Benjaminamide: A new ceramide and other compounds from the twigs of Ficus benjamina (Moraceae)

Chemical constituents from Ficus sur Forssk (Moraceae)

Phytochemical investigation of the aerial roots of Ficus sur, a Cameroonian medicinal plant, resulted in a previously undescribed cerebroside, suroside (1), in addition to its aglycon congener suramide (2). Moreover, six known natural products including alpinumisoflavone (3), wighteone metabolite (4), oleanolic acid (5), β-sitosterol (6), β-sitosterol-3-O-β-D-glucopyranoside (7), and epi-ѱ-taraxastanolone (8) were identified. The structures of the previously undescribed compounds were determined by analysis of 1D and 2D-NMR (One and two dimensional nuclear magnetic resonance), mass spectrometry, chemical conversion, and by comparison of these data with those from the literature. Wighteone metabolite (4) exhibited a weak cytotoxic activity against the human HepG2 hepatocellular carcinoma cells with an IC50 value of 51.9 µM.

Chemical constituents of two Cameroonian medicinal plants: Sida rhombifolia L. and Sida acuta Burm. f. (Malvaceae) and their antiplasmodial activity

An extensive phytochemical investigation of the EtOH/H₂O (7:3) extracts of Sida rhombifolia L. and Sida acuta Burm. f., yielded a previously undescribed ceramide named rhombifoliamide (1) and a xylitol dimer (2), naturally isolated here for the first time, as well as the thirteen known compounds viz, oleanolic acid (3), β-amyrin glucoside (4), ursolic acid (5), β-sitosterol glucoside (6), tiliroside (7), 1,6-dihydroxyxanthone (8), a mixture of stigmasterol (9) and β-sitosterol (10), cryptolepine (11), 20-Hydroxyecdysone (12), (E)-suberenol (13), thamnosmonin (14) and xanthyletin (15). Their structures were elucidated by the analyses of their spectroscopic and spectrometric data (1 D and 2 D NMR, and HRESI-MS) and by comparison with the previously reported data. The crude extracts, fractions, and some isolated compounds were tested against chloroquine-sensitive (3D7) and chloroquine-resistant (Dd2) Plasmodium falciparum strains. All the tested samples demonstrated moderate and/or significant activities against 3D7 (IC₅₀ values: 0.18-20.11 µg/mL) and Dd2 (IC₅₀ values: 0.74-63.09 µg/mL).

A new isoquinoline and ceramide from the stem barks of Discoglypremna caloneura (Pax) Prain (Euphorbiaceae) with antiproteinase and cytotoxic activities

Two new compounds, an isoquinoline (1) and caloneuramide (2), a ceramide were isolated from the stem bark of Discoglypremna caloneura together with seven known compounds namely aurantiamide acetate (3), acetylaleuritolic acid (4), 3α-hydroxylaleuritolic acid 2α-p-hydroxybenzoate (5), mixture of stigmasterol (6) and β-sitosterol (7), mixture of 7-oxo-stigmasterol (8) and 7-oxo-β-sitosterol (9). Their structures were determined based on data from literature and spectroscopic methods. Derivatization reactions on the isoquinoline led to two new compounds, the methylated (10) and acetylated (11) derivatives. Some compounds and extracts were evaluated for their cytotoxic and antiproteinase activity. Antiproteinase effect of compounds 1, 10 and 11 exhibited IC₅₀ values of 10.77, 1.19 and 3.61 μg/mL respectively; significantly low compared to the standard drug, acetyl salicylic acid (IC₅₀ = 20.28 μg/mL). Ethyl acetate and methanol extract exhibited moderate cytotoxicity activity on Chang liver cells with CC₅₀ values of 167.90 ± 2.20 and 106.30 ± 2.03 μg/mL compared to the reference drug cucurmin (CC₅₀ = 11.05 ± 1.04 μg/mL).

Investigation of antiplasmodial efficacy of lupeol and ursolic acid isolated from Ficus benjamina leaves extract

This study emphasizes on the investigation of antiplasmodial activity of triterpenoids isolated from Ficus benjamina leaves. An unsaponified fraction of petroleum ether extract of plant leaves was subjected to silica gel column chromatography which led to the isolation of two known triterpenoids; namely ursolic acid and lupeol. These compounds were evaluated for antiplasmodial activity by schizont maturation inhibition assay using 3D7 Plasmodium strains. Both, ursolic acid and lupeol were found to exhibit significant antiplasmodial effect with an IC50 value of 18 µg/ml and 3.8 µg/ml, respectively. This study further confirms the traditional role of Ficus benjamina plant in the treatment of malaria which may be attributed to ursolic acid and lupeol.

Isolation of Terpenoids from the Stem of Ficus aurantiaca Griff and their Effects on Reactive Oxygen Species Production and Chemotactic Activity of Neutrophils

Three new triterpenoids; namely 28,28,30-trihydroxylupeol (1); 3,21,21,26-tetrahydroxy-lanostanoic acid (2) and dehydroxybetulinic acid (3) and seven known compounds; i.e., taraxerone (4); taraxerol (5); ethyl palmitate (6); herniarin (7); stigmasterol (8); ursolic acid (9) and acetyl ursolic acid (10) were isolated from the stem of Ficus aurantiaca Griff. The structures of the compounds were established by spectroscopic techniques. The compounds were evaluated for their inhibitory effects on polymorphonuclear leukocyte (PMN) chemotaxis by using the Boyden chamber technique and on human whole blood and neutrophil reactive oxygen species (ROS) production by using a luminol-based chemiluminescence assay. Among the compounds tested, compounds 1–4, 6 and 9 exhibited strong inhibition of PMN migration towards the chemoattractant N-formyl-methionyl-leucyl-phenylalanine (fMLP) with IC₅₀ values of 6.8; 2.8; 2.5; 4.1; 3.7 and 3.6 μM, respectively, comparable to that of the positive control ibuprofen (6.7 μM). Compounds 2–4, 6, 7 and 9 exhibited strong inhibition of ROS production of PMNs with IC₅₀ values of 0.9; 0.9; 1.3; 1.1; 0.5 and 0.8 μM, respectively, which were lower than that of aspirin (9.4 μM). The bioactive compounds might be potential lead molecules for the development of new immunomodulatory agents to modulate the innate immune response of phagocytes.

Novel chemical constituents with anti-inflammatory activity from the leaves of Sesbania aculeata

From the hexane and ethyl acetate extracts of the leaves of Sesbania aculeata, three novel chemical compounds were isolated and fully characterized as compound 1, (ceramide type); compound 2, (cerebroside type) and compound 3 as a triterpene acid 3-O-α-L-rhamnopyranoside along with nine known compounds (Tricontanol, Lauric acid, Palmitic acid, Heptadecanoyl-1-tridecanoic acid, β-sitosterol, stigmasterol, poriferasterol glucoside, ononitol and pinitol). The anti-inflammatory potential of all three compounds were evaluated using in vitro target based anti-inflammatory activity in LPS-stimulated macrophages. TNF-α is one of the mediators of various chronic inflammatory disorders and treatment of hexane leaf extract (HL), Ethyl acetate leaf extract (EAL) and compounds 1, 2 and 3 at a dose of 10 μg/mL showed significant (P<0.001) inhibition of TNF-α, a pro-inflammatory cytokine. IL-6 was significantly (P<0.05) inhibited by compound 1 and HL at a dose of 10 μg/mL as compared with vehicle treatment. In-vitro cell cytotoxicity study using MTT assay revealed that these compounds were non toxic to the normal cells.

Essential oil Composition of Ficus Benjamina (Moraceae)and Irvingia Barteri (Irvingiaceae)

Essential oils obtained by hydrodistillation of leaves of two Nigerian species were analyzed for their constituents by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The leaf oil of Ficus benjamina L. (Moraceae), collected during the day, contained high contents of α-pinene (13.9%), abietadiene (9.7%), cis-α-bisabolene (8.2%) and germacrene-D-4-ol (8.4%), while the night sample was dominated by germacrene-D-4-ol (31.5%), 1,10-di- epi-cubenol (8.8%) and hexahydrofarnesylacetone (8.3%). This could be a possible indication of differences in emissions of volatiles by F. benjamina during the day and night. The main compounds of Irvingia barteri Hook. f. (Irvingiaceae) were β-caryophyllene (17.0%), (E)-α-ionone (10.0%), geranial (7.6%), (E)-β-ionone (6.6%) and β-gurjunene (5.1%).

Isolation and Characterization of New Ceramides from Aerial Parts of Lepidaploa cotoneaster

Two new ceramides were isolated from the bulbs of Lepidaploa cotoneaster (Willd. ex Spreng.) H. Rob. [ Vernonia cotoneaster (Willd. ex Spreng.) Less.)], in addition to germanicol, β-sitosterol, stigmasterol, 3-β- O-β-D-glucopyranosyl-sitosterol, lupeol, lupeoyl acetate and tiliroside. The structures of the new compounds were elucidated by spectral techniques (MS, 1H NMR, 13C NMR, HSQC, HMBC, DEPT, and TOCSY) and were compared with data reported in literature, and were established as 2 S*,2′ R*,3 S*,4 R*,11 E)- N-[2′-hydroxyhenicosanoyl]-2-amino-nonadec-11-ene-1,3,4-triol (1) and (2 S*,2′ R*,3 S*,4 R*,8 E)- N-[2′-hydroxytricosanoyl]-2-amino-nonadec-8-ene-1,3,4-triol (2). To establish the structure and to locate the double bond, the methyl ester of the fatty acid and dimethyl disulfide (DMDS) derivatives were prepared for both ceramides.

Isoflavone dimers and other bioactive constituents from the figs of Ficus mucuso

Phytochemical investigation of the figs of Ficus mucuso led to the isolation of three new isoflavone dimer derivatives, mucusisoflavones A-C (1-3), together with 16 known compounds. Some of the isolates were tested in vitro for their inhibitory properties toward β-glucuronidase and Plasmodium falciparum enoyl-ACP reductase (PfENR) enzymes. Compound 1 (IC₅₀) 0.68 μM) showed inhibitory activity on β-glucuronidase enzyme, while 3 (IC₅₀) 7.69 μM) exhibited a weak inhibitory activity against P. falciparum enoyl-ACP reductase (PfENR).

Antimicrobial activities of the methanol extract, fractions and compounds from Ficus polita Vahl. (Moraceae)

BACKGROUND

Many plants of the family Moraceae are used in the treatment of infectious diseases. Ficus polita Vahl., an edible plant belonging to this family is used traditionally in case of dyspepsia, infectious diseases, abdominal pains and diarrhea. The present work was designed to assess the antimicrobial activity of the methanol extract from the roots of F. polita (FPR), as well as that of its fractions (FPR1-5) and two of the eight isolated compounds, namely euphol-3-O-cinnamate (1) and (E)-3,5,4'-trihydroxy-stilbene-3,5-O-β-D-diglucopyranoside (8).

METHODS

The liquid microdilution assay was used in the determination of the minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC), against seven bacterial and one fungal species.

RESULTS

The results of the MIC determination showed that the crude extract, fractions FPR1, FPR2 and compound 8 were able to prevent the growth of the eight tested microorganisms. Other samples showed selective activity. The lowest MIC value of 64 μg/ml for the crude extract was recorded on 50% of the studied microbial species. The corresponding value for fractions of 32 μg/ml was obtained on Salmonella typhi, Escherichia coli and Candida albicans ATCC strains. The MIC values recorded with compound 8 on the resistant Pseudomonas aeruginosa PA01 strain was equal to that of chloramphenicol used as reference antibiotic.

CONCLUSION

The obtained results highlighted the interesting antimicrobial potency of F. polita as well as that of compound 8, and provided scientific basis for the traditional use of this taxon in the treatment of microbial infections.

Prenyl Coumarins from Fatoua pilosa

Six new prenylcoumarins, (+)-fatouain A (1), (-)-fatouain B (2), (+)-fatouain C (3), (-)-fatouain D (4), (+)-fatouain E (5), and (-)-fatouain F (6), along with two new bis-prenylcoumarins, (+)-fatouain G (7) and (+)-fatouain H (8), have been isolated from whole plants of Fatoua pilosa. The relative configurations of 1, 3, and 4 were confirmed by their acetonides on the basis of NOEDIF experiments, the results providing additional support for the relative configurations of 2, 5, 6, 7, and 8.

Two new ceramides from the radix of Angelica sinensis

Phytochemical investigation of the radix of Angelica sinensis has led to the isolation two new ceramides, angelicamide A (1) and B (2), along with one known ceramide, (2S, 3S, 4R, 8E)-2-[(2′R)-2′-hydroxytetracosanoyl]-8-octadecene-1,3,4-triol (3). Their structures were determined by spectroscopic methods including IR, NMR (1D and 2D NMR) and MS. This is the first report on the occurrence of ceramides in the Angelica genus.