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121.
Cannabis sativa L. is an important medicinal plant. In order to develop cannabis plant material as a medicinal product quality control and clear chemotaxonomic discrimination between varieties is a necessity. Therefore in this study 11 cannabis varieties were grown under the same environmental conditions. Chemical analysis of cannabis plant material used a gas chromatography flame ionization detection method that was validated for quantitative analysis of cannabis monoterpenoids, sesquiterpenoids, and cannabinoids. Quantitative data was analyzed using principal component analysis to determine which compounds are most important in discriminating cannabis varieties. In total 36 compounds were identified and quantified in the 11 varieties. Using principal component analysis each cannabis variety could be chemically discriminated. This methodology is useful for both chemotaxonomic discrimination of cannabis varieties and quality control of plant material. 相似文献
122.
Ibrahim B. Abdel-Farid Muhammad Jahangir Natali R. Mustafa Nicole M. van Dam Cees A.M.J.J. van den Hondel Hye Kyong Kim Young Hae Choi Robert Verpoorte 《Biochemical Systematics and Ecology》2010
The glucosinolate contents of two different cultivars of Brassica rapa (Herfstraap and Oleifera) infected with Leptosphaeria maculans and Fusarium oxysporum were determined. Infection triggered the accumulation of aliphatic glucosinolates (gluconapin, progoitrin, glucobrassicanapin and gluconapoleiferin) and indole glucosinolate (4-hydroxy-glucobrassicin) in Herfstraap and of two indole glucosinolates (glucobrassicin and 4-hydroxy-glucobrassicin) in Oleifera. While total and aliphatic glucosinolates decreased significantly in Oleifera, a large increase was observed in Herfstraap after fungal infection. The indole glucosinolate glucobrassicin accumulated in Oleifera at a higher rate than Herfstraap especially after infection with F. oxysporum. Apparently the interaction between fungus and B. rapa is cultivar and fungal species specific. 相似文献
123.
Sara Agnolet Jerzy W. Jaroszewski Robert Verpoorte Dan Staerk 《Metabolomics : Official journal of the Metabolomic Society》2010,6(2):292-302
Commercial preparations of Ginkgo biloba are very complex mixtures prepared from raw leaf extracts by a series of extraction and prepurification steps. The pharmacological
activity is attributed to a number of flavonoid glycosides and unique terpene trilactones (TTLs), with largely uncharacterized
pharmacological profiles on targets involved in neurological disorders. It is therefore important to complement existing targeted
analytical methods for analysis of Ginkgo biloba preparations with alternative technology platforms for their comprehensive and global characterization. In this work, 1H NMR-based metabolomics and hyphenation of high-performance liquid chromatography, photo-diode array detection, mass spectrometry,
solid-phase extraction, and nuclear magnetic resonance spectroscopy (HPLC-PDA-MS-SPE-NMR) were used for investigation of 16
commercially available preparations of Ginkgo biloba. The standardized extracts originated from Denmark, Italy, Sweden, and United Kingdom, and the results show that 1H NMR spectra allow simultaneous assessment of the content as well as identity of flavonoid glycosides and TTLs based on a
very simple sample-preparation procedure consisting of extraction, evaporation and reconstitution in acetone-d
6. Unexpected or unwanted extract constituents were also easily identified in the 1H NMR spectra, which contrasts traditional methods that depend on UV absorption or MS ionizability and usually require availability
of reference standards. Automated integration of 1H NMR spectral segments (buckets or bins of 0.02 ppm width) provides relative distribution plots of TTLs based on their H-12
resonances. The present study shows that 1H NMR-based metabolomics is an attractive method for non-selective and comprehensive analysis of Ginkgo extracts. 相似文献
124.
The metabolomic analysis of Brassica rapa leaves treated with methyl jasmonate was performed using 2-dimensional J-resolved NMR spectroscopy combined with multivariate data analysis. The principal component analysis of the J-resolved NMR spectra showed discrimination between control and methyl jasmonate treated plants by principal components 1 and 2. While the level of glucose, sucrose and amino acids showed a decrease after methyl jasmonate treatment, hydroxycinnamates and glucosinolate were highly increased. Methyl jasmonate treatment resulted in a long-term accumulation of indole glucosinolate and indole-3-acetic acid, lasting up to 14 days after treatment. Malate conjugated hydroxycinnamates also exhibited an increase until 14 days after methyl jasmonate treatment, these compounds might play an important role in plant defence responses mediated by methyl jasmonate. 相似文献
125.
K. Škrlep M. Bergant G. M. De Winter B. Bohanec J. Žel R. Verpoorte F. Van Iren M. Camloh 《Biologia Plantarum》2008,52(2):329-333
Different lines of cell suspension cultures of Taxus × media Rehd. and Taxus floridana Nutt. were cryopreserved with a two-step freezing method using a simple and inexpensive freezing container instead of a programmable
freezer. Four to seven days old suspension cell cultures were precultured in growth medium supplemented with 0.5 M mannitol
for 2 d. The medium was then replaced with cryoprotectant solution (1 M sucrose, 0.5 M glycerol and 0.5 M dimethylsulfoxide)
and the cells incubated on ice for 1 h. Before being plunged into liquid nitrogen, cells were frozen with a cooling rate of
approximately −1 °C per min to −80 °C. The highest post-thaw cell viability was 90 %. The recovery was line dependent. The
cryopreservation procedure did not alter the nuclear DNA content of the cell lines. The results indicate that cryopreservation
of Taxus cell suspension cultures using inexpensive freezing container is possible. 相似文献
126.
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128.
Kashif Ali Muzamal Iqbal Nancy Dewi Yuliana Yeon-Ju Lee Seungil Park Saem Han Jeong-Woo Lee Hyi-Seung Lee Robert Verpoorte Young Hae Choi 《Metabolomics : Official journal of the Metabolomic Society》2013,9(4):778-785
Marine sponges are relatively less explored for their chemical features but highly anticipated resource for bioactive compounds. In this paper we report the screening of marine sponges crude extracts for their potential to bind the adenosine A1 receptor. Many samples showed very promising activity and in order to identify the active components, a metabolomics-chemometrics approach is employed. Nuclear magnetic resonance spectroscopy is used for the metabolic profiling of the marine sponges and partial least squares (PLS) and orthogonal PLS (OPLS) algorithms are used to correlate the metabolomics with bioactivity data. Using several two dimensional-NMR techniques, the resonances responsible for the separation of high activity samples from the medium and low activity samples were identified as associated to metabolites like halisulfate 1, halisulfate 3–5, and suvanine (1–5), all belongs to sesterterpenes class. The reference compounds for these metabolites are also tested for the activity, which endorse the findings of the applied methodology. 相似文献
129.
van Midwoud PM Rieux L Bischoff R Verpoorte E Niederländer HA 《Journal of proteome research》2007,6(2):781-791
Poor repeatability of peak areas is a problem frequently encountered in peptide analysis with nanoLiquid Chromatography coupled on-line with Mass Spectrometry (nanoLC-MS). As a result, quantitative analysis will be seriously hampered unless the observed variability can be corrected in some way. Currently, labeling techniques or addition of internal standards are often applied for this purpose. However, these procedures are elaborate and error-prone and may render complex samples even more complex. Moreover, whenever poor repeatability results from variable recovery, not just quantification, but also sensitivity is affected. We have studied the parameters influencing the repeatability of chromatographic peak areas for a model set of proteolytic peptides (i.e., a cytochrome c tryptic digest) in nanoLC-MS analysis. It is demonstrated that repeatability issues are mainly due to poor recovery of peptides from the sample vial. Problems are largely resolved by addition of an organic modifier to the sample vial to improve solubility of the peptides, but care needs to be taken not to lose peptides due to reduced affinity for reversed-phase materials. Good results are obtained when applying dimethylsulfoxide (DMSO) for this purpose. When applying DMSO, repeatability increases, and the limit of detection (LOD) decreases. For the most hydrophobic peptides, a gain in LOD of at least an order of magnitude is obtained. In an aqueous sample containing 0.1% formic acid (FA), it is possible to detect 100-200 fmol of peptide, whereas +/-10 fmol can be detected in a sample containing 5% FA and 25% DMSO (10 microL injections). 相似文献
130.
Catharanthus roseus is still the only source for the powerful antitumour drugs vinblastine and vincristine. Some other pharmaceutical compounds
from this plant, ajmalicine and serpentine are also of economical importance. Although C. roseus has been studied extensively and was subject of numerous publications, a full characterization of its alkaloid pathway is
not yet achieved. Here we review some of the recent work done on this plant. Most of the work focussed on early steps of the
pathway, particularly the discovery of the 2-C-methyl-d-erythritol 4-phosphate (MEP)-pathway leading to terpenoids. Both mevalonate and MEP pathways are utilized by plants with
apparent cross-talk between them across different compartments. Many genes of the early steps in Catharanthus alkaloid pathway have been cloned and overexpressed to improve the biosynthesis. Research on the late steps in the pathway
resulted in cloning of several genes. Enzymes and genes involved in indole alkaloid biosynthesis and various aspects of their
localization and regulation are discussed. Much progress has been made at alkaloid regulatory level. Feeding precursors, growth
regulators treatments and metabolic engineering are good tools to increase productivity of terpenoid indole alkaloids. But
still our knowledge of the late steps in the Catharanthus alkaloid pathway and the genes involved is limited. 相似文献