibitory effects were obtained on 7/10 tested bacteria with the highest MIC value of 128 µg/mL whilst in the presence of EPI, this activity significantly increase in all the 10 bacteria. An interesting antibacterial activity was obtained with compound 1 against Klebsiella pneumoniae ATCC11296 (MIC of 4 µg/mL), KP55 and Staphylococcus aureus MRSA6 in the presence of the PaßN. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the methanol extract of the stem bark of Chrysophyllum lacourtianum led to the isolation and characterization of one new secondary metabolite, lacourtianal (1), together with eight known compounds. Compounds 2; 3; 5; 6; 7 and 9 were reported for the first time from Chrysophyllum genus. The structures of compounds 1–9 were elucidated on the basis of 1 D and 2 D NMR spectroscopic and mass spectrometric data as well as comparison with the literature. The antibacterial activity of the methanol extract, fractions and compounds 1–9 were evaluated against bacterial strains. The methanol extract exhibited moderate activity against Staphylococcus aureus NR4674 with MIC values of 500 µg/mL. The n-hexane fraction showed moderate activity against Staphylococcus aureus (ATCC 43300 and ATCC 25923) with MIC values of 125 µg/mL and ursolic acid (5) exhibited strong activity against Enterobacter aerogenes CPC and Escherichia coli ATCC 25322 with MIC values of 7.8 and 3.9 µg/mL respectively. [ABSTRACT FROM AUTHOR]

A new α-pyrone, asperpyrone (1) and two known compounds, stigmasterol (2) and 7-hydroxy-3-(2,3-dihydroxybutyl)-1(3H)-Isobenzofuranone (3) were isolated from the solid rice culture of the endophytic fungus Aspergillus sp., an endophytic fungus isolated from the fresh inner tissue of the barks of Garicinia smeathmannii. Their structures were determined by extensive spectral analysis including 1 D and 2 D NMR, HRESIMS and single-crystal X-ray crystallographic analysis. Asperpyrone (1) was tested against an axenic culture of Entamoeba moshkovskii, but did not exhibit any significant amoebicidal activity. [ABSTRACT FROM AUTHOR]

Twenty-two compounds were isolated from the fruit of Albizia lebbeck including one unprecedented, rare amino acid-derived zwitterionic and one new flavone derivative. The isolation was performed on repeated column chromatography over silica gel and their structures were determined by 1D-, 2D-NMR and HR-ESI-MS spectra together with reported data in the literature. The chemophenetic significance is also discussed. Some isolated compounds were reported for the first time to be found in the species. Additionally, compound 2 showed antibacterial activity and compounds 1 and 2 revealed moderate cytotoxic activity against the Raw 264.7 cancer cell line with IC50 values of 37.19 µM and 29.36 µM, respectively. Furthermore, a proposed biosynthetic pathway of compound 1 is described. [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]

Objective. The present study investigated the effect of the leaves extracts and fractions of Plectranthus glandulosus on the inhibition of pancreatic lipase, cholesterol esterase, adipocytes lipid uptake, and antithrombotic activity which may be important in atherosclerosis development. Methods. Aqueous, ethanolic, and hydroethanolic extracts of Plactranthus glandulosus were prepared by maceration. The hydroethanolic extract was fractionated into n-hexane, ethylacetate, and n-butanol fractions and their inhibition of pancreatic lipase, cholesterol esterase, adipocytes lipid uptake, and antithrombotic activities measured. Liquid chromatography-high resolution mass spectrometry (LC-HRMS) analysis was carried out to determine phytochemical constituents present in the extracts. Results. The standard orlistat exhibited a higher inhibitory activity on pancreatic lipase and cholesterol esterase (16.31 μg/mL and 15.75 μg/mL, respectively) compared to ethyl acetate fraction (IC50, 17.70 μg/mL and IC50, 24.8 μg/mL, respectively). Among crude extract, hydroethanolic extract showed a better inhibition against pancreatic lipase (IC50, 21.06 μg/mL) and cholesterol esterase (IC50, 25.14 μg/mL) though not comparable to the effect of orlistat. The best lipid uptake inhibition was observed in the hydroethanolic extract (IC50, 45.42 μg/mL) followed by the ethyl acetate fraction (IC50, 47.77 μg/mL). A better antithrombolytic activity was exhibited by the ethyl acetate fraction at all concentrations (50-800 μ/mL), while hydroethanolic extract exhibited the best activity among crude extract. However, these were not comparable to the standard aspirin. The LC-HRMS analysis revealed the presence of 7-O-methyl luteolin 5-O-β-D-glucopyranoside, chrysoeriol 5-O-β-D-glucopyranoside, 5,7-dihydroxy-3,2 ′ ,4 ′ -trimethoxyflavone, and plectranmicin as major compounds in both hydroethanolic extract and ethyl acetate fraction. Conclusion. Thus, our finding supports the traditional use of this plant, which might provide a potential source for future antiatherosclerotic drug discovery. [ABSTRACT FROM AUTHOR]

Stem barks of Boswellia dalzielii are used traditionally for the treatment of various bacterial infections. A bioassay guided fractionation of the MeOH-CH2Cl2 (1/1, v/v) stem barks extract led to the isolation of fourteen compounds 1–14, identified based on spectroscopic data. Dalzienoside (1) is reported here for the first time. The broth microdilution method was used to evaluate the antibacterial activity of the crude extract, fractions and compounds against six bacterial strains. The crude extract exhibited moderate antibacterial activity with MIC of 250 μL/ml; two fractions showed significant activities with MICs ranging from 7.8 to 125 μg/ml, while α-boswellic acid (2), β-boswellic acid (3), acetyl-11-keto-β-boswellic acid (4) from these fractions exhibited strong activities with MIC value of 3.125 µg/mL against Staphylococcus aureus, Salmonella typhi, Enterobacter cloacae, Streptococcus pneumonia and Pseudomonia aeruginosa. This study gives insight into the antibacterial constituents of the stem bark of B. dalzielii and justifies its use in ethnomedicine. [ABSTRACT FROM AUTHOR]

One new indole alkaloid derivative, 5,6-dioxo-11-hydroxy voacangine (1) together with four known compounds (2-5), were isolated from the fruits of Tabernaemontana inconspicua Stapf (Apocynaceae). Their structures were determined using 1D and 2D NMR, HRESI-MS, and a comparison with the literature. The new compound was found to be cytotoxic on human breast cancer MDA-MB 231 cells with IC50 values of 3.35 µM and 2.19 µM after 24 and 48 hours, respectively. [ABSTRACT FROM AUTHOR]

• Isolation of 4 new compounds from the fruits of Gambeya lacourtiana (Sapotaceae). • First report of cerebrosides and ceramide in the genus Gambeya. • Moderate antibacterial activity of lacourtianoside II. • MS/MS fragmentation of compounds 1, 2 and 4 Phytochemical investigation of the fruits of Gambeya lacourtiana led to the isolation of four new compounds, lacourtianol (1) , lacourtianoside I (2) , lacourtianoside II (3) and lacourtianamide (4) together with six known compounds: 3- O -acetylbetulin (5) , 3- O -acetylerythrodiol (6) , β -amyrincaproate (7) , lupeolhexanoate (8) , erythrodiol 3- O -palmitate (9) , and D -mannitol (10). The structures of 1 - 10 were elucidated on the basis of 1D and 2D NMR spectroscopic data, mass spectrometry and by comparison of spectroscopic data with those from the literature. Compounds 1 - 10 were evaluated for their antibacterial activity. Lacourtianoside II (3) exhibited moderate activity against Salmonella typhi CHU, Staphylococcus aureus (ATCC 43300 and ATCC 25923) and Enterobacter cloacae k2 with the same MIC value of 22.3 μM. [ABSTRACT FROM AUTHOR]

A new lactam, oligoamide (1), along with three known compounds (2–4), stigmasterol-3-O-β-D-glucopyranoside (2), formononetin (3) and (-)-pinitol (4) were isolated from the CH2Cl2/CH3OH (1:1) extract of the leaves of Angylocalyx oligophyllus by chromatographic separation. Their structures were elucidated on the basis of spectroscopic analysis (UV, IR, MS, 1D, and 2D NMR). Compound 1 was found to have weak antioxidant and urease inhibitory potential. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Plants of the genus Tabernaemontana mainly contain monoterpenoid indole alkaloids as well as triterpenoids. • This article reports the isolation of two new monoterpenoid indole alkaloids. • The compounds were isolated using usual chromatographic method and their structures elucidated using 1D and 2D NMR. Abstract Two new indole alkaloid derivatives, 5,6-dioxo-11-methoxy voacangine (1) and (-)-apparicin-21-one (2), together with four known compounds, voacangine (3), ursolic acid (4), 3-methoxyursolic acid (5) and asiatic acid (6) were isolated from the fruits of Tabernaemontana contorta Stapf (Apocynaceae). Their structures were determined using 1D and 2D NMR and HRESI-MS measurements. The new indole alkaloids were tested on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells to determine their inhibitory effect on nitric oxide (NO) production, but did not have any significant inhibitory activity. Compound (1) slightly increased the proliferation of RAW 264.7 cells in relation with the increased level of NO released by these cells. [ABSTRACT FROM AUTHOR]

Lambertellin ( 1 ) and ergosta-5,7,22-trien-3-ol ( 2 ) were isolated from the solid rice fermentation of the plant pathogenic fungus Pycnoporus sanguineus MUCL 51321. Their structures were elucidated using comprehensive spectroscopic methods. The isolated compounds were tested on lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. Lambertellin ( 1 ) exhibited promising inhibitory activity against nitric oxide (NO) production with IC 50 value of 3.19 µM, and it significantly inhibited the expression of inducible NO synthase (iNOS) and cyclooxygenase 2 (COX-2). Lambertellin ( 1 ) also decreased the expression of pro-inflammatory cytokines IL-6 and IL-1β. The study of the mechanistic pathways revealed that lambertellin ( 1 ) exerts its anti-inflammatory effect in LPS-stimulated RAW 264.7 macrophage cells by modulating the activation of the mitogen activated protein kinase (MAPK) and nuclear factor κB (NF-κB) signaling pathways. Therefore, lambertellin ( 1 ) could be a promising lead compound for the development of new anti-inflammatory drugs. [ABSTRACT FROM AUTHOR]

Chemical investigation of Aspergillus japonicus CAM231, isolated from the leaf of Garcina preussii collected in Cameroon, yielded two new compounds; one pyrone derivative, hydroxy neovasinin (1) and one phenol derivative, asperolan (2), together with two known compounds neovasifurarone B (3) and variecolin (4). The structures of the two new compounds were established using intensive NMR spectroscopy and HRMS spectra in comparison with data found in literature. The structure of compound 1 was confirmed by single-crystal X-ray crystallographic analysis in combination with NOESY experiment. The new compounds were screened for their cytotoxic and antibacterial properties; however, the tested compounds displayed no significant activities. [ABSTRACT FROM AUTHOR]

Background: The continuous emergence of multidrug-resistant (MDR) bacteria drastically reduced the efficacy of our antibiotic armory and consequently, increased the frequency of therapeutic failure. The search for bioactive constituents from endophytic fungi against MDR bacteria became a necessity for alternative and promising strategies, and for the development of novel therapeutic solutions. We report here the isolation and structure elucidation of antibacterial and cytotoxic compounds from Phomopsis sp., an endophytic fungus associated with Garcinia kola nuts. Methods: The fungus Phomopsis sp. was isolated from the nut of Garcinia kola. The crude extract was prepared from mycelium of Phomopsis sp. by maceration in ethyl acetate and sequentially fractionated by column chromatography. The structures of isolated compounds were elucidated on the basis of spectral studies and comparison with published data. The isolated compounds were evaluated for their antibacterial and anticancer properties by broth microdilution and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide methods respectively. The samples were also tested spectrophotometrically for their hemolytic properties against human red blood cells. Results: The fractionation of the crude extract afforded three known cytochalasins including 18-metoxycytochalasin J (1), cytochalasins H (2) and J (3) together with alternariol (4). The cytochalasin compounds showed different degrees of antibacterial activities against the tested bacterial pathogens. Shigella flexneri was the most sensitive microorganism while Vibrio cholerae SG24 and Vibrio cholerae PC2 were the most resistant. Ampicillin did not show any antibacterial activity against Vibrio cholerae NB2, Vibrio cholerae PC2 and Shigella flexneri at concentrations up to 512 µg/mL, but interestingly, these multi-drug resistant bacterial strains were sensitive to the cytochalasin metabolites. These compounds also showed significant cytotoxic properties against human cancer cells (LC50 = 3.66-35.69 µg/mL) with low toxicity to normal non-cancer cells. Conclusion: The three cytochalasin compounds isolated from the Phomopsis sp. crude extract could be a clinically useful alternative for the treatment of cervical cancer and severe infections caused by MDR Shigella and Vibrio cholerae. [ABSTRACT FROM AUTHOR]

Three new polyketides named penialidins A–C ( 1 – 3 ), along with one known compound, citromycetin ( 4 ), were isolated from an endophytic fungus, Penicillium sp., harbored in the leaves of the Cameroonian medicinal plant Garcinia nobilis . Their structures were elucidated by means of spectroscopic and spectrometric methods (NMR and HRMS n ). The antibacterial efficacies of the new compounds ( 1 – 3 ) were tested against the clinically-important risk group 2 (RG2) bacterial strains of Staphylococcus aureus and Escherichia coli . The ecologically imposing strains of E. coli (RG1), Bacillus subtilis and Acinetobacter sp. BD4 were also included in the assay. Compound 3 exhibited pronounced activity against the clinically-relevant S. aureus as well as against B. subtilis comparable to that of the reference standard (streptomycin). Compound 2 was also highly-active against S. aureus . By comparing the structures of the three new compounds ( 1 – 3 ), it was revealed that altering the substitutions at C-10 and C-2 can significantly increase the antibacterial activity of 1 . [ABSTRACT FROM AUTHOR]

The phytochemical study was done on the leaves of Gambeya lacourtiana. This plant has been used in traditional medicine to treat of different ailments such as uterine heamorrhage, metritis and other vaginal infections. Chromatographic fractionation and purification on the leaves crude extract afforded lupeol acetate (1), lupenone (2), lupeol (3), taraxerol (4) stigmasterol (5), erythrodiol (6), chamaedrydiol (7), methyl pheophorbide-a (8), corosolic acid (9), tormentic acid (10), epicatechin (11) and 22-dihydrospinasterol 3- O - β - D -glucopyranoside (12). The structures of compounds 1 – 12 were elucidated on the basis of 1D and 2D NMR, mass spectrometric and the spectroscopic data as well as comparison with the literature. Compounds 4 , 7 – 10 and 12 were isolated for the first time from Gambeya genus. Crude extract, fractions and compounds 6–12 were evaluated for their antibacterial activity. Methyl pheophorbide-a (8) demonstrated moderate activity against Salmonella typhi CPC with MIC values of 62.5 μg/mL. The chemophenetic significance of these compounds is also discussed. [Display omitted] • Isolation of 12 compounds from the leaves of Gambeya lacourtiana (Sapotaceae). • First report of a chlorophyll type skeleton in the genus Gambeya. • First antibacterial report of the leaves of Gambeya lacourtiana. [ABSTRACT FROM AUTHOR]

The phytochemical investigation of the CH 2 Cl 2 /MeOH (1:1) crude extract from the stems of Angylocalyx oligophyllus (Baker) led to the isolation and characterization of 2 α ,3 α ,24-trihydroxyolean-12-en-28-oïc acid (1), 2 α ,3 α ,24-trihydroxyolean-11,13(18)-dien-28-oic acid (2) betulinic acid (3), ursolic acid (4), lupeol (5), lupenone (6), 8- O -methylretusin (7), 3-methoxydainzein (8), afromosin (9), β -sitosterol (10), β -sitosterol 3- O - β - D -glucopyranoside (11), and α - D -glucopyranosyl- O -(1 → 2)- β - D -fructofuranoside (12). The structures of compounds 1 – 12 were elucidated on the basis of 1D and 2D NMR, mass spectrometry and the spectroscopic data as well as comparison with the literature. All the isolated compounds (1 – 12) were reported for the first time from the genus Angylocalyx. Compounds 1 and 2 are reported from the Fabaceae family for the first time. The chemophenetic significance of these compounds is also discussed. The stems of Angylocalyx oligophyllus (Baker) Baker f. and isolated compounds. [Display omitted] • Isolation of twelve compounds from the stem of Angylocalyx oligophyllus Baker. (Fabaceae). • First report in these compounds from the genus Angylocalyx. • First report of two compounds from the Fabaceae family. [ABSTRACT FROM AUTHOR]

The chemical investigation of the CH 2 Cl 2 /MeOH (1:1) extract of the leaves of Rothmannia hispida (K. Schum.) Fagerl. (Rubiaceae) led to the isolation of a new ceramide rothmanniamide (1) and a naturally isolated alkyl cinnamate derivative n -heptadecyl-4-hydroxy- trans -cinnamate (2), along with fifteen known compounds including lupeol palmitate (3), lupeol (4), a mixture of uvaol (5) and erythrodiol (6), ursolic acid (7), 30- nor -2 α, 3 β -dihydroxyurs-12-ene (8), hederagenin (9), stigmast-22-en-3-ol (10), a mixture of β -sitosterol (11) and stigmasterol (12), stigmast-4,22-dien-3-ol (13), stigmasterol 3- O - β -D-glucoside (14), triacontan-1-ol (15), kaempferol 3- O - β -D-glucopyranoside (16) and D-mannitol (17). Their structures were elucidated with the help of MS and NMR data. Compounds 8 , 10 and 15 were isolated for the first time from the Rubiaceae family. The crude extract and the isolates were assessed in vitro for their antileishmanial activity against Leishmania donovani 1 S (MHOM/SD/62/1 S) promastigotes and cytotoxicity on RAW 264.7 macrophage cells. Compounds 7 and 8 exhibited a highly potent antileishmanial activity with IC 50 values of 0.88 and 1.75 μg/mL, respectively, with good selectivity indexes (SI > 57). The chemophenetic significance of these compounds is also discussed. Image 1 • New secondary metabolites in Rothmannia hispida (K. Schum.) Fagerl. (Rubiaceae). • Three compounds were isolated for the first time from the Rubiaceae family. • Antileishmanial compounds from R. hispida. • The chemophenetic significance of the isolated compounds was discussed. [ABSTRACT FROM AUTHOR]