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  • 1
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 04 May 2010, Vol.107(18), pp.8147-52
    Description: It has been firmly established that humans excrete a small but steady amount of the isoquinoline alkaloid morphine in their urine. It is unclear whether it is of dietary or endogenous origin. There is no doubt that a simple isoquinoline alkaloid, tetrahydropapaveroline (THP), is found in human and rodent brain as well as in human urine. This suggests a potential biogenetic relationship between both alkaloids. Unlabeled THP or [1,3,4-D(3)]-THP was injected intraperitoneally into mice and the urine was analyzed. This potential precursor was extensively metabolized (96%). Among the metabolites found was the phenol-coupled product salutaridine, the known morphine precursor in the opium poppy plant. Synthetic [7D]-salutaridinol, the biosynthetic reduction product of salutaridine, injected intraperitoneally into live animals led to the formation of [7D]-thebaine, which was excreted in urine. [N-CD(3)]-thebaine was also administered and yielded [N-CD(3)]-morphine and the congeners [N-CD(3)]-codeine and [N-CD(3)]-oripavine in urine. These results show for the first time that live animals have the biosynthetic capability to convert a normal constituent of rodents, THP, to morphine. Morphine and its precursors are normally not found in tissues or organs, presumably due to metabolic breakdown. Hence, only that portion of the isoquinoline alkaloids excreted in urine unmetabolized can be detected. Analysis of urine by high resolution-mass spectrometry proved to be a powerful method for tracking endogenous morphine and its biosynthetic precursors.
    Keywords: Morphine -- Biosynthesis
    ISSN: 00278424
    E-ISSN: 1091-6490
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  • 2
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 2011, Vol.108(5), pp.1955-1960
    Description: Leaf-cutting ants cultivate the fungus Leucoagaricus gongylophorus, which serves as a major food source. This symbiosis is threatened by microbial pathogens that can severely infect L. gongylophorus. Microbial symbionts of leaf-cutting ants, mainly Pseudonocardia and Streptomyces, support the ants in defending their fungus gardens against infections by supplying antimicrobial and antifungal compounds. The ecological role of microorganisms in the nests of leaf-cutting ants can only be addressed in detail if their secondary metabolites are known. Here, we use an approach for the rapid identification of established bioactive compounds from microorganisms in ecological contexts by combining phylogenetic data, database searches, and liquid chromatography electrospray ionisation high resolution mass spectrometry (LC-ESI-HR-MS) screening. Antimycins A₁-A₄, valinomycins, and actinomycins were identified in this manner from Streptomyces symbionts of leaf-cutting ants. Matrix-assisted laser desorption ionization (MALDI) imaging revealed the distribution of valinomycin directly on the integument of Acromyrmex echinatior workers. Valinomycins and actinomycins were also directly identified in samples from the waste of A. echinatior and A. niger leaf-cutting ants, suggesting that the compounds exert their antimicrobial and antifungal potential in the nests of leaf-cutting ants. Strong synergistic effects of the secondary meta-bolites produced by ant-associated Streptomyces were observed in the agar diffusion assay against Escovopsis weberi. Actinomycins strongly inhibit soil bacteria as well as other Streptomyces and Pseudonocardia symbionts. The antifungal antimycins are not only active against pathogenic fungi but also the garden fungus L. gongylophorus itself. In conclusion, secondary metabolites of microbial symbionts of leaf-cutting ants contribute to shaping the microbial communities within the nests of leaf-cutting ants. ; Includes references ; p. 1955-1960.
    Keywords: Ants -- Research ; Symbiosis -- Research ; Microbial Colonies -- Research;
    ISSN: 0027-8424
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  • 3
    Language: English
    In: Phytochemistry, July, 2013, Vol.91, p.81(7)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.phytochem.2012.07.021 Byline: Souvik Kusari (a), Shree P. Pandey (b), Michael Spiteller (a) Keywords: Endophytic fungi; Insect herbivores; Plant-endophyte interaction; Molecular signaling Abstract: Highlighted are poorly investigated interactions that endophytes have with host plants, insect herbivores and with each other, and the diverse molecular mechanisms that might trigger similar chemical responses in both plants and endophytes. Elucidating such networks can enhance discovery of desirable endophytes and further sustain production of host plant compounds using the isolated endophytes. Display Omitted Author Affiliation: (a) Institute of Environmental Research (INFU) of the Faculty of Chemistry, Chair of Environmental Chemistry and Analytical Chemistry, TU Dortmund, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany (b) Department of Biological Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur Campus, PO. BCKV Campus Main Office, Mohanpur, Nadia, West Bengal 741252, India Article Note: (dedication) This manuscript is dedicated to the memory of the late Professor Dr. Meinhart Zenk (Zenk Memorial issue of Phytochemistry).
    Keywords: Plant Metabolites ; Plants (Organisms)
    ISSN: 0031-9422
    Source: Cengage Learning, Inc.
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  • 4
    Language: English
    In: Proceedings of the National Academy of Sciences of the United States of America, 01 February 2011, Vol.108(5), pp.1955-60
    Description: Leaf-cutting ants cultivate the fungus Leucoagaricus gongylophorus, which serves as a major food source. This symbiosis is threatened by microbial pathogens that can severely infect L. gongylophorus. Microbial symbionts of leaf-cutting ants, mainly Pseudonocardia and Streptomyces, support the ants in defending their fungus gardens against infections by supplying antimicrobial and antifungal compounds. The ecological role of microorganisms in the nests of leaf-cutting ants can only be addressed in detail if their secondary metabolites are known. Here, we use an approach for the rapid identification of established bioactive compounds from microorganisms in ecological contexts by combining phylogenetic data, database searches, and liquid chromatography electrospray ionisation high resolution mass spectrometry (LC-ESI-HR-MS) screening. Antimycins A(1)-A(4), valinomycins, and actinomycins were identified in this manner from Streptomyces symbionts of leaf-cutting ants. Matrix-assisted laser desorption ionization (MALDI) imaging revealed the distribution of valinomycin directly on the integument of Acromyrmex echinatior workers. Valinomycins and actinomycins were also directly identified in samples from the waste of A. echinatior and A. niger leaf-cutting ants, suggesting that the compounds exert their antimicrobial and antifungal potential in the nests of leaf-cutting ants. Strong synergistic effects of the secondary meta-bolites produced by ant-associated Streptomyces were observed in the agar diffusion assay against Escovopsis weberi. Actinomycins strongly inhibit soil bacteria as well as other Streptomyces and Pseudonocardia symbionts. The antifungal antimycins are not only active against pathogenic fungi but also the garden fungus L. gongylophorus itself. In conclusion, secondary metabolites of microbial symbionts of leaf-cutting ants contribute to shaping the microbial communities within the nests of leaf-cutting ants.
    Keywords: Plant Leaves ; Symbiosis ; Ants -- Physiology
    ISSN: 00278424
    E-ISSN: 1091-6490
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  • 5
    Language: English
    In: Analytical chemistry, 20 November 2018, Vol.90(22), pp.13167-13172
    Description: Matrix-assisted laser desorption/ionization imaging high-resolution mass spectrometry (MALDI-imaging-HRMS) is an important technique for visualizing the spatial distribution of compounds directly on the surface of organisms such as microorganisms, insects, plants, animals, and human tissues. However, MALDI-imaging-HRMS and the stable isotope labeling approach have never been combined for the detection and simultaneous visualization of labeled and unlabeled compounds, their analogues and derivatives, as well as their precursors. Herein, we present a methodology that labels microbial secondary metabolites directly on agar with stable isotopes and allows concurrent spatial distribution analyses by MALDI-imaging-HRMS. Using a thin film of labeled agar supplemented with [1-C]-l-proline, [methyl-D]-l-methionine, NHCl, or [N]-l-serine overlaid on unlabeled agar, we demonstrate the incorporation of labeled precursors into prodiginines and serratamolides produced by an endophytic bacterium, Serratia marcescens, by MALDI-imaging-HRMS and HPLC-HRMS. Further, we show the incorporation of CD into prodigiosin as well as its characteristic fragments directly by MALDI-imaging-HRMS. Our methodology has several advantages over currently existing techniques. First, both labeled and unlabeled compounds can be visualized simultaneously in high spatial resolution along with their labeled and unlabeled precursors. Second, by using a thin film of labeled agar, we utilize minimum amounts of expensive labeled compounds (1-3 mg) ensuring a cost-effective method for investigating biosynthetic pathways. Finally, our method allows in situ visualization and identification of target and nontarget compounds without the need of isolating the compounds. This is important for compounds that are produced by microorganisms in low, physiologically, or ecologically relevant concentrations.
    Keywords: Depsipeptides -- Analysis ; Isotope Labeling -- Methods ; Prodigiosin -- Analysis ; Serratia Marcescens -- Chemistry ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization -- Methods
    ISSN: 00032700
    E-ISSN: 1520-6882
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  • 6
    Language: English
    In: Journal of Chromatography A, Oct 19, 2012, Vol.1260, p.111(9)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.chroma.2012.08.060 Byline: Jeong-Heui Choi (a)(b), Marc Lamshoft (a), Sebastian Zuhlke (a), Ki Hun Park (b), Jae-Han Shim (b), Michael Spiteller (a) Keywords: Sedatives; [alpha]-, [beta]-blockers; Accelerated solvent extraction; Dispersive solid-phase extraction; Orbitrap mass spectrometry; Environment-friendly agricultural material Abstract: a* Combination of ASE and LC-Orbitrap MS for sedatives and [alpha]-, [beta]-blockers in blood meal. a* Dispersive solid-phase extraction as an efficient cleanup method. a* Good results of the sensitivity, linearity, accuracy and precision. a* Finding a metabolite of xylazine via the high resolution MS detection. Author Affiliation: (a) Institute of Environmental Research of the Faculty of Chemistry, Dortmund University of Technology, Otto-Hahn-Strasse 6, 44227 Dortmund, Germany (b) Natural Products Chemistry Laboratory, College of Agriculture and Life Science, Chonnam National University, 77 Yongbong-ro, Buk-gu, 500-757 Gwangju, South Korea Article History: Received 20 June 2012; Revised 14 August 2012; Accepted 19 August 2012
    Keywords: Mass Spectrometry ; Adrenergic Beta-antagonists ; Metabolites
    ISSN: 0021-9673
    Source: Cengage Learning, Inc.
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  • 7
    In: Natural Product Reports, 2011, Vol.28(7), pp.1203-1207
    Description: The prospect of endophytes capable of producing associated plant natural products with therapeutic potential is undeniable. However, the unyielding struggle so far to transform these potential sources into sustainable microbial manufacturers on a commercial scale has been disappointing. In this Viewpoint , we address this trade-off between endophyte discovery and viable industrial application.
    Keywords: Biological Products ; Symbiosis ; Fungi -- Chemistry ; Plants -- Microbiology;
    ISSN: 0265-0568
    E-ISSN: 1460-4752
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  • 8
    In: Analytical Methods, 2012, Vol.4(12), pp.4360-4367
    Description: The paper reported a matrix-assisted laser desorption/ionization (MALDI) mass spectrometric (MS) protocol for determination of herbicides, improving the analytical sample preparation step, making a significant contribution to the reproducibility and precision of the method. Matrix-analyte sampling is performed, employing low molecular weight (LMW) dication-containing organic crystals. Considering environmental control applications, six of the best selling herbicides, such as aclonifen ( 1 ), bifenox ( 2 ), diclofop-methyl ( 3 ), racemic mixture of diclofop ( 4 ), alachlor ( 5 ) and metolachlor ( 6 ) as well as their mixtures are quantified successively through the replacement of the polyfunctional benzoic acids with dication-containing organic matrices. The application of classical matrices for UV-MALDI-MS for the analysis of 16 caused their competitive chemical transformation, thus leading to spurious results and inaccurate analytical information, due to the wide variety of experimental conditions depending on the chemical, physico-chemical and physical nature of the herbicide analytes. The full method and technique validation, based on UV-MALDI-MS employing an Orbitrap analyser, are presented, achieving to our knowledge promising measurements for LMW analytes. These latter are judged by a fully validated analytical protocol based on positive electrospray ionization (ESI) mass spectrometry in a single and tandem (MS/MS) mode of operation. The chemical modifications, polymorph transformations of the UV-MALDI-MS crystal matrices and/or matrix-analyte samples, as well as ion-process formation upon solution crystalline state and crystalline state gas-phase transitions is controlled by joint application of unique and robust instrumental analytical methods for absolute structural determination, such as single crystal X-ray diffraction and mass spectrometry. As direct experimental qualitative, quantitative and structural evidence regarding the analytes was provided, the reported protocol is a fully validated one at each of the analytical steps. The additional quantum chemical data allowed correlation of the thermodynamic stability and MS abundances of observed ionic species in the gas-phase as well as the structure of crystals. Since environmental analysis involves a broad variety of analytes, conditions and degree of matrix complexity, only an individual certification method development may achieve meaningful analytical information. In this respect, the reported UV-MALDI-MS method for herbicides significantly impacts the field of environmental analytical chemistry, quality assurance and control; moreover the analytical protocol is constructed to deal with a real environmental problem. Therefore the reported method ensures real practical efficiency and reliability in the results for the human health safety, environmental monitoring and control programs.
    Keywords: Analytical Chemistry ; Crystal Structure ; Herbicides ; Ionization ; Mathematical Analysis ; Matrices ; Matrix Methods ; Transformations ; Instruments and Measurements (So);
    ISSN: 1759-9660
    E-ISSN: 1759-9679
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  • 9
    Language: English
    In: Phytochemistry, Nov, 2012, Vol.83, p.79(8)
    Description: To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.phytochem.2012.06.004 Byline: Simeon Fogue Kouam (a)(b), Souvik Kusari (a), Marc Lamshoft (a), Ostend Kamgue Tatuedom (b), Michael Spiteller (a) Keywords: Entandrophragma cylindricum; Cameroonian medicinal plant; Sapelenin; Anti-inflammatory; Cytotoxic Abstract: In this manuscript, we report the isolation and characterization of sapelenins G-J (1-4), from the Cameroonian medicinal plant, Entandrophragma cylindricum, along with their anti-inflammatory and cytotoxic activities. Display Omitted Author Affiliation: (a) Institute of Environmental Research (INFU) of the Faculty of Chemistry, Chair of Environmental Chemistry and Analytical Chemistry, TU Dortmund, Otto-Hahn-Str. 6, D-44221 Dortmund, Germany (b) Department of Chemistry, Higher Teachers' Training College, University of Yaounde I, P. O. Box 47, Yaounde, Cameroon Article History: Received 26 January 2012; Revised 6 June 2012
    Keywords: Anti-inflammatory Agents ; Herbal Medicine
    ISSN: 0031-9422
    Source: Cengage Learning, Inc.
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  • 10
    Language: English
    In: Chemosphere, October 2017, Vol.185, pp.953-963
    Description: During production of active pharmaceutical ingredients, process waste water is generated at several stages of manufacturing. Whenever possible, the resulting waste water will be processed by conventional waste water treatment plants. Currently, incineration of the process waste water is the method to eliminate compounds with high biological activity. Thus, ozone treatment followed by biological waste water treatment was tested as an alternative method. Two prominent representatives of the large group of fluoroquinolone antibiotics (ciprofloxacin and moxifloxacin) were investigated, focussing on waste water of the bulk production. Elimination of the target compounds and generation of their main transformation products were determined by liquid chromatography – high resolution mass spectrometry (LC-HRMS). The obtained results demonstrated, that the concentration of moxifloxacin and its metabolites can be effectively reduced (〉99.7%) prior entering the receiving water. On the contrary, the concentration of ciprofloxacin and its metabolites remained too high for safe discharge, necessitating application of prolonged ozonation for its further degradation. The required ozonation time can be estimated based on the determined kinetics. To assure a low biological activity the ecotoxicity of the ozonated waste water was investigated using three trophic levels. By means of multiple-stage mass spectrometry (MS ) experiments several new transformation products of the fluoroquinolones were identified. Thus, previously published proposed structures could be corrected or confirmed.
    Keywords: Ozonation ; Ciprofloxacin ; Moxifloxacin ; Ecotoxicology ; Transformation Products ; Chemistry ; Ecology
    ISSN: 0045-6535
    E-ISSN: 1879-1298
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