Publications

  • [Show abstract] [Hide abstract]
    ABSTRACT: Cannabis has been around for thousands of years and has been used recreationally, medicinally, and for fiber. Over 500 compounds have been isolated from Cannabis sativa with approximately 105 being cannabinoids. Of those 105 compounds, Δ9-tetrahydrocannabinol has been determined as the primary constituent, which is also responsible for the psychoactivity associated with Cannabis. Cannabinoid receptors belong to the large superfamily of G protein-coupled receptors. Targeting the cannabinoid receptors has the potential to treat a variety of conditions such as pain, neurodegeneration, appetite, immune function, anxiety, cancer, and others. Developing in vitro bioassays to determine binding and functional activity of compounds has the ability to lead researchers to develop a safe and effective drug that may target the cannabinoid receptors. Using radioligand binding and functional bioassays, a structure–activity relationship for major and minor cannabinoids was developed.
    Medicinal Chemistry Research 09/2014; 23(9). · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The antifungal activity of twenty-two common spices were evaluated against plant pathogens using direct-bioautography coupled Colletotrichum bioassays. Turmeric, nutmeg, ginger, clove, oregano, cinnamon, anise, fennel, basil, black cumin, and black pepper showed antifungal activity against the plant pathogens Colletotrichum acutatum, C. fragariae, and C. gloesporioides. Among the active extracts, turmeric and nutmeg were the most active and were chosen for further investigation. The bioassay-guided fractionation led to the isolation of three compounds from turmeric (1-3) and three compounds from nutmeg (4-6). Their chemical structures were elucidated by spectroscopic analysis including HR-MS, 1D, and 2D NMR as curcumin (1), demethoxycurcumin (2) and bisdemethoxy-curcumin (3), erythro-(7R,8R)-Δ(8`)-4,7-dihydroxy-3,3`,5`-trimethoxy-8-O-4`-neolignan (4), erythro-(7R,8R)-Δ8`-7-acetoxy-3,4,3`,5`-tetra-methoxy-8-O-4`-neolignan (5), and 5-hydroxy-eugenol (6). The isolated compounds were subsequently evaluated using a 96-well microbioassay against plant pathogens. At 30μM, compounds 2 and 3 possessed the most antifungal activity against Phomopsis obscurans and P. viticola, respectively.
    Fitoterapia 08/2014; · 2.23 Impact Factor
  • Planta Medica 08/2014; 80:PD138. · 2.35 Impact Factor
  • Tetrahedron Letters 07/2014; · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Three natural cembranoids from the Red Sea soft coral Sarcophyton glaucum namely sarcophine (1), (+)-7alpha,8beta-dihydroxydeepoxysarcophine (2) and sarcophytolide (3) were evaluated for their potential inhibitory effects on growth of mouse melanoma B16F10 cells. Compounds (1) and (2) maximally inhibit viability of melanoma cells during 48 hr and 72 hr treatment at concentrations that show no cytotoxicity on monkey kidney CV-1 cells and also inhibit de novo DNA synthesis and PARP activity. Compound (3) produced cytotoxic effects at the same concentration range it produces its antitumor effects. These data suggest that (1) and (2), but not (3), have potential for further development as antitumor agents against melanoma.
    Natural product communications 02/2014; 9(2):151-4. · 0.96 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Cannabimimetics (commonly referred to as synthetic cannabinoids), a group of compounds encompassing a wide range of chemical structures, have been developed by scientists with the hope of achieving selectivity toward one or the other of the cannabinoid receptors CB1 and CB2. The goal was to have compounds that could possess high therapeutic activity without many side effects. However, underground laboratories have used the information generated by the scientific community to develop these compounds for illicit use as marijuana substitutes. This chapter reviews the different classes of these "synthetic cannabinoids" with particular emphasis on the methods used for their identification in the herbal products with which they are mixed and identification of their metabolites in biological specimens.
    Life sciences 01/2014; · 2.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Five hitherto unknown compounds (1–5) were isolated from the Asphodelus microcarpus. Secondary metabolites 2–4 showed potent to good activity against both methicillin resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus.
    Phytochemistry 01/2014; · 3.05 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new fatty alcohol (1) together with ten known compounds was isolated from the leaves of Terminalia arjuna Roxb. Their chemical structures were established on the basis of physical, chemical, and spectroscopic methods to be identified as (E)-3,5,7,16 tetramethylheptadeca-2-en-1-ol (1), apigenin, luteolin, vitexin, isovitexin, luteolin-3′-glucuronide, gallic acid, methyl gallate, ellagic acid, stigmasterol, and β-sitosterol-3-O-glucoside. Apigenin, vitexin, and isovitexin were isolated for the first time from this species, while luteolin-3′-glucuronide was isolated for the first time from the genus Terminalia. Compound 1 and its acetate derivative (2) showed good antileishmanial activity with IC50 values of 9.0 and 2.0 μg/mL, respectively.
    Medicinal Chemistry Research 12/2013; · 1.61 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Bioassay-guided fractionation of the EtOAc extracts of the epiphytic fungus Emericella nidulans resulted in the isolation of a mixture of two fatty acids. This mixture showed 98% binding affinity to human δ opioid receptor. These two fatty acids were identified as palmitic (PAM), 1, and linoleic acids (LNA), 2, by 1D NMR as well as by GC/MS analysis, after their methylation. We found that different ratio mixtures of 1 and 2 showed variations in selective binding activities to human δ opioid receptors. Five more fatty acids, arachidonic acid (ARA), 3, cis-4,7,10,13,16,19-docosahexanoic acid (DHA), 4, cis-5,8,11,14,17-eicosapentaenoic acid (EPA), 5, linolenic acid (ALA), 6, and γ-linolenic acid (GLA), 7, were evaluated for their binding affinity for opioid receptors. ARA, 3, displayed affinity to δ and μ human opioid receptors with 68% and 80%, respectively. GLA, 7, showed selective binding affinity to μ receptor with a value of 55%. These findings provide fascinating insight into the use of foods with high concentrations of fatty acids.
    Journal of Agricultural and Food Chemistry 10/2013; 61:10476-10480. · 3.11 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A new polyketide derivative koninginin H (1), has been isolated from the fungus Emericella nidulans, together with koninginin E (2), koninginin A (3), trichodermatide B (4), citrantifidiol (5), (4S,5R)-4-hydroxy-5-methylfuran-2-one (6), the glycerol derivatives gingerglycolipid B (7), (2S)-bis[9Z,12Z]-1-O, 2-O-dilinoleoyl-3-O-[alpha-D-galactopyranosyl-(1" --> 6') beta-D-galactopyranosyl]glycerol (8), (2S)-bis[9Z,12Z]-1-O, 2-O-dilinoleoyl-3-O-beta-D-galactopyranosylglycerol (9), the cerebroside flavuside B (10), and the known sterols beta-sitosterol glucoside and ergosta-5,7,22-trien-3-ol. Their structures were established by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC) and mass spectrometry. The antibacterial, antimalarial, antifungal and antileishmanial activities of compounds 1-10 were examined and the results indicated that compound 4 showed good antifungal activity against Cryptococcus neoformans with an IC50 value of 4.9 microg/mL.
    Natural product communications 09/2013; 8(9):1285-8. · 0.96 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The hepatoprotective activity of the ethanol extract of Astragalus kahiricus (Fabaceae) roots against ethanol-induced liver apoptosis was evaluated and it showed very promising hepatoprotective actions through different mechanisms. The extract counteracted the ethanol-induced liver enzymes leakage and glutathione depletion. In addition, it demonstrated anti-apoptotic effects against caspase-3 activation and DNA fragmentation that were confirmed by liver histopathological examination. Moreover, the phytochemical study of this extract led to the isolation of four cycloartane-type triterpenes identified as astrasieversianin II (1), astramembrannin II (2), astrasieversianin XIV (3), and cycloastragenol (4). The structures of these isolates were established by HRESI-MS and 1D and 2D NMR experiments. The antimicrobial, antimalarial, and cytotoxic activities of the isolates were further evaluated, but none of them showed any activity.
    Chinese journal of natural medicines. 07/2013; 11(4):354-361.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Bioassay-guided fractionation of a fungus Neocosmospora sp. (UM-031509) resulted in the isolation of three new resorcylic acid lactones, neocosmosin A (2), neocosmosin B (3), and neocosmosin C (4). Three known resorcylic acid lactones, monocillin IV (1), monocillin II (5), and radicicol (6), were also isolated and identified. The structures of these compounds were established on the basis of extensive 1D and 2D NMR spectroscopic analysis, mass spectrometric (ESIMS) data, and X-ray crystallography. Compounds 4-6 show good binding affinity for the human opioid receptors. These findings have important implications for evaluating the potential psychoactive effects with this class of compounds.
    Journal of Natural Products 05/2013; 76:824-828. · 3.29 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Bioassay-guided fractionation of Cladosporium cladosporioides (Fresen.) de Vries extracts led to the isolation of four compounds, including cladosporin, 1; isocladosporin, 2; 5'-hydroxyasperentin, 3; and cladosporin-8-methyl ether, 4. An additional compound, 5',6-diacetylcladosporin, 5, was synthesized by acetylation of compound 3. Compounds 1-5 were evaluated for antifungal activity against plant pathogens. Phomopsis viticola was the most sensitive fungus to the tested compounds. At 30 μM, compound 1 exhibited 92.7, 90.1, 95.4, and 79.9% growth inhibition against Colletotrichum acutatum , Colletotrichum fragariae , Colletotrichum gloeosporioides , and P. viticola, respectively. Compound 2 showed 50.4, 60.2, and 83.0% growth inhibition at 30 μM against Co. fragariae, Co. gloeosporioides, and P. viticola, respectively. Compounds 3 and 4 were isolated for the first time from Cl. cladosporioides. Moreover, the identification of essential structural features of the cladosporin nuclei has also been evaluated. These structures provide new templates for the potential treatment and management of plant diseases.
    Journal of Agricultural and Food Chemistry 05/2013; · 3.11 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Two oligosaccharides (1,2) and a stereoisomer of di-p-coumaroylquinic acid (3) were isolated from the aerial parts of Tribulus terrestris along with five known compounds (4-8). The structures of the compounds were established as O-β-d-fructofuranosyl-(2→6)-α-d-glucopyranosyl-(1→6)-β-d-fructofuranosyl-(2→6)-β-d-fructofuranosyl-(2→1)-α-d-glucopyranosyl-(6→2)-β-d-fructofuranoside (1), O-α-d-glucopyranosyl-(1→4)-α-d-glucopyranosyl-(1→4)-α-d-glucopyranosyl-(1→2)-β-d-fructofuranoside (2), 4,5-di-p-cis-coumaroylquinic acid (3) by different spectroscopic methods including 1D NMR ((1)H, (13)C and DEPT) and 2D NMR (COSY, TOCSY, HMQC and HMBC) experiments as well as ESI-MS analysis. This is the first report for the complete NMR spectral data of the known 4,5-di-p-trans-coumaroylquinic acid (4). The antioxidant activity represented as DPPH free radical scavenging activity was investigated revealing that the di-p-coumaroylquinic acid derivatives possess potent antioxidant activity so considered the major constituents contributing to the antioxidant effect of the plant.
    Phytochemistry 05/2013; · 3.05 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A chemical investigation of the Red Sea soft coral Sarcophyton glaucum led to the isolation of one new cembranoid diterpene, namely (1S,2E,4R,6E,8S,11R,12S)-8,11-epoxy-4,12-epoxy-2,6-cembradiene (2), two cembranoid diterpenes isolated from Nature for the first time, (1S,2E,4R,6E,8R,11S,12R)-8,12-epoxy-2,6-cembradiene-4,11-diol (3) and (1S,4R,13S)-cembra-2E,7E,11E-trien-4,13-diol (6) as well as three known compounds, sarcophine (1), (+)-7α,8β-dihydroxydeepoxysarcophine (4) and sarcophytolide (5). Structure elucidation was achieved using spectroscopic techniques, including 1D and 2D-NMR and HRMS. Biological activity investigations of the six isolated compounds were undertaken.
    Tetrahedron Letters 02/2013; 54(8):989–992. · 2.40 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Some Egyptian plants were screened against highly pathogenic avian influenza strain H5N1 using plaque inhibition assay in Madin-Darby canine kidney. The results indicated that the extracts of Red Sea grass Thallasodendron ciliatum possessed potent antiviral activity (100% inhibition at the concentration of 1 μg mL(- 1)). The bioactivity-guided fractionations led to the isolation of a new diglyceride ester (1) along with asebotin (2) for the first time from the plant. The two isolates showed reduction of virus titre by 67.26% and 53.81% inhibition at concentration of 1 ng mL(- 1), respectively.
    Natural product research 11/2012; · 1.01 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this study, we examined in vitro antibacterial, antifungal, antimalarial, and antileishmanial activities of secondary metabolites (1-8) isolated from the fungus Eurotium repens. All compounds showed mild to moderate antibacterial or antifungal or both activities except 7. The activity of compound 6 was the best of the group tested. The in vitro antimalarial evaluation of these compounds revealed that compounds 1-3, 5, and 6 showed antimalarial activities against both chloroquine-sensitive and chloroquine-resistant strains of Plasmodium falciparum with IC(50) values in the range of 1.1-3.0 μg/ml without showing any cytotoxicity to the mammalian cells. Compound 5 displayed the highest antimalarial activity. Antileishmanial activity against Leishmania donovani promastigotes was observed for compounds 1-6 with IC(50) values ranging from 6.2 to 23 μg/ml. Antileishmanial activity of compounds 5 and 6 (IC(50) values of 7.5 and 6.2 μg/ml, respectively) was more potent than 1-4 (IC(50) values ranging from 19-23 μg/ml). Compounds 7 and 8 did not show any antiprotozoal effect. Preliminary structure and activity relationship studies indicated that antibacterial, antifungal, antimalarial, and antileishmanial activities associated with phenol derivates (1-6) seem to be dependent on the number of double bonds in the side chain, which would be important for lead optimization in the future.
    Medicinal Chemistry Research 10/2012; 21(10):3080-3086. · 1.61 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Extracts of four species of seaweeds, Ulva lactuca L. (green), Liagora farinosa Lamouroux (red), Padina pavonia L. and Turbinaria ornata Turn (brown), were screened for their antimicrobial, and antimalarial activities, and binding affinity for human opioid receptors. Phytochemical analysis led to the isolation and identification of 10 constituents: fucosterol, stearic acid, palmitic acid, palmitoleic acid, oleic acid, myristic acid, p-hydroxybenzoic acid, beta-sitosterol, glycerol-1-olyl-3-palmotyl-2-galactoside, and glycerol-1,3-diolyl, The last two compounds displayed strong binding affinity to delta opioid receptors.
    Natural product communications 09/2012; 7(9):1209-10. · 0.96 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Gas chromatographic analysis revealed that the oil of Crinitaria tatarica was rich in sabinene (32.1%), β-pinene (8.8%), and two unknown (M+200) compounds (I) and (II) (21.4% and 3.4%). One-step multiple fractionation of the oil and separation of two unknown constituents were performed using preparative capillary gas chromatography connected to preparative fraction collector system. This combination allowed separation and recover of sufficient quantities of two unknown compounds with high purity from complex oil matrix. Separation conditions (column temperature, cooling temperature, flow rate, injection volume, cut time) were optimized to achieve the best isolation and successful collection. The target compounds were separated from the oil using a HP Innowax (Walt & Jennings Scientific, Wilmington, DE, USA) preparative capillary column in rapid one-step manner with 95.0% purity. Trapping of the isolated compounds in collector system was facilitated by cooling with liquid nitrogen. Structure determination was accomplished by spectral analysis including ultraviolet, nuclear magnetic rezonance, and high-resolution electrospray ionization mass spectrometry. Z- (I) and E-artemidin (II) were isolated for the first time from this species. Crinitaria tatarica oil and Z- (I) and E-artemidin (II) were evaluated for biological activity.
    Journal of Separation Science 01/2012; 35(5-6):650-660. · 2.59 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A phytochemical study of the aerial parts of Blepharis ciliaris (L.) B.L. Burtt. led to the isolation of one new isoflavone glycoside caffeic acid ester: genistein-7-O-(6″-O-E-caffeoyl-β-d-glucopyranoside) (4), along with seven known compounds: methyl veratrate (1), methyl vanillate (2), protocatechuic acid (3), naringenin-7-O-(3″-acetyl-6″-E-p-coumaroyl-β-d-glucopyranoside) (5), naringenin-7-O-(6″-E-p-coumaroyl-β-d-glucopyranoside) (6), apigenin-7-O-(6″-E-p-coumaroyl-β-d-glucopyranoside) (7), and acteoside (8). Their structures were established on the basis of detailed analyses of physical, chemical, and spectral data. Compounds 1, 2, 3, 6, and 8 were isolated for the first time from this plant. The antioxidant activity of the different extracts as well as for some of the isolated compounds was evaluated.
    Medicinal Chemistry Research 01/2012; · 1.61 Impact Factor

15 Following View all

95 Followers View all