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N O Kalinina - One of the best experts on this subject based on the ideXlab platform.
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plant...
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plants. The nanoparticles were characterized by TEM, absorbance spectroscopy, SAED, EELS, XPS, and DLS methods and were shown to contain mainly iron oxide and iron oxohydroxide. H. vulgare extracts produced amorphous iron oxide nanoparticles with diameters of up to 30 nm. These iron nanoparticles are intrinsically unstable and prone to aggregation; however, we rendered them stable in the long term by addition of 40 mM citrate buffer pH 3.0. In contrast, amorphous iron oxide nanoparticles (diameters of 10–40 nm) produced using R. acetosa extracts are highly stable. The total protein content and antioxidant capacity are similar for both extracts, but pH values differ (H. vulgare pH 5.8 vs R. acetosa pH 3.7). We suggest that the presence of organic acids (such oxalic or citric acids) plays an important role in the stabi...
Andreas Hensel - One of the best experts on this subject based on the ideXlab platform.
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hydroalkoholischer extrakt aus sauerampferkraut Rumex acetosa l zur prophylaxe von mundschleimhauterkrankungen und periodontitis hemmung der bakteriellen adhasion und zentraler virulenzfaktoren von porphyromonas gingivalis
Zeitschrift für Phytotherapie, 2016Co-Authors: Jana Schmuch, Sabine Beckert, Gesine Löhr, Thomas Beikler, Simone Brandt, Andreas HenselAbstract:Sauerampferkraut aus den oberirdischen Teilen von Rumex acetosa L. wird traditionell gegen entzundliche Erkrankungen der Mundhohle verwendet. Die vorliegende Studie untersuchte den Einfluss eines Proanthocyanidin-angereicherten hydroalkoholischen Extraktes (RA1) auf die Adhasion von Porphyromonas gingivalis , eines Bakteriums, welches ein zentraler Mitverursacher der chronischen und aggressiven Parodontitis darstellt. Ein weiteres Ziel der Untersuchungen war die Identifizierung von bioaktiven Leitstrukturen mit antiadhasiver Aktivitat und die Benennung der fur die antiadhasiven Effekte verantwortlichen molekularen Mechanismen. Der vollstandig quantifizierte Extrakt RA1 (5-15 µg/ml) reduzierte die bakterielle Adhasion von P. gingivalis an humanen KB-Mundschleimhautzellen in vitro dosisabhangig bis zu 90 %. Dies wurde sowohl in einem durchflusszytometrischen Test als auch mittels Konfokaler Laser Scanning Mikroskopie belegt. Die In-vitro -Datensatze konnten auch in einem In-situ -Modell an Buccalschleimhaut der Maus bestatigt werden. Die Kombination phytochemischer Methoden mit funktionellen Adhasionsassays identifizierte fur die aus RA1 isolierten Naturstoffen 1 bis 15 Epicatechin-3-O-gallat-(4β,8)-epicatechin-3’-O-gallat (syn. Procyanidin B2-di-gallat, Verbindung 8) als stark antiadhasives Proanthocyanidin, welches als funktionelle Leitsubstanz des Extraktes angesehen wird. Struktur-Wirkungsbeziehungen zeigten, dass eine mindestens einfache Galloylierung von Flavan-3-olen fur eine antiadhasive Wirkung notwendig ist. Die Aktivitat der Verbindungen wird durch Trihydroxylierung im B-Ring und durch Oligomerisierung weiter gesteigert. Als molekularer Angriffspunkt fur diese Wirkstoffe wurde der bakterielle Virulenzfaktor Arginin-Gingipain identifiziert, ein zentraler Virulenzfaktor von P. gingivalis , der neben der bakteriellen Adhasion des Pathogens an der Wirtszelle auch proteolytischen Abbau von Wirtsproteinen, Modulation der immunologischen Wirtsabwehr und Reifung weiterer bakterieller Virulenzfaktoren induziert. Aus diesen Untersuchungen zeigt sich ein ausreichendes Potenzial von Sauerampferextrakt zur weiteren praklinischen und klinischen Entwicklung zu zytoprotektiven Mundhygieneprodukten.
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Extract from Rumex acetosa L. for prophylaxis of periodontitis: Inhibition of bacterial in vitro adhesion and of gingipains of Porphyromonas gingivalis by epicatechin-3-O-(4β→8)-epicatechin-3-O-gallate (procyanidin-B2-di-gallate)
PLoS ONE, 2015Co-Authors: Jana Schmuch, Sabine Beckert, Gesine Löhr, Fabian Hermann, Thomas Beikler, Simone Brandt, Thomas J. Schmidt, Andreas HenselAbstract:BACKGROUND The aerial parts of Rumex acetosa L. have been used in traditional European medicine for inflammatory diseases of the mouth epithelial tissue. The following study aimed to investigate the influence of a proanthocyanidin-enriched extract from R. acetosa extract against the adhesion of Porphyromonas gingivalis (P. gingivalis), a pathogen strongly involved in chronic and aggressive periodontitis. A further goal was to define the bioactive lead structures responsible for a potential antiadhesive activity and to characterize the underlying molecular mechanisms of the antiadhesive effects. METHODOLOGY An extract of R. acetosa (RA1) with a defined mixture of flavan-3-ols, oligomeric proanthocyanidins and flavonoids, was used. Its impact on P. gingivalis adhesion to KB cells was studied by flow cytometry, confocal laser scanning microscopy and in situ adhesion assay using murine buccal tissue. RA1 and its compounds 1 to 15 were further investigated for additional effects on gingipain activity, hemagglutination and gene expression by RT-PCR. PRINCIPAL FINDINGS RA1 (5 to 15 μg/mL) reduced P. gingivalis adhesion in a dose-dependent manner to about 90%. Galloylated proanthocyanidins were confirmed to be responsible for this antiadhesive effect with epicatechin-3-O-gallate-(4β,8)-epicatechin-3'-O-gallate (syn. procyanidin B2-di-gallate) being the lead compound. Ungalloylated flavan-3-ols and oligomeric proanthocyanidins were inactive. RA1 and the galloylated proanthocyanidins strongly interact with the bacterial virulence factor Arg-gingipain, while the corresponding Lys-gingipain was hardly influenced. RA1 inhibited also hemagglutination. In silico docking studies indicated that epicatechin-3-O-gallate-(4β,8)-epicatechin-3'-O-gallate interacts with the active side of Arg-gingipain and hemaglutinin from P. gingivalis; the galloylation of the molecule seems to be responsible for fixation of the ligand to the protein. In conclusion, the proanthocyanidin-enriched extract RA1 and its main active constituent procyanidin B2-di-gallate protect cells from P. gingivalis infection by inhibiting bacterial adhesion to the host cell. RA1 and procyanidin B2-di-gallate appear to be promising candidates for future cytoprotective preparations for oral mouth care products.
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proanthocyanidin enriched extract of Rumex acetosa l inhibits the in vitro adhesion of porphyromonas gingivalis to kb cells and decreases the biofilm formation
Planta Medica, 2013Co-Authors: Jana Schmuch, K Koller, S Beckert, A Podbielski, Andreas HenselAbstract:Porphyromonas gingivalis is a gram-negative periodontal pathogen, which plays a significant role in the progression of chronic periodontitis and may even be involved in the development of other cardiovascular diseases. The first critical step for the initiation of periodontitis is the specific adhesion of bacteria to tissue cells. By forming complex biofilms, anaerobic bacteria as P. gingivalis evade the hosts immune defense. In contrast to conventional antibacterial therapy approaches, an acetone-water extract of Rumex acetosa L. (RA1) [1] was tested for in vitro antiadhesive activity on KB cells by flow cytometrie in order to initiate a development against the first step of the infection. Bacteria, preincubated with RA1 (100 µg/mL) showed 25% less adhesion to KB cells. By coincubating bacteria, KB cells and RA1 (10 µg/mL) a significant decrease of adhesion of 37% was observed. Structure-activity relationship of relevant polyphenols from RA1 indicated that proanthocyanidins are responsible for these effects. Especially epicatechin-3-O-gallate-(4β-> 8)-epicatechin-3-O-gallate (20µM: 61%; 30µM: 96% inhibition) significantly reduces the adhesion of P. gingivalis to KB cells. Epicatechin-3-O-gallat has a lower antiadhesive activity (20µM: 21%; 30µM: 25% inhibition). Non-galloylated flavan-3-ols had no effect. Besides the inhibition of bacterial adhesion, the influence of RA1 on the biofilm formation was investigated. We could detect a significant inhibition of biofilm formation, after staining the biofilm with crystal violet (RA1 100 µg/mL, 51% inhibition). Reference: [1] Bicker J, Petereit F, Hensel A (2009) Proanthocyanidins and a phloroglucinol derivative from Rumex acetosa L. Fitoterapia. 80(8); 483 – 95.
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proanthocyanidins and a phloroglucinol derivative from Rumex acetosa l
Fitoterapia, 2009Co-Authors: Jens Bicker, Frank Petereit, Andreas HenselAbstract:From the ethyl acetate soluble fraction of an acetone-water extract of the aerial parts of Rumex acetosa L. (Polygonaceae), a variety of monomeric flavan-3-ols (catechin, epicatechin, epicatechin-3-O-gallate), A- and B-type procyanidins and propelargonidins (15 dimers, 7 trimers, 2 tetramers) were isolated with 5 so far unknown natural products. Dimers: procyanidin B1, B2, B3, B4, B5, B7, A2, epiafzelechin-(4beta-->8)-epicatechin, epiafzelechin-(4beta-->8)-epicatechin-3-O-gallate (new natural product), epiafzelechin-(4beta-->6)-epicatechin-3-O-gallate (new natural product), epiafzelechin-3-O-gallate-(4beta-->8)-epicatechin-3-O-gallate, B2-3'-O-gallate, B2-3,3'-di-O-gallate, B5-3'-O-gallate, and B5-3,3'-di-O-gallate. Trimers: procyanidin C1, epiafzelechin-(4beta-->8)-epicatechin-(4beta-->8)-epicatechin (new natural product), epicatechin-(4beta-->8)-epicatechin-(4beta-->8)-catechin, cinnamtannin B1, cinnamtannin B1-3-O-gallate (new natural product), tentatively epicatechin-(2beta-->7, 4beta-->8)-epiafzelechin-(4alpha-->8)-epicatechin (new natural product), and epicatechin-3-O-gallate-(4beta-->8)-epicatechin-3-O-gallate-(4beta-->8)-epicatechin-3-O-gallate. Tetramers: procyanidin D1 and parameritannin A1. All compounds were elucidated by ESI-MS, CD spectra, 1D- and 2D-NMR experiments as free phenols or peracetylated derivatives and, in part, after partial acid-catalysed degradation with phloroglucinol. A more abundant proanthocyanidin polymer was also isolated, purified and its chemical composition studied by (13)C NMR. In addition a so far unknown phloroglucinolglycoside (1-O-beta-D-(2,4-dihydroxy-6-methoxyphenyl)-6-O-(4-hydroxy-3,5-dimethoxybenzoyl)-glucopyranoside) was isolated.
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Proanthocyanidins and a phloroglucinol derivative from Rumex acetosa L.
Fitoterapia, 2009Co-Authors: Jens Bicker, Frank Petereit, Andreas HenselAbstract:Abstract From the ethyl acetate soluble fraction of an acetone–water extract of the aerial parts of Rumex acetosa L. (Polygonaceae), a variety of monomeric flavan-3-ols (catechin, epicatechin, epicatechin-3-O-gallate), A- and B-type procyanidins and propelargonidins (15 dimers, 7 trimers, 2 tetramers) were isolated with 5 so far unknown natural products. Dimers : procyanidin B1, B2, B3, B4, B5, B7, A2, epiafzelechin-(4β→8)-epicatechin, epiafzelechin-(4β→8)-epicatechin-3- O -gallate (new natural product), epiafzelechin-(4β→6)-epicatechin-3- O -gallate (new natural product), epiafzelechin-3- O -gallate-(4β→8)-epicatechin-3- O -gallate, B2-3′- O -gallate, B2-3,3′-di- O -gallate, B5-3′- O -gallate, and B5-3,3′-di- O -gallate. Trimers : procyanidin C1, epiafzelechin-(4β→8)-epicatechin-(4β→8)-epicatechin (new natural product), epicatechin-(4β→8)-epicatechin-(4β→8)-catechin, cinnamtannin B1, cinnamtannin B1-3- O -gallate (new natural product), tentatively epicatechin-(2β→7, 4β→8)-epiafzelechin-(4α→8)-epicatechin (new natural product), and epicatechin-3- O -gallate-(4β→8)-epicatechin-3- O -gallate-(4β→8)-epicatechin-3- O -gallate. Tetramers : procyanidin D1 and parameritannin A1. All compounds were elucidated by ESI-MS, CD spectra, 1D- and 2D-NMR experiments as free phenols or peracetylated derivatives and, in part, after partial acid-catalysed degradation with phloroglucinol. A more abundant proanthocyanidin polymer was also isolated, purified and its chemical composition studied by 13 C NMR. In addition a so far unknown phloroglucinolglycoside (1- O -β- d -(2,4-dihydroxy-6-methoxyphenyl)-6- O -(4-hydroxy-3,5-dimethoxybenzoyl)-glucopyranoside) was isolated.
Valentin V Makarov - One of the best experts on this subject based on the ideXlab platform.
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plant...
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plants. The nanoparticles were characterized by TEM, absorbance spectroscopy, SAED, EELS, XPS, and DLS methods and were shown to contain mainly iron oxide and iron oxohydroxide. H. vulgare extracts produced amorphous iron oxide nanoparticles with diameters of up to 30 nm. These iron nanoparticles are intrinsically unstable and prone to aggregation; however, we rendered them stable in the long term by addition of 40 mM citrate buffer pH 3.0. In contrast, amorphous iron oxide nanoparticles (diameters of 10–40 nm) produced using R. acetosa extracts are highly stable. The total protein content and antioxidant capacity are similar for both extracts, but pH values differ (H. vulgare pH 5.8 vs R. acetosa pH 3.7). We suggest that the presence of organic acids (such oxalic or citric acids) plays an important role in the stabi...
Michael Taliansky - One of the best experts on this subject based on the ideXlab platform.
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plant...
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plants. The nanoparticles were characterized by TEM, absorbance spectroscopy, SAED, EELS, XPS, and DLS methods and were shown to contain mainly iron oxide and iron oxohydroxide. H. vulgare extracts produced amorphous iron oxide nanoparticles with diameters of up to 30 nm. These iron nanoparticles are intrinsically unstable and prone to aggregation; however, we rendered them stable in the long term by addition of 40 mM citrate buffer pH 3.0. In contrast, amorphous iron oxide nanoparticles (diameters of 10–40 nm) produced using R. acetosa extracts are highly stable. The total protein content and antioxidant capacity are similar for both extracts, but pH values differ (H. vulgare pH 5.8 vs R. acetosa pH 3.7). We suggest that the presence of organic acids (such oxalic or citric acids) plays an important role in the stabi...
I V Yaminsky - One of the best experts on this subject based on the ideXlab platform.
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plant...
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biosynthesis of stable iron oxide nanoparticles in aqueous extracts of hordeum vulgare and Rumex acetosa plants
Langmuir, 2014Co-Authors: Valentin V Makarov, S S Makarova, Andrew J Love, O V Sinitsyna, Anna O Dudnik, I V Yaminsky, Michael Taliansky, N O KalininaAbstract:We report the synthesis and characterization of amorphous iron oxide nanoparticles from iron salts in aqueous extracts of monocotyledonous (Hordeum vulgare) and dicotyledonous (Rumex acetosa) plants. The nanoparticles were characterized by TEM, absorbance spectroscopy, SAED, EELS, XPS, and DLS methods and were shown to contain mainly iron oxide and iron oxohydroxide. H. vulgare extracts produced amorphous iron oxide nanoparticles with diameters of up to 30 nm. These iron nanoparticles are intrinsically unstable and prone to aggregation; however, we rendered them stable in the long term by addition of 40 mM citrate buffer pH 3.0. In contrast, amorphous iron oxide nanoparticles (diameters of 10–40 nm) produced using R. acetosa extracts are highly stable. The total protein content and antioxidant capacity are similar for both extracts, but pH values differ (H. vulgare pH 5.8 vs R. acetosa pH 3.7). We suggest that the presence of organic acids (such oxalic or citric acids) plays an important role in the stabi...
