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Feineis D, Bringmann G. Structural variety and pharmacological potential of naphthylisoquinoline alkaloids. THE ALKALOIDS. CHEMISTRY AND BIOLOGY 2024; 91:1-410. [PMID: 38811064 DOI: 10.1016/bs.alkal.2024.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Naphthylisoquinoline alkaloids are a fascinating class of natural biaryl compounds. They show characteristic mono- and dimeric scaffolds, with chiral axes and stereogenic centers. Since the appearance of the last comprehensive overview on these secondary plant metabolites in this series in 1995, the number of discovered representatives has tremendously increased to more than 280 examples known today. Many novel-type compounds have meanwhile been discovered, among them naphthylisoquinoline-related follow-up products like e.g., the first seco-type (i.e., ring-opened) and ring-contracted analogues. As highlighted in this review, the knowledge on the broad structural chemodiversity of naphthylisoquinoline alkaloids has been decisively driven forward by extensive phytochemical studies on the metabolite pattern of Ancistrocladus abbreviatus from Coastal West Africa, which is a particularly "creative" plant. These investigations furnished a considerable number of more than 80-mostly new-natural products from this single species, with promising antiplasmodial activities and with pronounced cytotoxic effects against human leukemia, pancreatic, cervical, and breast cancer cells. Another unique feature of naphthylisoquinoline alkaloids is their unprecedented biosynthetic origin from polyketidic precursors and not, as usual for isoquinoline alkaloids, from aromatic amino acids-a striking example of biosynthetic convergence in nature. Furthermore, remarkable botanical results are presented on the natural producers of naphthylisoquinoline alkaloids, the paleotropical Dioncophyllaceae and Ancistrocladaceae lianas, including first investigations on the chemoecological role of these plant metabolites and their storage and accumulation in particular plant organs.
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Affiliation(s)
- Doris Feineis
- Institute of Organic Chemistry, University of Würzburg, Würzburg, Germany
| | - Gerhard Bringmann
- Institute of Organic Chemistry, University of Würzburg, Würzburg, Germany.
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Feineis D, Bringmann G. Asian Ancistrocladus Lianas as Creative Producers of Naphthylisoquinoline Alkaloids. PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS 2023; 119:1-335. [PMID: 36587292 DOI: 10.1007/978-3-031-10457-2_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This book describes a unique class of secondary metabolites, the mono- and dimeric naphthylisoquinoline alkaloids. They occur in lianas of the paleotropical Ancistrocladaceae and Dioncophyllaceae families, exclusively. Their unprecedented structures include stereogenic centers and rotationally hindered, and thus likewise stereogenic, axes. Extended recent investigations on six Ancistrocladus species from Asia, as reported in this review, shed light on their fascinating phytochemical productivity, with over 100 such intriguing natural products. This high chemodiversity arises from a likewise unique biosynthesis from acetate-malonate units, following a novel polyketidic pathway to plant-derived isoquinoline alkaloids. Some of the compounds show most promising antiparasitic activities. Likewise presented are strategies for the regio- and stereoselective total synthesis of the alkaloids, including the directed construction of the chiral axis.
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Affiliation(s)
- Doris Feineis
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Gerhard Bringmann
- Institute of Organic Chemistry, University of Würzburg, Am Hubland, 97074, Würzburg, Germany.
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Zavafer A, Ball MC. Good vibrations: Raman spectroscopy enables insights into plant biochemical composition. FUNCTIONAL PLANT BIOLOGY : FPB 2023; 50:1-16. [PMID: 36592984 DOI: 10.1071/fp21335] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 09/20/2022] [Indexed: 06/17/2023]
Abstract
Non-invasive techniques are needed to enable an integrated understanding of plant metabolic responses to environmental stresses. Raman spectroscopy is one such technique, allowing non-destructive chemical characterisation of samples in situ and in vivo and resolving the chemical composition of plant material at scales from microns to metres. Here, we review Raman band assignments of pigments, structural and non-structural carbohydrates, lipids, proteins and secondary metabolites in plant material and consider opportunities this technology raises for studies in vascular plant physiology.
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Affiliation(s)
- Alonso Zavafer
- Plant Science Division, Research School of Biology, The Australian National University, Canberra, ACT 2000, Australia; and Climate Change Cluster, University of Technology Sydney, Ultimo, NSW 2001, Australia; and Present address: Department Biological Sciences and Yousef Haj-Ahmad Department of Engineering, Brock University, St. Catherines, ON, Canada
| | - Marilyn C Ball
- Plant Science Division, Research School of Biology, The Australian National University, Canberra, ACT 2000, Australia
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Erdogdu Y, Saglam S. Infrared, Raman and NMR spectra, conformational stability and vibrational assignment of 7,8-Dihydroxy-4-Methylcoumarin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 132:871-878. [PMID: 24935826 DOI: 10.1016/j.saa.2014.04.074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 04/08/2014] [Accepted: 04/17/2014] [Indexed: 06/03/2023]
Abstract
We report a combined some (infrared, Raman and NMR) spectroscopic and quantum chemistry study on 7,8-Dihydroxy-4-Methylcoumarin molecule (78D4MC). The Raman and IR spectra of 78D4MC molecule were recorded and analyzed in the region 3500-50 cm(-1) and 4000-400 cm(-1), respectively. Potential energy scans were performed at the MMFF level of theory. All possible conformers, which are results at the MMFF level theory, were re-computed at the B3LYP functional with cc-pVDZ basis set. The optimized geometrical parameters, harmonic vibrational wavenumbers and NMR chemical shifts of the most stable conformer were calculated at the B3LYP/6-311G(d,p), cc-pVTZ and cc-pVQZ level in the proximity of the isolated molecule. DFT calculations were combined with Pulay's scaled quantum mechanics force field (SQMFF) methodology in order to fit the theoretical wavenumbers to the experimental ones.
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Affiliation(s)
- Yusuf Erdogdu
- Department of Physics, Ahi Evran University, 40040 Kirsehir, Turkey.
| | - Semran Saglam
- Department of Physics, Gazi University, 06100 Ankara, Turkey
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van Breda SV, van der Merwe CF, Robbertse H, Apostolides Z. Immunohistochemical localization of caffeine in young Camellia sinensis (L.) O. Kuntze (tea) leaves. PLANTA 2013; 237:849-858. [PMID: 23143222 DOI: 10.1007/s00425-012-1804-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 10/30/2012] [Indexed: 06/01/2023]
Abstract
The anatomical localization of caffeine within young Camellia sinensis leaves was investigated using immunohistochemical methods and confocal scanning laser microscopy. Preliminary fixation experiments were conducted with young C. sinensis leaves to determine which fixation procedure retained caffeine the best as determined by high-performance liquid chromatography analysis. High pressure freezing, freeze substitution, and embedding in resin was deemed the best protocol as it retained most of the caffeine and allowed for the samples to be sectioned with ease. Immunohistochemical localization with primary anti-caffeine antibodies and conjugated secondary antibodies on leaf sections proved at the tissue level that caffeine was localized and accumulated within vascular bundles, mainly the precursor phloem. With the use of a pressure bomb, xylem sap was collected using a micro syringe. The xylem sap was analyzed by thin-layer chromatography and the presence of caffeine was determined. We hypothesize that caffeine is synthesized in the chloroplasts of photosynthetic cells and transported to vascular bundles where it acts as a chemical defense against various pathogens and predators. Complex formation of caffeine with chlorogenic acid is also discussed as this may also help explain caffeine's localization.
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Affiliation(s)
- Shane V van Breda
- Department of Biochemistry, University of Pretoria, Lynnwood Road, Hatfield, Pretoria, 0002, Gauteng, South Africa.
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Münchberg U, Wagner L, Spielberg ET, Voigt K, Rösch P, Popp J. Spatially resolved investigation of the oil composition in single intact hyphae of Mortierella spp. with micro-Raman spectroscopy. Biochim Biophys Acta Mol Cell Biol Lipids 2012; 1831:341-9. [PMID: 23032786 DOI: 10.1016/j.bbalip.2012.09.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 09/03/2012] [Accepted: 09/24/2012] [Indexed: 11/25/2022]
Abstract
Zygomycetes are well known for their ability to produce various secondary metabolites. Fungi of the genus Mortierella can accumulate highly unsaturated lipids in large amounts as lipid droplets. However, no information about the spatial distribution or homogeneity of the oil inside the fungi is obtainable to date due to the invasive and destructive analytical techniques applied so far. Raman spectroscopy has been demonstrated to be well suited to investigate biological samples on a micrometre scale. It also has been shown that the degree of unsaturation of lipids can be determined from Raman spectra. We applied micro-Raman spectroscopy to investigate the spatial distribution and composition of lipid vesicles inside intact hyphae. For Mortierella alpina and Mortierella elongata distinct differences in the degree of unsaturation and even the impact of growth conditions are determined from the Raman spectra. In both species we found that the fatty acid saturation in the vesicles is highly variable in the first 600 μm of the growing hyphal tip and fluctuates towards a constant composition and saturation ratio in all of the remaining mycelium. Our approach facilitates in vivo monitoring of the lipid production and allows us to investigate the impact of cultivation parameters on the oil composition directly in the growing hyphae without the need for extensive extraction procedures.
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Affiliation(s)
- Ute Münchberg
- Institute of Physical Chemistry, Friedrich Schiller University Jena, Helmholtzweg 4, 07743 Jena, Germany
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Krafft C, Cervellati C, Paetz C, Schneider B, Popp J. Distribution of amygdalin in apricot (Prunus armeniaca) seeds studied by Raman microscopic imaging. APPLIED SPECTROSCOPY 2012; 66:644-9. [PMID: 22732534 DOI: 10.1366/11-06521] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Amygdalin is a cyanogenic glycoside found in the seeds of several plants belonging to the Rosaceae family. Cyanogenic glycosides can be specifically probed by Raman spectroscopy due to an inherent nitrile group which shows a well-resolved band near 2245 cm(-1). In the current study the subcellular distribution of amygdalin in thin apricot (Prunus armeniaca) seed sections is probed by high-resolution Raman imaging with a step size of 2.5 μm. Further, Raman images and line maps were collected from four apricot seeds with step sizes between 30 and 70 μm. The data were processed by functional group mapping and the spectral unmixing algorithm vertex component analysis. Spectral contributions of amygdalin, lipids, and cellulose were identified. One seed had low amygdalin content in its center and higher content toward its epidermis. The other three specimens showed different distributions of amygdalin, with highest concentration in the center and local concentration spots throughout the seed. We conclude from these preliminary results on Raman imaging in apricot seeds that amygdalin is unevenly distributed and its location does not follow the same pattern for all seeds. The observed biological variability of the amygdalin distribution cannot yet be explained satisfactorily and requires further investigation.
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Sajan D, Erdogdu Y, Reshmy R, Dereli Ö, Thomas KK, Hubert Joe I. DFT-based molecular modeling, NBO analysis and vibrational spectroscopic study of 3-(bromoacetyl)coumarin. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 82:118-125. [PMID: 21831702 DOI: 10.1016/j.saa.2011.07.013] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2011] [Revised: 06/30/2011] [Accepted: 07/03/2011] [Indexed: 05/31/2023]
Abstract
The NIR-FT Raman and FT-IR spectra of 3-(bromoacetyl)coumarin (BAC) molecule have been recorded and analyzed. Density functional theory (DFT) calculation of two BAC conformers has been performed to find the optimized structures and computed vibrational wavenumbers of the most stable one. The obtained vibrational wavenumbers and optimized geometric parameters were seen to be in good agreement with the experimental data. Characteristic vibrational bands of the pyrone ring and methylene and carbonyl groups have been identified. The lowering of HOMO-LUMO energy gap clearly explains the charge transfer interactions taking place within the molecule.
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Affiliation(s)
- D Sajan
- Department of Physics, Bishop Moore College, Mavelikara, Alappuzha 690110, Kerala, India
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Weissflog I, Vogler N, Akimov D, Dellith A, Schachtschabel D, Svatos A, Boland W, Dietzek B, Popp J. Toward in vivo chemical imaging of epicuticular waxes. PLANT PHYSIOLOGY 2010; 154:604-10. [PMID: 20709828 PMCID: PMC2948993 DOI: 10.1104/pp.110.161786] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2010] [Accepted: 08/03/2010] [Indexed: 05/18/2023]
Abstract
Epicuticular waxes, which are found on the outer surface of plant cuticles, are difficult to study in vivo. To monitor the growth, development, and structural alterations of epicuticular wax layers, coherent anti-Stokes Raman scattering (CARS) might be used. CARS, as a Raman-based technique, not only provides structural insight but also chemical information by imaging the spatial distribution of Raman-active vibrations. Here, we present a comparative study using CARS and scanning electron microscopy to characterize the structure of epicuticular waxes. The ability of CARS to provide detailed structural information on the biologically important wax layer was detailed on the examples of cherry laurel (Prunus laurocerasus), hoya (Hoya carnosa), and ceriman/Swiss cheese plant (Monstera sp. aff. deliciosa). We anticipate that the work presented will open a doorway for online monitoring of formation and alterations of epicuticular wax layers.
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The influence of intracellular storage material on bacterial identification by means of Raman spectroscopy. Anal Bioanal Chem 2010; 397:2929-37. [DOI: 10.1007/s00216-010-3895-1] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2010] [Revised: 05/05/2010] [Accepted: 05/30/2010] [Indexed: 10/19/2022]
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Walter A, Erdmann S, Bocklitz T, Jung EM, Vogler N, Akimov D, Dietzek B, Rösch P, Kothe E, Popp J. Analysis of the cytochrome distribution via linear and nonlinear Raman spectroscopy. Analyst 2010; 135:908-17. [DOI: 10.1039/b921101b] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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12
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Harz M, Rösch P, Popp J. Vibrational spectroscopy--a powerful tool for the rapid identification of microbial cells at the single-cell level. Cytometry A 2009; 75:104-13. [PMID: 19156822 DOI: 10.1002/cyto.a.20682] [Citation(s) in RCA: 161] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Rapid microbial detection and identification with a high grade of sensitivity and selectivity is a great and challenging issue in many fields, primarily in clinical diagnosis, pharmaceutical, or food processing technology. The tedious and time-consuming processes of current microbiological approaches call for faster ideally on-line identification techniques. The vibrational spectroscopic techniques IR absorption and Raman spectroscopy are noninvasive methods yielding molecular fingerprint information; thus, allowing for a fast and reliable analysis of complex biological systems such as bacterial or yeast cells. In this short review, we discuss recent vibrational spectroscopic advances in microbial identification of yeast and bacterial cells for bulk environment and single-cell analysis. IR absorption spectroscopy enables a bulk analysis whereas micro-Raman-spectroscopy with excitation in the near infrared or visible range has the potential for the analysis of single bacterial and yeast cells. The inherently weak Raman signal can be increased up to several orders of magnitude by applying Raman signal enhancement methods such as UV-resonance Raman spectroscopy with excitation in the deep UV region, surface enhanced Raman scattering, or tip-enhanced Raman scattering.
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Affiliation(s)
- M Harz
- Institute of Physical Chemistry, Friedrich-Schiller-Universität Jena, Helmholtzweg 4, Jena 07743, Germany
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Chapter 4 Determination of Alkaloids through Infrared and Raman Spectroscopy. THE ALKALOIDS: CHEMISTRY AND BIOLOGY 2009; 67:217-55. [DOI: 10.1016/s1099-4831(09)06704-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
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Frosch T, Schmitt M, Noll T, Bringmann G, Schenzel K, Popp J. Ultrasensitivein situTracing of the Alkaloid Dioncophylline A in the Tropical LianaTriphyophyllum peltatumby Applying Deep-UV Resonance Raman Microscopy. Anal Chem 2007; 79:986-93. [PMID: 17263326 DOI: 10.1021/ac061526q] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
UV resonance Raman microspectroscopy was applied for a localization of the antiplasmodial naphthylisoquinoline alkaloid dioncophylline A in very low concentrations in different parts of the samples (e.g., in the roots) of the tropical liana Triphyophyllum peltatum. The application of resonance Raman microspectroscopy was characterized by a very high sensitivity and selectivity. It was possible to assign the resonance Raman spectra of dioncophylline A, dioncophylline C, and dioncopeltine A by means of a combination of NIR Raman spectroscopy and DFT calculations. The UV resonance Raman spectra of T. peltatum are very well resembled by the spectra of dioncophylline A, while they can be clearly distinguished from the spectra of dioncophylline C and dioncopeltine A. This distinction between the various naphthylisoquinolines was possible by the two modes at 1356 and 1613 cm-1. These two modes were assigned to C=C stretching and CH bending vibrations. The presented results of a highly sensitive and selective in situ localization of the active agent dioncophylline A in different parts of the plant material of T. peltatum are of high importance for the acquisition of new antimalarials and for plant science in general.
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Affiliation(s)
- Torsten Frosch
- Institut für Physikalische Chemie, Friedrich-Schiller-Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany
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Schulz H, Baranska M. Identification and quantification of valuable plant substances by IR and Raman spectroscopy. VIBRATIONAL SPECTROSCOPY 2007; 43:13-25. [PMID: 0 DOI: 10.1016/j.vibspec.2006.06.001] [Citation(s) in RCA: 433] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
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Shaw LJ, Morris P, Hooker JE. Perception and modification of plant flavonoid signals by rhizosphere microorganisms. Environ Microbiol 2006; 8:1867-80. [PMID: 17014487 DOI: 10.1111/j.1462-2920.2006.01141.x] [Citation(s) in RCA: 131] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Flavonoids are a diverse class of polyphenolic compounds that are produced as a result of plant secondary metabolism. They are known to play a multifunctional role in rhizospheric plant-microbe and plant-plant communication. Most familiar is their function as a signal in initiation of the legume-rhizobia symbiosis, but, flavonoids may also be signals in the establishment of arbuscular mycorrhizal symbiosis and are known agents in plant defence and in allelopathic interactions. Flavonoid perception by, and impact on, their microbial targets (e.g. rhizobia, plant pathogens) is relatively well characterized. However, potential impacts on 'non-target' rhizosphere inhabitants ('non-target' is used to distinguish those microorganisms not conventionally known as targets) have not been thoroughly investigated. Thus, this review first summarizes the conventional roles of flavonoids as nod gene inducers, phytoalexins and allelochemicals before exploring questions concerning 'non-target' impacts. We hypothesize that flavonoids act to shape rhizosphere microbial community structure because they represent a potential source of carbon and toxicity and that they impact on rhizosphere function, for example, by accelerating the biodegradation of xenobiotics. We also examine the reverse question, 'how do rhizosphere microbial communities impact on flavonoid signals?' The presence of microorganisms undoubtedly influences the quality and quantity of flavonoids present in the rhizosphere, both through modification of root exudation patterns and microbial catabolism of exudates. Microbial alteration and attenuation of flavonoid signals may have ecological consequences for below-ground plant-microbe and plant-plant interaction. We have a lack of knowledge concerning the composition, concentration and bioavailability of flavonoids actually experienced by microbes in an intact rhizosphere, but this may be addressed through advances in microspectroscopic and biosensor techniques. Through the use of plant mutants defective in flavonoid biosynthesis, we may also start to address the question of the significance of flavonoids in shaping rhizosphere community structure and function.
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Affiliation(s)
- Liz J Shaw
- Department of Environmental and Geographical Sciences, Manchester Metropolitan University, John Dalton Building, Chester Street, M1 5GD, UK.
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Peetla P, Schenzel KC, Diepenbrock W. Determination of mechanical strength properties of hemp fibers using near-infrared fourier transform Raman microspectroscopy. APPLIED SPECTROSCOPY 2006; 60:682-91. [PMID: 16808870 DOI: 10.1366/000370206777670602] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Fourier transform near-infrared (FT-NIR) Raman microspectroscopy was adopted for analyzing the micro mechanical tensile deformation behavior of cellulosic plant fibers. Mechanical strength parameters such as tensile strength, failure strain, and Young's modulus of diversified hemp fibers were determined within the range of single fiber cells and fiber filaments. The analysis of fiber deformation at the molecular level was followed by the response of a characteristic Raman signal of fiber cellulose that is sensitive to the tensile load applied. The frequency shift of the Raman signal at 1095 cm(-1) to lower wavenumbers was observed when the fibers were subjected to tensile strain. Microstructural investigations using electron microscopy under environmental conditions supported the discussion of mechanical properties of hemp fibers in relation to several fiber variabilities. Generally, mechanical strength properties of diversified hemp fibers were discussed at the molecular, microstructural, and macroscale level. It was observed that mechanical strength properties of the fibers can be controlled in a broad range by appropriate mercerization parameters such as alkali concentration, fiber shrinkage, and tensile stress applied to the fibers during the alkaline treatments.
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Affiliation(s)
- Padmaja Peetla
- Agricultural Department, Martin Luther University Halle-Wittenberg, Ludwig-Wucherer-Strasse 2, D-06108 Halle, Germany
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Frosch T, Schmitt M, Schenzel K, Faber JH, Bringmann G, Kiefer W, Popp J. In vivo localization and identification of the antiplasmodial alkaloid dioncophylline A in the tropical lianaTriphyophyllum peltatum by a combination of fluorescence, near infrared Fourier transform Raman microscopy, and density functional theory calculations. Biopolymers 2006; 82:295-300. [PMID: 16453274 DOI: 10.1002/bip.20459] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Near infrared Fourier transform (NIR FT) micro Raman spectroscopy in combination with density functional theory (DFT) calculations has been applied for an in vivo localization of the antiplasmodial naphthylisoquinoline alkaloid dioncophylline A (1) in the tropical liana Triphyophyllum peltatum. Fluorescence microscopy images suggest finding this active agent in 10 mum big inclusions located in the cortex of the stem or the beginning of the leaves. By means of spatially resolved FT Raman micro spectroscopy, we could detect dioncophylline A (1) in these inclusions. FT Raman spectroscopy is an extremely selective tool capable of differentiating between various structurally similar naphthylisoquinoline alkaloids. With the help of DFT calculations, we succeeded in assigning the differences found in the FT Raman spectra of the various naphthylisoquinolines to nuC=C vibrations of the naphthyl ring. The presented results are of relevance for the investigation and extraction of new antimalarial active agents.
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Affiliation(s)
- Torsten Frosch
- Institut für Physikalische Chemie, Friedrich-Schiller-Universität Jena, Helmholtzweg 4, D-07743 Jena, Germany
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Abstract
Although the physics of Raman spectroscopy and its application to purely chemical problems is long established, it offers a noninvasive, nondestructive, and water-insensitive probe to problems in the life sciences. Starting from the principles of Raman spectroscopy, its advantages, and methods for signal enhancement, the bulk of the review highlights recent applications. Structural investigations of a hormone receptor, testing the biocompatibility of dental implants, probing soil components and plant tissue alkaloids, and localization of single bacteria are just four problems in which Raman spectroscopy offers a solution or complements existing methods.
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Affiliation(s)
- Renate Petry
- Institut für Physikalische Chemie Universität Würzburg Am Hubland, 97074 Würzburg, Germany
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Jähn A, Schröder MW, Füting M, Schenzel K, Diepenbrock W. Characterization of alkali treated flax fibres by means of FT Raman spectroscopy and environmental scanning electron microscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2002; 58:2271-2279. [PMID: 12212753 DOI: 10.1016/s1386-1425(01)00697-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Flax fibres grown under well managed conditions were submitted to NaOH chemical treatments, so called Mercerization. The extent of the polymorphic transformation of cellulose I into cellulose II taking place within the crystalline domains of the fibre cellulose was dependent on the alkali concentration. FT Raman spectroscopy turned out to represent an ideal tool for detecting the polymorphic transformation of the cellulosic fine structure of the flax fibres in vivo. In addition to the differences of the FT Raman spectra in the frequency range below 1500 cm(-1), second derivatives of the spectra in the range of the CH stretching vibrations could also be used to distinguish the two polymorphic modifications. The intensity ratio R of the stretching modes v(s)COC and v(as)COC represents a spectral parameter characterising the molecular structure of the flax fibres. As a supplementary tool, Environmental scanning electron microscopy (ESEM) was used to visualize the microstructural fibre properties dependent on the alkali concentrations during the Mercerization.
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Affiliation(s)
- A Jähn
- Martin Luther University, Institute of Agronomy and Crop Science, Halle, Germany
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Bringmann G, Günther C, Ochse M, Schupp O, Tasler S. Biaryls in nature: a multi-facetted class of stereochemically, biosynthetically, and pharmacologically intriguing secondary metabolites. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE = PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS. PROGRES DANS LA CHIMIE DES SUBSTANCES ORGANIQUES NATURELLES 2002; 82:1-249. [PMID: 11892255 DOI: 10.1007/978-3-7091-6227-9_1] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Affiliation(s)
- G Bringmann
- Institut für Organische Chemie, Universität Würzburg, Germany.
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Schrader B, Dippel B, Erb I, Keller S, Löchte T, Schulz H, Tatsch E, Wessel S. NIR Raman spectroscopy in medicine and biology: results and aspects. J Mol Struct 1999. [DOI: 10.1016/s0022-2860(98)00650-4] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Rösch P, Popp J, Kiefer W. Raman and surface enhanced Raman spectroscopic investigation on Lamiaceae plants. J Mol Struct 1999. [DOI: 10.1016/s0022-2860(98)00624-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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