The IPB has once again been recognized for its exemplary actions in terms of equal opportunity-oriented personnel and organizational policies and has received the TOTAL E-QUALITY certification for the…
The Plant Science Student Conference (PSSC) has been organised by students from the two Leibniz institutes, IPK and IPB, every year for the last 20 years. In this interview, Christina Wäsch (IPK) and…
Farag, M. A.; Otify, A.; Porzel, A.; Michel, C. G.; Elsayed, A.; Wessjohann, L. A.;Comparative metabolite profiling and fingerprinting of genus Passiflora leaves using a multiplex approach of UPLC-MS and NMR analyzed by chemometric toolsAnal. Bioanal. Chem.4083125-3143(2016)DOI: 10.1007/s00216-016-9376-4
Passiflora incarnata as well as some other Passiflora species are reported to possess anxiolytic and sedative activity and to treat various CNS disorders. The medicinal use of only a few Passiflora species has been scientifically verified. There are over 400 species in the Passiflora genus worldwide, most of which have been little characterized in terms of phytochemical or pharmacological properties. Herein, large-scale multi-targeted metabolic profiling and fingerprinting techniques were utilized to help gain a broader insight into Passiflora species leaves’ chemical composition. Nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) spectra of extracted components derived from 17 Passiflora accessions and from different geographical origins were analyzed using multivariate data analyses. A total of 78 metabolites were tentatively identified, that is, 20 C-flavonoids, 8 O-flavonoids, 21 C, O-flavonoids, 2 cyanogenic glycosides, and 23 fatty acid conjugates, of which several flavonoid conjugates are for the first time to be reported in Passiflora spp. To the best of our knowledge, this study provides the most complete map for secondary metabolite distribution within that genus. Major signals in 1H-NMR and MS spectra contributing to species discrimination were assigned to those of C-flavonoids including isovitexin-2″-O-xyloside, luteolin-C-deoxyhexoside-O-hexoside, schaftoside, isovitexin, and isoorientin. P. incarnata was found most enriched in C-flavonoids, justifying its use as an official drug within that genus. Compared to NMR, LC-MS was found more effective in sample classification based on genetic and/ or geographical origin as revealed from derived multivariate data analyses. Novel insight on metabolite candidates to mediate for Passiflora CNS sedative effects is also presented.
Publications
Greifenhagen, U.; Frolov, A.; Blüher, M.; Hoffmann, R.;Site-specific analysis of advanced glycation end products in plasma proteins of type 2 diabetes mellitus patientsAnal. Bioanal. Chem.4085557-5566(2016)DOI: 10.1007/s00216-016-9651-4
Advanced glycation end products (AGEs) are posttranslational modifications formed non-enzymatically from the reaction of carbohydrates and their degradation products with proteins. Accumulation of AGEs is associated with the progression of severe diabetic complications, for example, and elevated tissue levels of AGEs might even predict these pathologies. As AGE formation is often site-specific, mapping of these modification sites may reveal more sensitive and specific markers than the global tissue level. Here, 42 AGE modifications were identified in a bottom-up proteomic approach by tandem mass spectrometry, which corresponded to 36 sites in 22 high to medium abundant proteins in individual plasma samples obtained from type 2 diabetes mellitus (T2DM) patients with long disease duration (>10 years). Major modifications were glarg (11 modification sites) and carboxymethylation (5) of arginine and formylation (8), acetylation (7), and carboxymethylation (7) of lysine residues. Relative quantification of these sites in plasma samples obtained from normoglycemic individuals (n = 47) and patients with T2DM being newly diagnosed (n = 47) or of medium (2–5 years, n = 20) and long disease duration (>10 years, n = 20) did not reveal any significant differences.