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      • KCI등재
      • KCI등재

        New ursane triterpenoids from Ficus pandurata and their binding affinity for human cannabinoid and opioid receptors

        Amgad I. M. Khedr,Sabrin R. M. Ibrahim,Gamal A. Mohamed,Hany E. A. Ahmed,Amany S. Ahmad,Mahmoud A. Ramadan,Atef E. Abd El-Baky,Koji Yamada,Samir A. Ross 대한약학회 2016 Archives of Pharmacal Research Vol.39 No.7

        Phytochemical investigation of Ficus pandurataHance (Moraceae) fruits has led to the isolation of two newtriterpenoids, ficupanduratin A [1b-hydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (11) and ficupanduratin B [21ahydroxy-3b-acetoxy-11a-methoxy-urs-12-ene] (17), alongwith 20 known compounds: a-amyrin acetate (1), a-amyrin(2), 3b-acetoxy-20-taraxasten-22-one (3), 3b-acetoxy-11amethoxy-olean-12-ene (4), 3b-acetoxy-11a-methoxy-12-ursene (5), 11-oxo-a-amyrin acetate (6), 11-oxo-b-amyrinacetate (7), palmitic acid (8), stigmast-4,22-diene-3,6-dione(9), stigmast-4-ene-3,6-dione (10), stigmasterol (12), b-sitosterol(13), stigmast-22-ene-3,6-dione (14), stigmastane-3,6-dione (15), 3b,21b-dihydroxy-11a-methoxy-olean-12-ene (16), 3b-hydroxy-11a-methoxyurs-12-ene (18), 6-hydroxystigmast-4,22-diene-3-one (19), 6-hydroxystigmast-4-ene-3-one (20), 11a,21a-dihydroxy-3b-acetoxy-urs-12-ene(21), and b-sitosterol-3-O-b-D-glucopyranoside (22). Compound21 is reported for the first time from a natural source. The structures of the 20 compounds were elucidated on thebasis of IR, 1D (1H and 13C), 2D (1H–1H COSY, HSQC,HMBC and NOESY) NMR and MS spectroscopic data, inaddition to comparison with literature data. The isolatedcompounds were evaluated for their anti-microbial, antimalarial,anti-leishmanial, and cytotoxic activities. In addition,their radioligand displacement affinity on opioid andcannabinoid receptors was assessed. Compounds 4, 11, and15 exhibited good affinity towards the CB2 receptor, withdisplacement values of 69.7, 62.5 and 86.5 %, respectively. Furthermore, the binding mode of the active compounds inthe active site of the CB2 cannabinoid receptors was investigatedthrough molecular modelling.

      • KCI등재

        Murraya koenigii (L.) Sprengel seeds and pericarps in relation to their chemical profiles: new approach for multidrug resistant Acinetobacter baumannii ventilator-associated pneumonia

        El-Shiekh Riham A.,Elshimy Rana,Mandour Asmaa A.,Kassem Hanaa A. H.,Khaleel Amal E.,Alseekh Saleh,Fernie Alisdair R.,Salem Mohamed A. 한국응용생명화학회 2024 Applied Biological Chemistry (Appl Biol Chem) Vol.67 No.-

        Acinetobacter baumannii is without a doubt one of the most problematic bacteria causing hospital-acquired nosocomial infections in today’s healthcare system. To solve the high prevalence of multi-drug resistant (MDR) in A. baumannii, we investigated one of the medicinal plants traditionally used as antibacterial agent; namely Murraya koenigii (L.) Sprengel. The total methanolic extracts of seeds and pericarps were prepared and their anti-bacterial activity was assessed using the agar diffusion method and minimum inhibitory concentration (MIC) was then calculated as compared to tigecycline. Then, an in-vivo murine model was established which confirmed the promising activity of M. koenigii seeds in demonstrating anti-bacterial and anti-inflammatory actions. The histopathological study of lungs, scoring of pulmonary lesions, counting of bacterial loads after infection by multi-drug resistant A. baumannii all provided evidence to support these findings. LC–MS/MS profiling coupled to molecular networking and chemometrics detected the presence of carbazole alkaloids, and coumarins as dominate metabolites of the active seed extracts. Positively correlated metabolites to antibacterial potential were 6-(2ʹ,3ʹ-dihydroxy-3-methylbutyl)- 8-prenylumbelliferone, scopoline, and 5-methoxymurrayatin. An in-silico study was also performed on the crystal structure of MurF from A. baumannii (PDB ID: 4QF5), the studied structures of the mentioned extracts revealed good docking interaction at the active site suggestive of competition with the ATP ligand. These collective findings suggest that extracts of Murraya koenigii (L.) Sprengel seed is a novel prospective for the discovery of drug candidates against infections caused by MDR A. baumannii.

      • Determination of volatile organic compounds generated from fresh, white and red Panax ginseng (C. A. Meyer) using a direct sample injection technique

        Abd El-Aty, A. M.,Kim, In-Kyung,Kim, Mi-Ra,Lee, ChiHo,Shim, Jae-Han John Wiley Sons, Ltd. 2008 Biomedical chromatography Vol.22 No.5

        <P>Ginsenosides are regarded as the main active, non-volatile components of Panax ginseng (C. A. Meyer). However, throughout the long history of ginseng research, there has been virtually no report describing its volatile flavor compounds. A solvent-free procedure for the determination of volatile flavor compounds generated from fresh, white and red Panax ginseng (C. A. Meyer) using solvent-free solid injection (SFSI) coupled with gas chromatography-mass spectrometry (GC-MS) detection is described here. At no point in the SFSI technique were the extraction conditions optimized. Rather, the experimental variables including various sample preparations (fresh, oven-dried and freeze-dried), injector temperatures (100, 150, 200, 250 and 300°C), and preheating times (3, 5, 7, 10 and 15 min), were predicated on the experience of the authors. A total of 47 compounds were identified in various forms of ginseng. Among the compounds identified in the sample, fresh ginseng was characterized by a high proportion of 3-acetyl-1-(3,4-dimethoxyphenyl)-5-ethyl-4,5-dihydro-7,8-dimethoxy-4-methylene-3H-2,3-benzodiazepine (64.24%) and 23,24-dinor-3-oxolean-4,12-dien-28-oic acid (21.42%); 2-furanmethanol (20.26%) and 3-hydroxy-2-methyl-4H-pyran-4-one (17.95%) were detected as the major components in white ginseng while the main components of the red ginseng were found to be 1,2-benzenedicarboxylic acid dibutyl ester (16.27%) and 2-furanmethanol (13.82%). SFSI is a solvent-free, rapid and simple sample preparation technique based on direct vaporization. There is no dilution or contamination with solvent or its impurities and no loss of quickly eluted components was observed in the solvent peak. Copyright © 2008 John Wiley & Sons, Ltd.</P>

      • KCI등재

        Purification and Characterization of Anabaena flos-aquae Phenylalanine Ammonia-Lyase as a Novel Approach for Myristicin Biotransformation

        Asmaa M. Arafa,Afaf E. Abdel-Ghany,Samih I. El-Dahmy,Sahar Abdelaziz,Yassin El-Ayouty,Ashraf S. A. El-Sayed 한국미생물·생명공학회 2020 Journal of microbiology and biotechnology Vol.30 No.4

        Phenylalanine ammonia-lyase (PAL) catalyzes the reversible deamination of phenylalanine to cinnamic acid and ammonia. Algae have been considered as biofactories for PAL production, however, biochemical characterization of PAL and its potency for myristicin biotransformation into MMDA (3-methoxy-4, 5-methylenedioxyamphetamine) has not been studied yet. Thus, PAL from Anabaena flos-aquae and Spirulina platensis has been purified, comparatively characterized and its affinity to transform myristicin was assessed. The specific activity of purified PAL from S. platensis (73.9 μmol/mg/min) and A. flos-aquae (30.5 μmol/mg/min) was increased by about 2.9 and 2.4 folds by gel-filtration comparing to their corresponding crude enzymes. Under denaturing-PAGE, a single proteineous band with a molecular mass of 64 kDa appeared for A. flos-aquae and S. platensis PAL. The biochemical properties of the purified PAL from both algal isolates were determined comparatively. The optimum temperature of S. platensis and A. flos-aquae PAL for forward or reverse activity was reported at 30oC, while the optimum pH for PAL enzyme isolated from A. flos-aquae was 8.9 for forward and reverse activities, and S. platensis PAL had maximum activities at pH 8.9 and 8 for forward and reverse reactions, respectively. Luckily, the purified PALs have the affinity to hydroaminate the myristicin to MMDA successfully in one step. Furthermore, a successful method for synthesis of MMDA from myristicin in two steps was also established. Gas chromatography-mass spectrometry (GC-MS) analysis was conducted to track the product formation.

      • KCI등재

        A Protective Mechanism in Lungs of Rats Experimentally Infected with Aspergillus fumigatus

        Yehia A G. Mahmoud,Abdulaziz Yahya Al Ghamdi,Eman H. F. Abd El Zaher The Korean Society of Mycology 2011 Mycobiology Vol.39 No.1

        Aspergillus fumigatus is associated with invasive disease aspergillosis in immunocompromised individuals. The major aim of this study was to investigate the biochemical and immunological responses of male Wistar rats against A. fumigatus experimentally-induced pulmonary fungal infection. Nostril experimental exposure of male Wistar rats to a high dose of A. fumigatus freeze-dried preparation for only 24 hr resulted in a significant increase in levels of catalase, nitric oxide and lipid peroxide in lung homogenates, compared to those of the control animals. However, the oxidative status of the lungs of rats challenged with killed fungus did not change significantly, except for the stimulation in the level of lipid peroxide. IgG level was significantly elevated only in rats that received two low doses of fungus, compared to unexposed animals (p < 0.005). Examining the lung of rats exposed to A. fumigatus revealed no abnormal changes, except for pus in bronchial lumen spaces and per bronchial inflammation. Histologically, large numbers of granuloma cells were evident in the lungs of challenged rats, while no granuloma formation was evident in the lungs of rats exposed to killed fungus.

      • KCI등재후보

        THE STABILITY IN AN INCLINED LAYER OF VISCOELASTIC FLUID FLOW OF HYDROELECTRIC NATURAL CONVECTION

        A.A. El-Bary 한국산업응용수학회 2005 Journal of the Korean Society for Industrial and A Vol.9 No.2

        The problem of the onset stability in an inclined layer of dielectric viscoelastic fluid(Walter's liquid B') is studied. The analysis is made under the simultaneous action of a normal a.c. electric field and the natural convection flow due to uniformly distributed internal heat sources. The power series method used to obtain the eigen value equation which is then solved numerically to obtain the stable and unstable solutions. Numerical results are given and illustrated graphically.

      • KCI등재

        Middle Eastern Plants with Potent Cytotoxic Effect Against Lung Cancer Cells

        Jilan A. Nazeam,Soad Z. EL-Emam 한국식품영양과학회 2024 Journal of medicinal food Vol.27 No.2

        Cancer is one of the leading causes of increasing global mortality with uprising health concerns and threats. Unfortunately, conventional chemotherapy has substantial side effects, limiting its relevance and prompting a quest for safe andefficient alternatives. For thousands of years, plants have provided a rich reservoir for curing a variety of ailments, includingcancer. According to the World Health Organization, medicinal plants would be the best source of medications. However, only25% of drugs in the present pharmacopoeia are derived from plants. Hence, further research into different plants is required tobetter understand their efficacy. Twenty extracts of widely distributed Middle Eastern plants were screened for the cytotoxiceffect against lung cancer cell lines (A549). Eleven plants showed IC50 below 25 lg/mL, consequently, the bioactive extractswere further fractionated by graded precipitation using absolute ethanol. All fraction A (FA; crude polysaccharides precipitate)showed potent IC50, 0.2–5.5 lg/mL except the FA of Brassica juncea, Silybum marianum, and Phaseolus vulgaris, whereas FBfractions (filtrate) of Anastatica hierochuntica, Plantago ovate, Tussilago farfara, and Cucurbita moschata had lower efficacythan other fractions with IC50 values in the range of 0.1–7.7 lg/mL. The fractions of FA Taraxacum officinale and FB Ziziphusspina possess the most potent cytotoxic activity with IC50, 0.2 and 0.1 lg/mL, respectively. Moreover, cell cycle analysis of bothfractions revealed an arrest at G1/S-phase and activation of apoptosis rather than necrosis as the mode of cell death. Therefore, T. officinale and Z. spina fractions may pave the way to manage lung carcinoma as an alternative and complementary food regimen.

      • KCI등재

        Exchange couplings calculation in Sr2CrNO6 (N = Os, Ir) Double Perovskites: Monte Carlo simulation

        O. El Rhazouani,A. Slassi,Y. Ziat,A. Benyoussef 한국물리학회 2017 Current Applied Physics Vol.17 No.7

        Exchange couplings in Sr2CrNO6 (N ¼ Os, Ir) Double Perovskites (DPs) have been calculated numerically by using a Monte Carlo Simulation (MCS) in the frame work of Ising model by means of a relation between internal energy per site and magnetization per site. Two model parameters a and a0 have been proposed for Sr2CrOsO6 and Sr2CrIrO6, respectively. The exchange couplings have been computed by varying a and a0 through a MCS to find their values corresponding to the transition temperature 725K specific to Sr2CrOsO6 and 884K specific to Sr2CrIrO6. The exchange couplings JCr『Os ¼ 『35:201meV, JCr『Cr ¼ 5:452 meV and JOs『Os ¼ 14:873 meV have been obtained for Sr2CrOsO6, while JCr『Ir ¼ 『24:464 meV, J0 Cr『Cr ¼ 2:181 meV and JIr『Ir ¼ 16:730 meV have been obtained for Sr2CrIrO6. Magnetization and magnetic susceptibility have been investigated in both compounds. Internal energy per site has been given.

      • KCI등재

        Purification and Characterization of a New L-Methioninase from Solid Cultures of Aspergillus flavipes

        Ashraf S. A. El-Sayed 한국미생물학회 2011 The journal of microbiology Vol.49 No.1

        L-Methioninase was purified to electrophoretic homogeneity from cultures of Aspergillus flavipes using anionexchange and gel filtration chromatography by 12.1 fold compared to the crude enzyme preparation. The purified enzyme had a molecular mass of 47 kDa under denaturing conditions and an isoelectric point of 5.8 with no structural glycosyl residues. The enzyme had optimum activity at pH 7.8 and pH stability from 6.8-8.0 at 35°C. The enzyme appeared to be catalytically stable below 40°C. The enzyme activity was strongly inhibited by DL-propargylglycine, hydroxylamine, PMSF, 2-mercaptoethanol, Hg^(2+), Cu^(2+), and Fe^(2+), with slight inhibition by Triton X-100. A. flavipes L-methioninase has a higher catalytic affinity towards L-methionine (Km, 6.5 mM and Kcat, 14.1 S^(-1)) followed by a relative demethiolating activity to L-homocysteine (Km, 12 mM and Kcat, 9.3 S^(-1)). The enzyme has two absorption maxima at 280 and 420 nm,typical of other PLP-enzymes. Apo-L-methioninase has the ability to reconstitute its structural catalytic state completely upon addition of 0.15 mM PLP. L-Methioninase has neither an appreciable effect on liver function, platelet aggregation, nor hemolysis of human blood. The purified L-methioninase from solid cultures of A. flavipes displayed unique biochemical and catalytic properties over the currently applied Pseudomonad enzyme.

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