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  1. Article: Natural Products from Microalgae with Potential against Alzheimer’s Disease: Sulfolipids Are Potent Glutaminyl Cyclase Inhibitors

    Wessjohann, Ludger A.

    Marine drugs, 14(11): 203

    2016  

    Abstract: In recent years, many new enzymes, like glutaminyl cyclase (QC), could be associated with pathophysiological processes and represent targets for many diseases, so that enzyme-inhibiting properties of natural substances are becoming increasingly important. ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract In recent years, many new enzymes, like glutaminyl cyclase (QC), could be associated with pathophysiological processes and represent targets for many diseases, so that enzyme-inhibiting properties of natural substances are becoming increasingly important. In different studies, the pathophysiology connection of QC to various diseases including Alzheimer’s disease (AD) was described. Algae are known for the ability to synthesize complex and highly-diverse compounds with specific enzyme inhibition properties. Therefore, we screened different algae species for the presence of QC inhibiting metabolites using a new “Reverse Metabolomics” technique including an Activity-correlation Analysis (AcorA), which is based on the correlation of bioactivities to mass spectral data with the aid of mathematic informatics deconvolution. Thus, three QC inhibiting compounds from microalgae belonging to the family of sulfolipids were identified. The compounds showed a QC inhibition of 81% and 76% at concentrations of 0.25 mg/mL and 0.025 mg/mL, respectively. Thus, for the first time, sulfolipids are identified as QC inhibiting compounds and possess substructures with the required pharmacophore qualities. They represent a new lead structure for QC inhibitors.
    Keywords AD ; Scenedesmus sp. ; glutaminyl cyclase (QC) inhibitor ; microalgae ; natural product ; sulfolipids ; reverse metabolomics
    Language English
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  2. Article: Synthesis of antibacterial 1,3-diyne-linked peptoids from an Ugi-4CR/Glaser coupling approach

    Wessjohann, Ludger A.

    Beilstein journal of organic chemistry, 11: 25–30

    2015  

    Abstract: A library of ten 1,3-diyne-linked peptoids has been synthesized through an Ugi four-component reaction (U-4CR) followed by a copper-catalysed alkyne homocoupling (Glaser reaction). The short and chemoselective reaction sequence allows generating diverse ( ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract A library of ten 1,3-diyne-linked peptoids has been synthesized through an Ugi four-component reaction (U-4CR) followed by a copper-catalysed alkyne homocoupling (Glaser reaction). The short and chemoselective reaction sequence allows generating diverse (pseudo) dimeric peptoids. A combinatorial version allows the one-pot preparation of, e.g., six-compound-libraries of homo- and heterodimers verified by ESI-MS and HPLC. In a preliminary evaluation, some compounds display moderate activity against the Gram-positive bacterium Bacillus subtilis.
    Keywords Ugi reaction ; combinatorial ; antibacterial ; diynes ; homodimerization ; multicomponent reactions ; peptoids
    Language English
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  3. Article: Hydrogen peroxide – production, fate and role in redox signaling of tumor cells

    Wessjohann, Ludger A.

    Cell communication and signaling, 13: 39

    2015  

    Abstract: Hydrogen peroxide (H2O2) is involved in various signal transduction pathways and cell fate decisions. The mechanism of the so called “redox signaling” includes the H2O2-mediated reversible oxidation of redox sensitive cysteine residues in enzymes and ... ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract Hydrogen peroxide (H2O2) is involved in various signal transduction pathways and cell fate decisions. The mechanism of the so called “redox signaling” includes the H2O2-mediated reversible oxidation of redox sensitive cysteine residues in enzymes and transcription factors thereby altering their activities. Depending on its intracellular concentration and localization, H2O2 exhibits either pro- or anti-apoptotic activities. In comparison to normal cells, cancer cells are characterized by an increased H2O2 production rate and an impaired redox balance thereby affecting the microenvironment as well as the anti-tumoral immune response. This article reviews the current knowledge about the intracellular production of H2O2 along with redox signaling pathways mediating either the growth or apoptosis of tumor cells. In addition it will be discussed how the targeting of H2O2-linked sources and/or signaling components involved in tumor progression and survival might lead to novel therapeutic targets.
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  4. Article: Protease-inhibiting, molecular modeling and antimicrobial activities of extracts and constituents from Helichrysum foetidum and Helichrysum mechowianum (compositae)

    Wessjohann, Ludger A.

    Chemistry central journal, 9:32

    2015  

    Abstract: BACKGROUND: Helichrysum species are used extensively for stress-related ailments and as dressings for wounds normally encountered in circumcision rites, bruises, cuts and sores. It has been reported that Helichysum species are used to relief abdominal ... ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract BACKGROUND: Helichrysum species are used extensively for stress-related ailments and as dressings for wounds normally encountered in circumcision rites, bruises, cuts and sores. It has been reported that Helichysum species are used to relief abdominal pain, heart burn, cough, cold, wounds, female sterility, menstrual pain. Results: From the extracts of Helichrysum foetidum (L.) Moench, six known compounds were isolated and identified. They were 7, 4′-dihydroxy-5-methoxy-flavanone (1), 6′-methoxy-2′,4, 4′-trihydroxychalcone (2), 6′-methoxy-2′,4-dihydroxychalcone -4′-O-β-D-glucoside (3), apigenin (4), apigenin-7-O-β-D-glucoside (5), kaur-16-en-18-oic acid (6) while two known compounds 3,5,7-trihydroxy-8-methoxyflavone (12), 4,5-dicaffeoyl quinic acid (13) together with a mixture of phytosterol were isolated from the methanol extract of Helichrysum mechowianum Klatt. All the compounds were characterized by spectroscopic and mass spectrometric methods, and by comparison with literature data. Both extracts and all the isolates were screened for the protease inhibition, antibacterial and antifungal activities. In addition, the phytochemical profiles of both species were investigated by ESI-MS experiments. CONCLUSIONS: These results showed that the protease inhibition assay of H. foetidum could be mainly attributed to the constituents of flavonoids glycosides (3, 5) while the compound (13) from H. mechowianum contributes to the stomach protecting effects. In addition, among the antibacterial and antifungal activities of all the isolates, compound (6) was found to possess a potent inhibitor effect against the tested microorganisms. The heterogeneity of the genus is also reflected in its phytochemical diversity. The differential bioactivities and determined constituents support the traditional use of the species. Molecular modelling was carried out by computing selected descriptors related to drug absorption, distribution, metabolism, excretion and toxicity (ADMET).
    Keywords Compositae ; Antimicrobial ; ESI-MS ; Helichrysum foetidum ; Helichysum mechowianum ; Protease inhibition assay
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  5. Article: Consecutive isocyanide-based multicomponent reactions: synthesis of cyclic pentadepsipeptoids

    Wessjohann, Ludger A.

    Beilstein journal of organic chemistry, 10: 1017–1022

    2014  

    Abstract: The synthesis of six cyclic depsipeptoids inspired by the natural depsipeptide sansalvamide A is described. An efficient and fast synthetic strategy was developed using a combination of consecutive isocyanide-based multicomponent reactions (Ugi and ... ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract The synthesis of six cyclic depsipeptoids inspired by the natural depsipeptide sansalvamide A is described. An efficient and fast synthetic strategy was developed using a combination of consecutive isocyanide-based multicomponent reactions (Ugi and Passerini reactions). This methodology can be used to access a variety of cyclic oligodepsipeptoids.
    Keywords Passerini reaction ; Ugi reaction ; depsipeptoids ; multicomponent reactions ; sansalvamide A
    Language English
    Document type Article
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  6. Article: Unequivocal glycyrrhizin isomer determination and comparative in vitro bioactivities of root extracts in four Glycyrrhiza species

    Porzel, Andrea / Wessjohann, Ludger A.

    Journal of advanced research, 6(1): 99-104

    2014  

    Abstract: Glycyrrhiza glabra, commonly known as licorice, is a popular herbal supplement used for the treatment of chronic inflammatory conditions and as sweetener in the food industry. This species contains a myriad of phytochemicals including the major saponin ... ...

    Institution Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract Glycyrrhiza glabra, commonly known as licorice, is a popular herbal supplement used for the treatment of chronic inflammatory conditions and as sweetener in the food industry. This species contains a myriad of phytochemicals including the major saponin glycoside glycyrrhizin (G) of Glycyrrhetinic acid (GA) aglycone. In this study, 2D-ROESY NMR technique was successfully applied for distinguishing 18α and 18β glycyrrhetinic acid (GA). ROESY spectra acquired from G. glabra, Glycyrrhiza uralensis and Glycyrrhiza inflata crude extracts revealed the presence of G in its β-form. Anti-inflammatory activity of four Glycyrrhiza species, G, glabra, G. uralensis, G. inflata, and G. echinata roots was assessed against COX-1 inhibition revealing that phenolics rather than glycyrrhizin are biologically active in this assay. G. inflata exhibits a strong cytotoxic effect against PC3 and HT29 cells lines, whereas other species are inactive. This study presents an effective NMR method for G isomer assignment in licorice extracts that does not require any preliminary chromatography or any other purification step.
    Keywords Glycyrrhizin ; G. glabra ; G. inflata ; G. uralensis ; Licorice ; ROESY
    Language English
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  7. Article: Effect of Oxylipins, Terpenoid Precursors and Wounding on Soft Corals’ Secondary Metabolism as Analyzed via UPLC/MS and Chemometrics

    Westphal, Hildegard / Wessjohann, Ludger A. / Meyer, Achim

    Molecules, 22(12):2195

    2017  

    Abstract: The effect of three oxylipin analogues, a terpenoid intermediate and wounding on the secondary metabolism of the soft corals Sarcophyton glaucum and Lobophyton pauciflorum was assessed. Examined oxylipins included prostaglandin (PG-E1), methyl jasmonate ( ...

    Institution Leibniz-Zentrum für Marine Tropenforschung
    Leibniz-Institut für Pflanzenbiochemie (Halle (Saale))
    Abstract The effect of three oxylipin analogues, a terpenoid intermediate and wounding on the secondary metabolism of the soft corals Sarcophyton glaucum and Lobophyton pauciflorum was assessed. Examined oxylipins included prostaglandin (PG-E1), methyl jasmonate (MeJA), and arachidonic acid (AA) in addition to the diterpene precursor geranylgeranylpyrophosphate (GGP). Post-elicitation, metabolites were extracted from coral heads and analyzed via UPLC-MS followed by multivariate data analyses. Both supervised and unsupervised data analyses were used for sample classification. Multivariate data analysis revealed clear segregation of PG-E1 and MeJA elicited S. glaucum at 24 and 48 h post elicitation from other elicitor samples and unelicited control group. PG-E1 was found more effective in upregulating S. glaucum terpene/sterol levels compared to MeJA. Metabolites showing upregulation in S. glaucum include campestene-triol and a cembranoid, detected at ca. 30- and 2-fold higher levels compared to unelicited corals. Such an elicitation effect was less notable in the other coral species L. pauciflorum, suggesting a differential oxylipin response in soft corals. Compared to MeJA and PG, no elicitation effect was observed for GGP, AA or wounding on the metabolism of either coral species.
    Keywords cembranoids ; chemometrics ; oxylipins ; soft corals ; sterols
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  8. Article: Cytotoxic Effects of Sarcophyton sp. Soft Corals—Is There a Correlation to Their NMR Fingerprints?

    Meyer, Achim / Porzel, Andrea / Westphal, Hildegard / Wessjohann, Ludger A.

    Marine drugs, 15(7):211

    2017  

    Abstract: Sarcophyton sp. soft corals are rich in cembranoid diterpenes, which represent the main chemical defense of corals against their natural predators in addition to their myriad biological effects in humans. Quantitative NMR (qNMR) was applied for assessing ...

    Institution Leibniz-Zentrum für Marine Tropenforschung
    Abstract Sarcophyton sp. soft corals are rich in cembranoid diterpenes, which represent the main chemical defense of corals against their natural predators in addition to their myriad biological effects in humans. Quantitative NMR (qNMR) was applied for assessing the diterpene variation in 16 soft coral specimens in the context of their genotype, origin, and growing habitat. qNMR revealed high diterpene levels in Sarcophyton sp. compared to Sinularia and Lobophyton, with (ent)sarcophines as major components (17–100 µg/mg) of the coral tissues. Multivariate data analysis was employed to classify samples based on the quantified level of diterpenes, and compared to the untargeted NMR approach. Results revealed that qNMR provided a stronger classification model of Sarcophyton sp. than untargeted NMR fingerprinting. Additionally, cytotoxicity of soft coral crude extracts was assessed against androgen-dependent prostate cancer cell lines (PC3) and androgen-independent colon cancer cell lines (HT-29), with IC50 values ranging from 10–60 µg/mL. No obvious correlation between the extracts’ IC50 values and their diterpene levels was found using either Spearman or Pearson correlations. This suggests that this type of bioactivity may not be easily predicted by NMR metabolomics in soft corals, or is not strongly correlated to measured diterpene levels.
    Keywords metabolomics ; cembranoids ; Sarcophyton ; quantitative nuclear magnetic resonance (qNMR) ; terpenoids
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  9. Article ; Online: Assessment of metabolome diversity in black and white pepper in response to autoclaving using MS- and NMR-based metabolomics and in relation to its remote and direct antimicrobial effects against food-borne pathogens.

    Baky, Mostafa H / Kamal, Islam M / Wessjohann, Ludger A / Farag, Mohamed A

    RSC advances

    2024  Volume 14, Issue 15, Page(s) 10799–10813

    Abstract: ... Piper ... ...

    Abstract Piper nigrum
    Language English
    Publishing date 2024-04-03
    Publishing country England
    Document type Journal Article
    ISSN 2046-2069
    ISSN (online) 2046-2069
    DOI 10.1039/d4ra00100a
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: In Vitro Anticancer Screening and Preliminary Mechanistic Study of A-Ring Substituted Anthraquinone Derivatives.

    Morgan, Ibrahim / Wessjohann, Ludger A / Kaluđerović, Goran N

    Cells

    2022  Volume 11, Issue 1

    Abstract: Anthraquinone derivatives exhibit various biological activities, e.g., antifungal, antibacterial and in vitro antiviral activities. They are naturally produced in many fungal and plant families such as Rhamnaceae or Fabaceae. Furthermore, they were found ...

    Abstract Anthraquinone derivatives exhibit various biological activities, e.g., antifungal, antibacterial and in vitro antiviral activities. They are naturally produced in many fungal and plant families such as Rhamnaceae or Fabaceae. Furthermore, they were found to have anticancer activity, exemplified by mitoxantrone and pixantrone, and many are well known redox-active compounds. In this study, various nature inspired synthetic anthraquinone derivatives were tested against colon, prostate, liver and cervical cancer cell lines. Most of the compounds exhibit anticancer effects against all cell lines, therefore the compounds were further studied to determine their IC
    MeSH term(s) Adenine/analogs & derivatives ; Adenine/pharmacology ; Anthraquinones/chemistry ; Anthraquinones/pharmacology ; Apoptosis/drug effects ; Autophagy/drug effects ; Caspases/metabolism ; Cell Line, Tumor ; Cell Survival/drug effects ; DNA Topoisomerases/metabolism ; Drug Screening Assays, Antitumor ; Emodin/chemistry ; Emodin/pharmacology ; Enzyme Activation/drug effects ; G2 Phase/drug effects ; Humans ; Inhibitory Concentration 50 ; Mitosis/drug effects
    Chemical Substances Anthraquinones ; 3-methyladenine (5142-23-4) ; aloe emodin (C8IYT9CR7C) ; Caspases (EC 3.4.22.-) ; DNA Topoisomerases (EC 5.99.1.-) ; Adenine (JAC85A2161) ; Emodin (KA46RNI6HN)
    Language English
    Publishing date 2022-01-05
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2661518-6
    ISSN 2073-4409 ; 2073-4409
    ISSN (online) 2073-4409
    ISSN 2073-4409
    DOI 10.3390/cells11010168
    Database MEDical Literature Analysis and Retrieval System OnLINE

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