Unser 10. Leibniz Plant Biochemistry Symposium am 7. und 8. Mai war ein großer Erfolg. Thematisch ging es in diesem Jahr um neue Methoden und Forschungsansätze der Naturstoffchemie. Die exzellenten Vorträge über Wirkstoffe…
Omanische Heilpflanze im Fokus der Phytochemie IPB-Wissenschaftler und Partner aus Dhofar haben jüngst die omanische Heilpflanze Terminalia dhofarica unter die phytochemische Lupe genommen. Die Pflanze ist reich an…
Geschmack ist vorhersagbar: Mit FlavorMiner. FlavorMiner heißt das Tool, das IPB-Chemiker und Partner aus Kolumbien jüngst entwickelt haben. Das Programm kann, basierend auf maschinellem Lernen (KI), anhand der…
The Human Proteome Organization (HUPO) Proteomics Standards Initiative (PSI) has been successfully developing guidelines, data formats, and controlled vocabularies (CVs) for the proteomics community and other fields supported by mass spectrometry since its inception 20 years ago. Here we describe the general operation of the PSI, including its leadership, working groups, yearly workshops, and the document process by which proposals are thoroughly and publicly reviewed in order to be ratified as PSI standards. We briefly describe the current state of the many existing PSI standards, some of which remain the same as when originally developed, some of which have undergone subsequent revisions, and some of which have become obsolete. Then the set of proposals currently being developed are described, with an open call to the community for participation in the forging of the next generation of standards. Finally, we describe some synergies and collaborations with other organizations and look to the future in how the PSI will continue to promote the open sharing of data and thus accelerate the progress of the field of proteomics.
Publikation
de Moura, P. H. B.; de Sousa, A. A.; Porzel, A.; Wessjohann, L. A.; Leal, I. C. R.; Martins, R. C. C.;Characterization of antibacterial proanthocyanidins of Dalbergia monetaria, an amazonian medicinal plant, by UHPLC-HRMS/MSPlanta Med.86858– 866(2020)DOI: 10.1055/a-1170-8016
Dalbergia monetaria is an Amazonian plant whose bark is widely used to treat urinary tract infections. This paper describes a bio-guided study of ethanolic extracts from the bark and leaves of D. monetaria, in a search for metabolites active against human pathogenic bacteria. In vitro assays were performed against 10 bacterial strains, highlighting methicillin-sensitive Staphylococcus aureus and methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. Fractioning of the extracts was performed using instrumental and classical techniques, and samples were characterized by UHPLC-HRMS/MS. Ethyl acetate fractions from bark and leaves showed similar antibacterial activities. EAFB is enriched in isoflavone C-glucosides and EAFL enriched in proanthocyanidins. Subfractions from EAFL presented higher activity and showed a complex profile of proanthocyanidins constructed by (epi)-cassiaflavan and (epi)-catechin units, including dimers, trimers and tetramers. The fragmentation pattern emphasized the neutral loss of cassiaflavan units by quinone-methide fission. Fraction SL7-6, constituted by (ent)-cassiaflavan-(ent)-cassiaflavan-(epi)-catechin isomers, showed the lowest MIC against the S. aureus and P. aeruginosa with values corresponding to 64 and 32 µg/mL, respectively. Cassiaflavan-proanthocyanidins have not been found previously in another botanical genus, except in Cassia, and the traditional medicinal use of D. monetaria might be related to the antibacterial activity of proanthocyanidins characterized in the species.
Publikation
Jouda, J.-B.; Njoya, E. M.; Fobofou, S. A. T.; Zhou, Z. Y.; Qiang, Z.; Mbazoa, C. D.; Brandt, W.; Zhang, G.-l.; Wandji, J.; Wang, F.;Natural Polyketides Isolated from the Endophytic Fungus
Phomopsis sp. CAM212 with a Semisynthetic Derivative Downregulating
the ERK/IκBα Signaling PathwaysPlanta Med.861032-1042(2020)DOI: 10.1055/a-1212-2930
AbstractThree previously undescribed natural products, phomopsinin A – C
(1 – 3), together with three known compounds, namely,
cis-hydroxymellein (4), phomoxanthone A (5) and
cytochalasin L-696,474 (6), were isolated from the solid culture of
Phomopsis sp. CAM212, an endophytic fungus obtained from Garcinia
xanthochymus. Their structures were determined on the basis of
spectroscopic data, including IR, NMR, and MS. The absolute configurations of
1 and 2 were assigned by comparing their experimental and
calculated ECD spectra. Acetylation of compound 1 yielded 1a, a
new natural product derivative that was tested together with other isolated
compounds on lipopolysaccharide-stimulated RAW 264.7 cells. Cytochalasin
L-696,474 (6) was found to significantly inhibit nitric oxide production,
but was highly cytotoxic to the treated cells, whereas compound 1
slightly inhibited nitric oxide production, which was not significantly
different compared to lipopolysaccharide-treated cells. Remarkably, the
acetylated derivative of 1, compound 1a, significantly inhibited
nitric oxide production with an IC50 value of 14.8 µM and no
cytotoxic effect on treated cells, thereby showing the importance of the acetyl
group in the anti-inflammatory activity of 1a. The study of the mechanism
of action revealed that 1a decreases the expression of inducible nitric
oxide synthase, cyclooxygenase 2, and proinflammatory cytokine IL-6 without an
effect on IL-1β expression. Moreover, it was found that 1a exerts
its anti-inflammatory activity in lipopolysaccharide-stimulated RAW 264.7
macrophage cells by downregulating the activation of ERK1/2 and by preventing
the translocation of nuclear factor κB. Thus, derivatives of phomopsinin
A (1), such as compound 1a, could provide new anti-inflammatory
leads.
Publikation
Hussain, H.; Ziegler, J.; Mrestani, Y.; Neubert, R. H. H.;Studies of the Corneocytary Pathway Across the Stratum Corneum. Part I: Diffusion of Amino Acids Into the Isolated CorneocytesPharmazie74340-344(2019)DOI: 10.1691/ph.2019.8098
Amino acids (AAs), important constituents of natural moisturizing factors (NMFs) of the skin are decreased in diseased conditions such as psoriasis and atopic dermatitis. No study so far investigated the uptake of AAs into isolated corneocytes (COR). The present study was performed using 19 AAs, including taurine (TAU), to measure their amount diffused into the COR and binding of these AAs to keratin. Incubation of alanine, aspartic acid, asparagine, glutamine, glutamic acid, histidine, proline, serine and TAU with the isolated COR showed uptake after 24 h of 51.6, 95.4, 98.6, 94.1, 95.6, 90.1, 94.6, 72.9 and 57.8 %, respectively, into the COR but no binding with keratin. Uptake of TAU was validated by time dependent in-vitro diffusion models 'without COR and 'with COR'. The time dependent curve fitting showed that in in-vitro diffusion model 'without COR' there was no change in the total concentration of TAU until 72 hours, while in diffusion model 'with COR' the total conc. decreased to 37.8 % after 72 hours. The Pearson's correlation coefficient 'r' between the conc. curves of both in-vitro diffusion models was -0.54 that was an evidence of significant amount of TAU uptake by the COR. AAs as part of the NMFs have a great potential to be diffused into the COR. This property of the AAs can be employed in further dermatological research on diseased or aged skin conditions with NMFs deficiency.