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GC-MS Analysis (gc-m + analysis)
Selected AbstractsValidation of techniques to detect illicit heroin use in patients prescribed pharmaceutical heroin for the management of opioid dependenceADDICTION, Issue 12 2005S. Paterson ABSTRACT Background The clinical implementation and evaluation of heroin substitution programmes have been confounded by the lack of objective and validated biomarkers for illicit heroin use in patients prescribed pharmaceutical heroin. This study examined the capacity to detect illicit heroin use by gas chromatography,mass spectrometry (GC-MS) analysis of urine samples for the presence of opium impurities common to illicit, but not pharmaceutical heroin. Aims To characterize the diagnostic properties of the metabolites of noscapine and papaverine in comparison to morphine as a gold-standard marker of illicit heroin use; and to examine the relationships between the self-reported time since most recent heroin use and the detection of these opioids in urine. Design A cross-sectional study of 52 opioid-dependent patients in treatment (not prescribed heroin), who self-reported illicit heroin use within the preceding 2 weeks. Self-report data regarding recent drug use and a urine sample were collected. GC-MS analyses of urines were conducted and reported by laboratory staff blinded to self-report data. Findings The metabolites of papaverine (hydroxypapaverine and dihydroxypapeverine) were found to have high sensitivity, specificity and negative predictive values as markers for illicit heroin use compared to the ,gold-standard' morphine. Other opioids, including 6-mono-acetylmorphine (6-MAM), codeine and noscapine metabolites (e.g. meconine) were less adequate in detecting heroin use. Conclusions GC-MS detection of papaverine metabolites in urine appears to be suitable method of identifying illicit heroin use for clinical and research purposes. [source] Chemical composition of essential oil from the seeds of Nigella arvensis L. and assessment of its actimicrobial activityFLAVOUR AND FRAGRANCE JOURNAL, Issue 4 2006J. Havlik Abstract The essential oil from Nigella arvensis L. was obtained by hydrodistillation, yielding 0.42% of oil on dry weight basis. The GC and GC-MS analyses showed the presence of 69 components, predominantly monoterpenes. The major constituents were carvacrol methyl ether (26.4%), , -pinene (21.4%), n -undecane (13.2%), and , -pinene (5.7%). The oil did not exhibit antimicrobial activity when tested by microdilution method. Copyright © 2006 John Wiley & Sons, Ltd. [source] Polymer-bound alkyltriazenes for mild racemization-free esterification of amino acid and peptide derivativesJOURNAL OF PEPTIDE SCIENCE, Issue 10 2004Joachim Smerdka Abstract A novel tool for polymer-assisted solution phase (PASP) esterification of amino acid and peptide derivatives has been developed. When treated with carboxylic acids, polymer-bound alkyltriazenes react with a loss of nitrogen and transfer of the alkyl moiety to the carboxylate anion to form the corresponding alkyl esters. There are no limitations with regard to either the protecting groups or the nature of the amino acid. Furthermore no racemization occurs at the chiral centers of the amino acids as demonstrated by chiral GC-MS analyses. Alkyltriazene-resins were also applied successfully to the esterification of peptide acids and other peptidic structures, such as tripalmitoyl- S -glyceryl-cysteine (Pam3Cys). The triazene-mediated esterification reaction is exceptionally mild, and there is no need for prior activation of the carboxy groups. This method is therefore particularly suitable for the alkylation of complex peptidomimetic structures prone to racemization and for acid-sensitive structures. Copyright © 2004 European Peptide Society and John Wiley & Sons, Ltd. [source] GEOCHEMICAL CHARACTERIZATION OF A BIODEGRADED CRUDE OIL, ASSRAN FIELD, CENTRAL GULF OF SUEZJOURNAL OF PETROLEUM GEOLOGY, Issue 4 2009A. H. Hegazi A crude oil sample from the Assran field in the Central Gulf of Suez (Egypt) was analysed geochemically and characterized in terms of a variety of source and maturity dependent biomarkers. Biodegradation was indicated by increasing concentration ratios of Pr/n-C17 and Ph/n-C18. However, biodegradation was only slight as GC-MS analyses of the saturate and aromatic fractions showed that hopanes, steranes, aromatic steroids and polycyclic aromatic compounds including sulphur heterocycles remained intact. The sterane and hopane distributions showed a predominance of C27 steranes, a low diasterane index, an abundance of gammacerane, a high homohopane index and an oleanane index < 0.2. The results indicate that the Assran-10 crude oil was derived from a marine carbonate source deposited in a highly reducing saline environment with a high bacterial contribution, consistent with the Upper Cretaceous Brown Limestone or Lower Eocene Thebes Formation containing Type IIS kerogen. Maturity parameters based on changes in the stereochemistry at chirality centres in hopane and sterane nuclei, such as C30,,/(,,+,,) and C31 22S/(22S+22R) hopanes and C29,,/(,,+,,) and C29 20S/(20S+20R) steranes, together with triaromatic sterane cracking ratios, indicate that the oil sample was marginally mature. The results also suggest that biodegradation is probably due to sulphate-reducing anaerobic bacteria. [source] SOURCE ROCK EVALUATION AND GEOCHEMISTRY OF CONDENSATES AND NATURAL GASES, OFFSHORE NILE DELTA, EGYPTJOURNAL OF PETROLEUM GEOLOGY, Issue 2 2003L. M. Sharaf Geochemical analyses of mudstones from wells in the NE offshore Nile Delta suggest that the Early Miocene Qantara Formation has "good" potential to generate hydrocarbons at the studied locations. Its generating capability and oil-proneness increase northwards, towards areas where better organic-matter preservation and a greater contribution from marine source material can be expected. By contrast, the Middle Miocene Sidi Salem Formation has "poor to fair" potential to generate mixed gas and oil, while the overlying Wakar and Kafr El Sheikh Formations have "poor" capability to generate gas with minor oil. Based on pyrolysis Tmax and thermal alteration index assessments, the Wakar and Kafr El Sheikh Formations are immature in the study area. The Sidi Salem and Qantara Formations are immature in the southern part of the study area, but are within the oil window in the north, around well Temsah-4. Biomarker distributions based on GC-MS analyses of two condensate samples from the Wakar and Sidi Salem Formations indicate that hydrocarbons are derived from siliciclastic source rocks containing significant terrestrial material and limited marine organic matter. The condensates were generated during early maturation of Type III kerogen from deeper and more mature source rocks than those encountered in the drilled wells. Geochemical and isotopic data from natural gas produced from the Kafr El Sheikh Formation suggest mixed biogenic and thermogenic sources. [source] Rock hyraces: a cause of San rock art deterioration?JOURNAL OF RAMAN SPECTROSCOPY, Issue 5 2007Linda C. Prinsloo Abstract San rock art sites are found throughout southern Africa, many showing signs of deterioration. In order to conserve this invaluable heritage, a long-term multidisciplinary project has been launched to monitor the rate of their deterioration and determine the various chemical processes that are possibly contributing to the decay. This study was initiated to establish if Raman spectroscopy could contribute to this project and since rock hyrax colonies live in close proximity to many of these archaeological sites, the possible influence of their metabolic products on the deterioration process was investigated. The precipitates from the urine of rock hyraces were analysed with Raman and Fourier-transform infrared (FTIR) spectroscopy. Where the urine was in contact with the faeces, the precipitates are a mixture of vaterite (a rare polymorph of CaCO3) and the hydrated salt calcium monohydrocalcite (also rarely found in nature). On areas where this contact is at a minimum the common and stable polymorph of CaCO3, calcite, is the main component. SEM micrographs and XRD analysis support the Raman and FTIR results. XRD, FTIR and preliminary GC-MS analyses of hyraceum, the fossilised mixture of faeces and urine, identified an inorganic phase (potassium chloride, with small concentrations of other salts, e.g. vaterite and weddelite) and an organic phase, which is a cocktail of various aromatic compounds, mainly amides, alcohols and acids. These compounds could contribute to the crystallisation of these rare carbonates, as well as other uncommon salts detected on the cave walls, such as syngenite. The presence of phosphates in the urine may further act as a stabilizing agent. Copyright © 2007 John Wiley & Sons, Ltd. [source] Glycoproteomics and glycomics investigation of membrane N -glycosylproteins from human colon carcinoma cellsPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 16 2008Anne-Sophie Vercoutter-Edouart Dr. Abstract Aberrant glycosylation of proteins is known to profoundly affect cellular adhesion or motility of tumoral cells. In this study, we used HT-29 human colon epithelial cancer cells as a cellular model of cancer progression, as they can either proliferate or differentiate into enterocyte phenotype. A glycoproteomic approach based on Con A lectin-affinity chromatography, SDS-PAGE and MS analysis, allowed the identification of membrane N -glycoproteins from Triton X-100-solubilized proteins from membrane preparation. Among them, 65% were membrane proteins, and 45% were known to be N -glycosylated, such as , chains integrin and dipeptidyl isomerase IV. By lectin-blot analysis, significant changes of ,-2,3- and ,-2,6-sialylation of membrane glycoproteins were observed between proliferating and differentiated HT-29 cells. From these results, nano-LC-MS/MS analysis of the tryptic digests of the corresponding bands was performed and led to the identification of several transmembrane glycoproteins, like members of the solute carrier family and adhesion proteins. Finally, we compared N -glycans profiles and monosaccharide composition of proliferating and enterocyte-like HT-29 cells using MALDI-MS and GC-MS analyses of permethylated derivatives. This glycomic approach allowed to underscore significant changes in N -glycans structure, in particular the expression of atypical N -acetylglucosamine (GlcNAc)-ended N -glycans in enterocyte-like HT-29 cells. [source] Biphasic oligomerization of ethylene with nickel complexes immobilized in organochloroaluminate ionic liquidsAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2009Lixia Pei Abstract Ethylene was selectively oligomerized by nickel complexes such as (PPh3)2NiBr2 and (PPh3)2NiCl2 immobilized in chloroaluminate ionic liquid in biphasic catalytic reactions. The influence of reaction parameters such as reaction media, reaction temperature and Et2AlCl:Ni molar ratio was also evaluated. Turnover frequency up to 24000 mol C2H4/(mol Ni h) was achieved under mild reaction conditions (0.5 atm and 40 °C). GC-MS analyses showed that the obtained oligomers completely consist of C4 and C6. The olefinic products can be easily separated from the catalytic ionic liquid phase by simple decantation, and the nickel catalyst can be reused without a significant decrease in turnover frequency and change of the distribution of the olefinic products. Copyright © 2009 John Wiley & Sons, Ltd. [source] Supercritical CO2 Extraction of Essential Oil from Algerian Rosemary (Rosmarinus officinalis,L.)CHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 3 2010A. Zermane Abstract The present study presents experimental results concerning the supercritical CO2 extraction of essential oil from Algerian rosemary leaves. The effects of key operating parameters such as pressure, temperature, particle size and CO2 mass flow rate on the extraction yield were investigated. The obtained yields were in the range of 0.95,3.52,g oil/g dry rosemary, and the best value was observed at a pressure of 22,MPa, a temperature of 40,°C, a flow rate of 7,g/min, and a particle size of 1,mm. The performance of the local rosemary used was assessed by comparison of the obtained yields with values reported in the literature for essential oils derived from different rosemary sources. The GC and the GC-MS analyses showed that the major compound detected in the essential oil was camphor, at 48.89,wt,%. [source] P71 Metabolism of delta-3-Carene by human cytochrom 450 enzymesCONTACT DERMATITIS, Issue 3 2004Mike Duisken Occupational exposure to monoterpenes occurs in saw mills, particle-board plants, carpentry shops and other types of wood-treating industries. The bicyclic monoterpene delta-3-Carene, one of the components of turpentine, may irritate the skin and muceous membranes and prolonged exposure may result in allergic contact dermatitis or chronic lung function impairment. The effects of low concentrations of delta-3-Carene on alveolar macrophages in vitro were examined and a dose-dependent relationship between the cell viability and the delta-3-Carene concentration was found. Little is known about the metabolism of delta-3-Carene in mammalians. In order to determine the toxic potential of this monoterpene we studied the human metabolism of delta-3-Carene in vitro. Therefore we used pooled human liver S9 and human liver microsomal cytochrome P450 enzymes. By using GC-MS analysis we found one main metabolite produced at high rates. The structure was identified by its mass spectra. The mass fragmentation indicated hydroxylation in allyl position. After synthesis of the assumed product in a four step reaction, it was characterized as delta-3-Carene-10-ol. There was a clear correlation between the concentration of the metabolite production, incubation time and enzyme concentration, respectively. Kinetic analysis showed that Km and Vmax values for the oxidation of delta-3-Carene by human liver microsomes were 0.39 ,M and 0.2 nmol/min/nmol P450. It is the first time that delta-3-Carene-10-ol is described as human metabolite of delta-3-Carene. [source] A novel coupled enzyme assay reveals an enzyme responsible for the deamination of a chemically unstable intermediate in the metabolic pathway of 4-amino-3-hydroxybenzoic acid in Bordetella sp. strain 10dFEBS JOURNAL, Issue 15 2004Chika Orii 2-Amino-5-carboxymuconic 6-semialdehyde is an unstable intermediate in the meta -cleavage pathway of 4-amino-3-hydroxybenzoic acid in Bordetella sp. strain 10d. In vitro, this compound is nonenzymatically converted to 2,5-pyridinedicarboxylic acid. Crude extracts of strain 10d grown on 4-amino-3-hydroxybenzoic acid converted 2-amino-5-carboxymuconic 6-semialdehyde formed from 4-amino-3-hydroxybenzoic acid by the first enzyme in the pathway, 4-amino-3-hydroxybenzoate 2,3-dioxygenase, to a yellow compound (,max = 375 nm). The enzyme in the crude extract carrying out the next step was purified to homogeneity. The yellow compound formed from 4-amino-3-hydroxybenzoic acid by this purified enzyme and purified 4-amino-3-hydroxybenzoate 2,3-dioxygenase in a coupled assay was identified as 2-hydroxymuconic 6-semialdehyde by GC-MS analysis. A mechanism for the formation of 2-hydroxymuconic 6-semialdehyde via enzymatic deamination and nonenzymatic decarboxylation is proposed based on results of spectrophotometric analyses. The purified enzyme, designated 2-amino-5-carboxymuconic 6-semialdehyde deaminase, is a new type of deaminase that differs from the 2-aminomuconate deaminases reported previously in that it primarily and specifically attacks 2-amino-5-carboxymuconic 6-semialdehyde. The deamination step in the proposed pathway differs from that in the pathways for 2-aminophenol and its derivatives. [source] Mass spectrometry study of ecto-5,-nucleotidase from bull seminal plasmaFEBS JOURNAL, Issue 16 2000Carlo Fini The structure of ecto-5,-nucleotidase from bull seminal plasma, containing a glycosyl-phosphatidylinositol anchor, was studied using mass spectrometry. MALDI-MS analysis of intact protein indicated a mass of 65 568.2 Da for the monomeric form, and it also showed a heterogeneous population of glycoforms with the glycosidic moiety accounting for ,,6000 Da. MALDI-MS analysis showed that Asn53, Asn311, Asn333 and Asn403 were four sites of N -glycosylation. GC-MS analysis provided information on the glycosidic structures linked to the four asparagines. Asn53, Asn311 and Asn333 were linked to high-mannose saccharide chains, whereas the glycan chains linked to Asn403 contained a heterogeneous mixture of oligosaccharides, the high-mannose type structure being the most abundant and hybrid or complex type glycans being minor components. By combining enzymatic and/or chemical hydrolysis with GC-MS analysis, detailed characterization of the glycosyl-phpsphatidylinositol anchor was obtained. MALDI spectral analysis indicated that the glycosyl-phosphatidylinositol core contained EtN(P)Man3GlcNH2 -myo-inositol(P)-glycerol, principally modified by stearoyl and palmitoyl residues or by stearoyl and myristoyl residues to a minor extent. Moreover, 1-palmitoylglycerol and 1-stearoylglycerol outweighed 2-palmitoylglycerol and 2-stearoylglycerol. The combination of chemical and enzymatic digestions of the protein with the mass spectral analysis yielded a complete pattern of S,S bridges. The protein does not contain free thiols and its eight cysteines are linked by intramolecular disulfide bonds, the pairs being: Cys51,Cys57, Cys353,Cys358, Cys365,Cys387 and Cys476,Cys479. This work resolves details of the structure of ecto-5,-nucleotidase, with particular regard to the localization and composition of the glycidic moiety, number and localization of the disulfide bridges and characterization of the glycosyl-phosphatidylinositol anchor. [source] Composition and antimicrobial activity of the essential oil of Micromeria cristata and Micromeria julianaFLAVOUR AND FRAGRANCE JOURNAL, Issue 1 2006Gordana Stojanovi Abstract The chemical composition of the essential oil of Micromeria cristata and Micromeria juliana was determined by GC-MS analysis. Among the 36 identified compounds of the M. cristata essential oil, isoborneol (11.3%), borneol (8.5%), verbenone (8.2%), 10- epi - , -cadinol and thujan-3-ol, were found to be major components. The main constituents of the M. juliana oil were verbenol (11.8%), thymol (10.8%), caryophyllene oxide (10.5%), borneol (9.3%) and myrtenal (7.1%). The in-vitro antimicrobial activity of the ethanolic solution of the essential oils was investigated by the disk diffusion method with ampicillin as the standard antibiotic against six microorganisms (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Salmonella enteritidis and Aspergillus niger). At 1:20 dilution the activity of both oils was moderate while at 1:40 dilution the oils showed weak or no activity. Copyright © 2005 John Wiley & Sons, Ltd. [source] (11Z)-hexadec-11-enal enhances the attractiveness of Diatraea saccharalis main pheromone component in wind tunnel experimentsJOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2005B. Kalinová Abstract:, GC-EAD and GC-MS analysis of pheromone gland extracts of sugarcane borer, Diatraea saccharalis, revealed two antennally active compounds, (9Z,11E)-hexadeca-9,1-dienal and (11Z)-hexadec-11-enal, in approximately 10 : 1 ratio. Various doses of identified compounds were investigated in wind tunnel experiments individually and in a 10 : 1 ratio. At all tested doses (9Z,11E)-hexadeca-9,1-dienal alone elicited upwind orientation and source location only in a minority of tested males. An admixture of (11Z)-hex-11-enal enhanced the attractiveness of (9Z,11E)-hexadeca-9,11-dienal significantly. This two-component blend (100 pg) was as attractive as natural pheromone extracted from three female pheromone glands. The data suggest that (11Z)-hexadec-11-enal is a part of the D. saccharalis sex pheromone. [source] Hydrocarbon degradation by thermophilic Nocardia otitidiscaviarum strain TSH1: physiological aspectsJOURNAL OF BASIC MICROBIOLOGY, Issue 6 2007Majid Zeinali Abstract Indigenous thermophilic hydrocarbon degraders are of special significance for the bioremediation of oil-contaminated desert soils with ambient temperature of 45,50 °C. The first objective of this study was to demonstrate the hydrocarbon-degrading capability of Nocardia otitidiscaviarum TSH1 (DSM 45036) which grows optimally at 50 °C. Analysis of the metabolic profile of the strain TSH1 showed that it could metabolize phenol, intermediate-chain-length n -alkanes and some polycyclic aromatic hydrocarbons (PAHs) ranging in size from two to four fused rings efficiently, but not toluene and xylene. N. otitidiscaviarum TSH1 was able to survive and grow at phenol concentrations up to 875 mg l,1. For the first time, the physiological response of a thermophilic Nocardia strain to poorly available hydrophobic compounds was also investigated. When grown on a mineral salt medium with hexadecane, N. otitidiscaviarum TSH1 showed very high affinity for the organic phase. Additionally, PAH-grown cells were considerably hydrophobic. The capacity of PAH-utilizing N. otitidiscaviarum TSH1 isolate to produce biosurfactants was also investigated. Fatty acids (C14,C18) were detected by GC-MS analysis during bacterial growth in PAH supplemented mineral media. High cell surface hydrophobicity and capability of N. otitidiscaviarum TSH1 to degrade different hydrocarbons at 50 °C may make it an ideal candidate to treat oil-contaminated desert soils. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Essential Oil of,Aegle marmelos,as a Safe Plant-Based Antimicrobial Against Postharvest Microbial Infestations and Aflatoxin Contamination of Food CommoditiesJOURNAL OF FOOD SCIENCE, Issue 6 2009Priyanka Singh ABSTRACT:, The essential oil of,Aegle marmelos,L. Correa (Rutaceae) showed strong fungitoxicity against some storage fungi-causing contamination of foodstuffs. The oil also showed efficacy as aflatoxin suppressor at 500 ,L/L as it completely arrested the aflatoxin B1 production by the toxigenic strains (Navjot 4NSt and Saktiman 3NSt) of,Aspergillus flavus,Link. Keeping in view the side effects of synthetic fungicides,,A. marmelos,oil may be recommended as an antimicrobial of plant origin to enhance the shelf life of stored food commodities by controlling the fungal growth as well as aflatoxin secretion. This is the 1st report on aflatoxin B1 inhibitory nature of this oil.,A. marmelos,oil may be recommended as a novel plant-based antimicrobial in food protection over synthetic preservatives, most of which are reported to incite environmental problems because of their nonbiodegradable nature and side effects on mammals. The LD50 of,Aegle,oil was found to be 23659.93 mg/kg body weight in mice (Mus musculus,L.) when administered for acute oral toxicity showing nonmammalian toxicity of the oil. GC-MS analysis of the oil found DL-Limonene to be major component. [source] The synthesis of multiply 13C-labelled plant and mammalian lignans as internal standards for LC-MS and GC-MS analysisJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 13 2005Tara Fryatt Abstract The syntheses of multiply 13C-labelled derivatives of the two mammalian lignans, enterolactone and enterodiol, and two of their plant lignan precursors, secoisolariciresinol and matairesinol, are described. Three 13C atoms were incorporated into each lignan using potassium [13C]cyanide as the source for all of the 13C atoms. The compounds were prepared for use as internal standards in the LC-MS and GC-MS analysis of lignans. Copyright © 2005 John Wiley & Sons, Ltd. [source] GC-MS analysis of multiply derivatized opioids in urineJOURNAL OF MASS SPECTROMETRY (INCORP BIOLOGICAL MASS SPECTROMETRY), Issue 8 2007Bud-Gen Chen Abstract Opiates such as hydrocodone, hydromorphone, oxycodone, noroxycodone, and oxymorphone reportedly may interfere with the analysis of morphine and codeine. The analysis of these compounds themselves also is an important issue. Thus, double derivatization approaches utilizing methoxyamine and hydroxylamine to first form oxime products with keto-opiates, followed by the derivatization with trimethylsilyl (TMS) or propionyl groups, have been developed for the simultaneous analysis of these compounds. However, these studies have not included all compounds of interest and resulted in inadequate chromatographic resolution or significant intensity cross-contribution between the ions designating the analyte and its deuterated internal standard for certain compounds. By exploring three-step derivatization approaches with the combination of various derivatization groups and orders, this study concluded that application of methoxyimino/propionyl/TMS groups, in the order listed, facilitated the simultaneous analysis of eight opiates (morphine, 6-acetylmorphine, hydromorphone, oxymorphone, codeine, hydrocodone, oxycodone and noroxycodone) in urine samples, achieving satisfactory limits of quantitation and detection. In addition, the adapted approach resulted in two usable products for morphine and codeine providing alternatives, should interferences render any of these products non-usable. Copyright © 2007 John Wiley & Sons, Ltd. [source] GC-MS analysis of organic compounds in wastewater and sewage sludgeJOURNAL OF SEPARATION SCIENCE, JSS, Issue 1 2008Axel Patrick Ligon Abstract A multimethod based on liquid,liquid extraction and solid,liquid extraction for the analysis of persistent organic pollutants in water and sludge from sewage treatment plants has been established. Traces of 22 organic compounds used in industry and personal care products (PCPs) were analyzed by GC/MS. The LODs for the analytes were less than 2.3 ng/L for wastewater and 31 ,g/kg (dry weight matter) for sewage sludge. Satisfactory recoveries (70,130%) were achieved. The validated method permits the analysis of water and sludge samples at various stages of the treatment from different sewage treatment plants. Thus, the distribution between water and sludge as well as the dissipation of the compounds analyzed were balanced. By this means, the efficiency of different wastewater treatment plants (WWTPs) can be evaluated and measures can be taken to optimize the treatment process at different stages. [source] Rapid TLC/GC-MS identification of acetylcholinesterase inhibitors in alkaloid extractsPHYTOCHEMICAL ANALYSIS, Issue 5 2008Strahil Berkov Abstract Alkaloid extracts from 12 plant species of the families Amaryllidaceae, Fumariacae and Papaveraceae were studied with respect to their acetylcholinesterase inhibitory activity and alkaloid patterns. Fifty-three alkaloids were identified by GC-MS, including known acetylcholinesterase (AChE) inhibitors such as galanthamine, epigalanthamine, sanguinine and epinorgalanthamine in extracts of Amaryllidaceae plants and protopine in extracts of Fumariaceae and Papaveraceae plants. The galanthamine-containing extracts of the amaryllidaceous plants were found to be the most active while the extract of Corydalis bulbosa was the most active among the extracts of the tested plants from the Fumariaceae and Papaveraceae plants. TLC bioautographic assay, preparative TLC and GC-MS analysis were combined to identify the active compounds in the studied extracts. Galanthamine was isolated from the known AChE inhibitors in the extracts of Amaryllidaceae plants. Corydaline, bulbocapnine and stylopine were found to be active in the extracts of plant species of the families Fumariaceae and Papaveraceae. Available standards of deshydrocorydaline,a precursor of corydaline, corydaline and stylopine,were tested for AChE inhibitory activity. Deshydrocorydaline and corydaline showed potent inhibitory activity comparable with that of the positive control galanthamine. Copyright © 2008 John Wiley & Sons, Ltd. [source] Chemical composition and antiproliferative activity of essential oil from the leaves of a medicinal herb, Schefflera heptaphyllaPHYTOTHERAPY RESEARCH, Issue 1 2009Yao-Lan Li Abstract Schefflera heptaphylla (L.) Frodin is a medicinal herb widely used as a main ingredient of the popular health tea formulation against infections in Southern China. Twenty-seven volatile compounds were identified by GC-MS analysis from the essential oil obtained from the leaves of S. heptaphylla, and 17 of them belonged to monoterpenes or sesquiterpenes. The main volatile constituent in S. heptaphylla was found to be a monoterpene, , -pinene, comprising about 22% of the total volatile components. The essential oil showed significant antiproliferative activity against three cancer cell lines, MCF-7, A375 and HepG2 cells, with IC50 values of 7.3 µg/mL, 7.5 µg/mL and 6.9 µg/mL, respectively. The result of the cytotoxicity assay indicates that (,)- , -pinene and (+)- , -pinene (commercially available from Sigma) also possessed antiproliferative activity against the cancer cells MCF-7, A375 and HepG2 with IC50 values ranging from 147.1 to 264.7 µm. Copyright © 2008 John Wiley & Sons, Ltd. [source] Fatty acids profile and antiinflammatory activity of Nonea setosa R. et S.PHYTOTHERAPY RESEARCH, Issue 5 2006Massimo Curini Abstract In order to verify the antiinflammatory properties of Nonea setosa R. et S. (Fam. Boraginaceae) and to identify the relevant active principles, aerial parts of this plant were extracted with increasing polarity solvents. The antiinflammatory activity was investigated by a bioassay-oriented fractionation using the inhibition of the croton oil-induced ear oedema in mice as an experimental model of inflammation. GC-MS analysis of the most active fraction revealed the presence of high amounts of polyunsaturated fatty acids. Copyright © 2006 John Wiley & Sons, Ltd. [source] Antimicrobial activity of essential oil and methanol extracts of Achillea sintenisii Hub.PHYTOTHERAPY RESEARCH, Issue 9 2003Mor. (Asteraceae) Abstract The essential oil, obtained by Clevenger distillation, and water-soluble and water-insoluble parts of the methanol extracts of Achillea sintenisii Hub. Mor. were individually assayed for their antimicrobial activities against 12 bacteria and two yeasts, Candida albicans and C. krusei. No activity was exhibited by the water-soluble subfraction, whereas both the water-insoluble subfraction of the methanol extracts and the essential oil were found to be active against some test microorganisms studied. Since the essential oil possessed stronger activity than the other extracts tested, it was further fractionated and the fractions were evaluated for their antimicrobial activity, followed by GC-MS analysis, resulting in the identi,cation of 32 compounds which constituted 90.2% of the total oil. The GC-MS analysis of the oil and its fractions revealed that the main components of the oil, e.g. camphor and eucalyptol, possessed appreciable activity against C. albicans and Clostridium perfringens. The ,ndings presented here also suggest that the other constituents of the oil, e.g. borneol and piperitone can also be taken into account for the activity observed. Copyright © 2003 John Wiley & Sons, Ltd. [source] Effect of arbuscular mycorrhizal (AM) colonization on terpene emission and content of Artemisia annua L.PLANT BIOLOGY, Issue 1 2008F. Rapparini Abstract Plant roots interact with a wide variety of rhizospheric microorganisms, including bacteria and the symbiontic arbuscular mycorrhizal (AM) fungi. The mycorrhizal symbiosis represents a series of complex feedbacks between plant and fungus regulated by their physiology and nutrition. Despite the widespread distribution and ecological significance of AM symbiosis, little is known about the potential of AM fungi to affect plant VOC metabolism. The purpose of this study was to investigate whether colonization of plant roots by AM fungi and associated soil microorganisms affects VOC emission and content of Artemisia annua L. plants (Asteraceae). Two inoculum types were evaluated: one consisted of only an arbuscular mycorrhizal (AM) fungus species (Glomus spp.), and the other was a mixture of different Glomus species and associated soil bacteria. Inoculated plants were compared with non-inoculated plants and with plants supplemented with extra phosphorus (P) to obtain plants of the same size as mycorrhizal plants, thus excluding potentially-confounding mycorrhizal effects on shoot growth. VOC emissions of Artemisia annua plants were analyzed by leaf cuvette sampling followed by off-line measurements with pre-concentration and gas chromatography mass spectrometry (GC-MS). Measurements of CO2 and H2O exchanges were conducted simultaneously. Several volatile monoterpenes were identified and characterized from leaf emissions of Artemisia annua L. by GC-MS analysis. The main components identified belong to different monoterpene structures: ,-pinene, ,-pinene, camphor, 1,8-cineole, limonene, and artemisia ketone. A good correlation between monoterpene leaf concentration and leaf emission was found. Leaf extracts included also several sesquiterpenes. Total terpene content and emission was not affected by AM inoculation with or without bacteria, while emission of limonene and artemisia ketone was stimulated by this treatment. No differences were found among treatments for single monoterpene content, while accumulation of specific sesquiterpenes in leaves was altered in mycorrhizal plants compared to control plants. Growth conditions seemed to have mainly contributed to the outcome of the symbiosis and influenced the magnitude of the plant response. These results highlight the importance of considering the below-ground interaction between plant and soil for estimating VOC emission rates and their ecological role at multitrophic levels. [source] Development of a simultaneous liquid,liquid extraction and chiral derivatization method for stereospecific GC-MS analysis of amphetamine-type stimulants in human urine using fractional factorial designBIOMEDICAL CHROMATOGRAPHY, Issue 9 2008W. R. Wan Aasim Abstract A stereospecific gas chromatography,mass spectrometry analysis method for amphetamine-type stimulants in human urine was recently developed. For maximum efficiency, liquid,liquid extraction and chiral derivatization of the analytes using (R)-(,)- , -methoxy- , -(trifluoromethyl)phenylacetyl chloride were performed simultaneously. The effects of (1) use of saturated sodium chloride in 2.0 m sodium hydroxide, (2) extraction solvent volume, (3) percentage of triethylamine, (4) derivatization reagent volume, (5) sample mixing time, (6) incubation temperature and (7) incubation time on method sensitivity and variability were assessed using a two-level, eight-run Plackett,Burman design followed by a fold-over design. The use of saturated sodium chloride solution and the derivatization reagent volume were significant factors (ANOVA, p < 0.01). The saturated sodium chloride solution decreased sensitivity whereas an increased volume of derivatization reagent increased sensitivity. Calibration curves for all analytes were linear between 5 and 500 µg/L, with correlation coefficients of >0.99. Detection limits were ,2.3 µg/L and quantitation limits ,7.7 µg/L. Reproducibility was good, with relative standard deviation values at <20%. Recovery exceeded 100% for most analytes. The experimental design enabled easy and rapid identification of significant factors using a minimal number of samples. This method has good potential for studies requiring rapid and sensitive stereospecific quantification of amphetamine-type stimulants. Copyright © 2008 John Wiley & Sons, Ltd. [source] GC-MS analysis of penta- and tetra-cyclic triterpenes from resins of Pistacia species.BIOMEDICAL CHROMATOGRAPHY, Issue 8 2005Part II. Abstract Pistacia species contain oleoresins with bioactive triterpenes. In this study triterpenes, including minor components, were identified and quantified in both neutral and acidic fractions of Pistacia terebinthus var. Chia resin, grown exclusively in Chios island (Greece), collected traditionally, as well as using stimulating agents (liquid collection). It was proved that these two resin samples were composed of several different minor triterpenes, while major constituents were similar but in different proportions. Compounds that differentiated two resin samples of P. lentiscus and P. terebinthus var. Chia, both traditionally collected, were detected, in order to identify the nature of resins present in archaeological materials. In the traditionally collected resin, 37 triterpenes were identified, 12 in the acidic and 25 in the neutral fraction. In the liquid collection resin 10 compounds were identified in the acidic and 23 in the neutral fraction, while 16 compounds were not contained in the traditionally collected resin. The main triterpenes in both resin samples collected traditionally and using stimulating agents were: isomasticadienonic acid (23.6 and 26.3% w[sol ]w of the triterpenic fraction, respectively), 28-norolean-17-en-3-one (16.3 and 17.5% w[sol ]w of the triterpenic fraction, respectively) and masticadienonic acid (5.8 and 6.0% w[sol ]w of the triterpenic fraction). In this study the qualitative and quantitative composition of triterpenes was compared in the Pistacia lentiscus and P. terebinthus var. Chia resin samples collected with the traditional and new liquid techniques, and also triterpenes in resins of P. terebinthus obtained by the traditional technique and using stimulating agents. The aim of the study was also to examine whether the collection technique influenced the triterpenes contained in P. terebinthus var. Chia resin samples. Copyright © 2005 John Wiley & Sons, Ltd. [source] | ||||||||||||||||