Wyniki wyszukiwania - Biblioteka Nauki

1

Isolation of gallic acid and methyl gallate from folium Toonea Sinensis and validated method for their quantitation using LC-based technologies

100%

Shen Y. , Yang H. , Xia G. , Wang J. , Cai B. , Jia X.

Acta Chromatographica

|

2013

|

tom Vol. 25, no. 4

687--701

EN

Silica-gel column chromatography and preparative reversed-phase high-performance liquid chromatography (RP-HPLC) were sequentially employed for the isolation of two antioxidants including gallic acid and methyl gallate from Folium Toonea Sinensis. An RP-HPLC-UV method was then developed and validated to rapidly determine their content in this herb with ethyl gallate as internal standard. The quantitation was performed on an XBridge Shield RP18 column (150 mm × 4.6 mm, 5 μm) under 40°C. The mobile phase consisting of acetonitrile and 0.1% formic acid aqueous solution was driven at 1.0 mL min -1 under gradient elution, and 270 nm was selected to monitor the separation. To evaluate the fitness for purpose of the method and to investigate the difference in the content of analytes among different samples, the leaves collected from five production sites were analyzed. The newly established method is suitable for routine analysis of gallic acid and methyl gallate in the herb and, hence, can assist in its quality assessment. It was also found that not only the content of two antioxidants but also the ratio varied significantly among different geographical origins. In addition, three samples from Yantai, Zumadian, and Zhenjiang were distinguished as they have a much higher content ratio than the other two.

2

Double-edged sword behaviour of gallic acid and its interaction with peroxidases in human microvascular endothelial cell culture (HMEC-1). Antioxidant and pro-oxidant effects

100%

Serrano J. , Cipak A. , Boada J. , Gonzalo H. , Cacabelos D. , Cassanye A. , Pamplona R. , Zarkovic N. , Portero-Otin M.

Acta Biochimica Polonica

|

2010

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tom 57

|

nr 2

193-198

EN

A previous report from our group had shown in vitro a direct interaction between peroxidases and dietary antioxidants at physiological concentrations, where in the absence of H2O2, the antioxidants could serve as oxidizing substrates for the peroxidases. However, the physiological relevance of those findings had not been evaluated. The main objective of this study was to determine whether the oxidizing products produced in the interaction between peroxidase and gallic acid at a physiological concentration of 1 µM may promote cell death or survival in a human microvascular endothelial cell line (HMEC-1). Our findings suggested that gallic acid may show a double-edged sword behaviour, since in the absence of H2O2 it may have a pro-oxidant effect which may promote cell injury (evidenced by LDH, Crystal Violet and calcein AM viability/citotoxicity assays), while in the presence of H2O2, gallic acid may act as an antioxidant inhibiting oxidative species produced in the peroxidase cycle of peroxidases. These observations were confirmed with several oxidative stress biomarkers and the evaluation of the activation of cell survival pathways like AKT and MAPK/ERK.

3

Synthesis and properties of model humic substances derived from gallic acid

100%

Slawinska D. , Polewski K. , Rolewski P. , Slawinski J.

International Agrophysics

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2007

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tom 21

|

nr 2

4

Mikrobiologiczny rozkład kwasu galusowego

86%

Wojcieszyńska D. , Guzik U. , Jaroszek P.

Inżynieria i Ochrona Środowiska

|

2009

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tom T. 12, nr 3

173-184

PL

Kwas galusowy należy do grupy roślinnych związków zwanych polifenolami. Związek ten występuje w roślinach w postaci wolnej i związanej w estrach. Rozkład GA zachodzi zarówno w tlenowych, jak i beztlenowych warunkach, a główną rolę w jego degradacji odgrywają mikroorganizmy. Kluczowymi enzymami tlenowej degradacji GA są, należące do oksygenaz, dioksygenazy rozszczepiające, katalizujące rozpad pierścienia aromatycznego z udziałem tlenu. Tlenowa degradacja kwasu galusowego u bakterii może zachodzić szlakiem meta, inicjowanym przez dioksygenazę galusanową i 4,5-dioksygenazę protokatechową, lub szlakiem orto, zapoczątkowanym aktywnością 3,4-dioksygenazy protokatechowej. Produktami rozkładu GA stwierdzonymi u Pseudomonas putida są pirogronian i szczawiooctan. Rozkład GA z udziałem tlenu powiązany jest również ze szlakiem ß-ketoadypinowym kwasu protokatechowego, którego końcowymi produktami są acetylo-CoA i bursztynylo-CoA. Stwierdzono także obecność tlenowej degradacji GA u grzybów. Głównymi związkami przejściowymi beztlenowej degradacji GA są floroglucyna oraz rezorcyna. Kluczowym produktem przejściowym w degradacji kwasu galusowego poprzez floroglucynę jest 3-hydroksy-5-ketoheksanian (HOHN). Rezorcyna, drugi produkt przejściowy beztlenowej degradacji GA, powstaje z floroglucyny i pirogalolu przez dehydroksylację. Związek ten może ulegać następnie redukcji z udziałem reduktazy rezorcynowej lub hydrolizie do kwasu 5-keto-2-heksenowego.

EN

Gallic acid (3,4,5-trihydroxybenzoic acid) is widely distributed throughout the plant kingdom. It is present in almost all plants. High gallic acid contents can be found in gallnuts, grapes, tea, hops and oak bark. According to its biochemical properties gallic acid is an industrially important chemical used as an antioxidant in food, cosmetics and pharmaceutical industries. It possesses a lot of potential therapeutic properties including anti-cancer and antimicrobial ones. The gallic acid is readily utilized by oxidative breakdown to simple aliphatic acids that are metabolized through the citric acid cycle. Although different aerobic pathways for the aromatic acids biodegradation are known they usually involve the formation of protocatechuate as a common intermediate. Protocatechuate may be cleaved by protocatechuate 3.4- dioxygenase [EC 1.13.11.3], which catalyzes the intradiol addition of molecular oxygen and forms 2-pyrone-4,6-dicarboxylic acid as well as protocatechuate 4.5-dioxygenase [1.13.11.8] that catalyzes extradiol addition of molecular oxygen result in 4-carboxy-2-hydroxy-cis,cis-muconic semialdehyde formation. Another mechanism of gallic acid degradation is observed in fungi. In Aspergillus niger gallic acid is oxidatively cleaved by an oxygenase to unstable tricarboxylic intermediate decarboxylated by an oxidative decarboxylase to cis-aconitic acid enter the citric acid cycle. Aspergillus flavus degrades gallic acid to oxaloacetic acid and finally pyruvic acid through the tricarboxylic acid intermediates. Different mechanisms of anaerobic breakdown of gallic acid are known. At the first step of its degradation gallate is decarboxylated to 1,2,3-trihydroxybenzene, which is isomerized to phloroglucinol by pyrogallol-phloroglucinol isomerase and then reduced to dihydrophloroglucinol by phloroglucinol reductase. In the next step dihydrophloroglucinol is converted to 3-hydroxy-5-oxohexanonic acid (HOHN) by dihydrophloroglucinol hydrolase. Then, HOHN may be degraded through different pathways. The first one is its conversion to 3,5-dioxohexanoate (triacetate) by HOHN dehydrogenase and ultimately to three molecules of acetyl-CoA via triacetyl-CoA by the sequential enzymatic reactions catalyzed by triacetyl-CoA transferase, triacetate-ketothiolase, acetoacetyl-CoA-ketothiolase, phosphotransacetylase and acetate kinase. In methanogenic conditions HONH-CoA is transformed to butyrate or acetate, which are finally degraded to methane and carbon dioxide.

5

Comparative effects of selected plant polyphenols, gallic acid and epigallocatechin gallate, on matrix metalloproteinases activity in multidrug resistant MCF7/DOX breast cancer cells

86%

Nowakowska A. , Tarasiuk J.

Acta Biochimica Polonica

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2016

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tom 63

|

nr 3

571-575

EN

The aim of the study was to investigate the effect of selected polyphenols: gallic acid (GA) and epigallocatechin gallate (EGCG) on matrix metalloproteinase (MMP-2 and MMP-9) activity in multidrug resistant (MDR) human breast adenocarcinoma cells: MCF7/DOX cells and obtained recently in our laboratory MCF7/DOX500 cells by the permanent selection of MCF7/DOX cells with 500 nM doxorubicin (DOX). The activity of MMP-2 and MMP-9 and the effect of studied polyphenols on these matrix proteases were examined by gelatin zymography assays. We have found that the activity of MMP-2 and MMP-9 significantly increased in resistant MCF7/DOX and MCF7/DOX500 cells whereas they were not detected in sensitive MCF7 cells. It was also observed that GA (30, 60, 100 and 120 µM) and EGCG (5, 10 and 20 µM) caused a comparable concentration-dependent inhibition of MMP-2 and MMP-9 activity in MCF7/DOX and MCF7/DOX500 cells. Control experiments confirmed that examined compounds in these ranges of concentration did not affect the cell growth of MCF7/DOX and MCF7/DOX500 sublines (80-100% of control cell growth was observed in the presence of studied polyphenols).

6

Analysis of gallic acid and ellagic acid in leaves of Elaeagnus angustifolia L. from different habitats and times in Xinjiang by HPLC with cluster analysis

86%

Sun Y. , Liu J. , Bayertai , Tang S. , Zhou X.

Acta Chromatographica

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2021

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tom Vol. 33, no. 2

195--201

EN

Objective: To determine the levels of gallic acid and ellagic acid by using high-performance liquid chromatography (HPLC) with R software hierarchical cluster analysisin Elaeagnus angustifolia L. gathered from different locations in Xinjiang. Methods: A chromatographic column Diamonsil C18 with a size of 4.63250 mm and 5 mm was used with methanol as A and 0.1% phosphoric acid aqueous solution as B as the mobile phase. The flow rate was 1 mL/min for the gradient elution and the injection volume was 5 mL. HPLC was performed with a detection wavelength of 260 nm and chromatographic column of 35 8C. In addition, R software hierarchical clustering method was used for studying the levels of gallic acid and ellagic acid in E. angustifolia L. from 10 areas. Results: Gallic acid and ellagic acid showed a good linear relationship between 7.375 and 236 mg/mL with a correlation coefficient of 0.9999, and between 3.625 and 116 mg/mL with a correlation coefficient of 0.9999 respectively. The average recovery values were 103.98 and 101.57%, and the Relative Standard Deviation (RSD) values were 1.92 and 1.47%. Conclusion: Differences in the levels of gallic acid and ellagic acid in E. angustifolia L. leaves from different areas in Xinjiang showed that both were the highest in Kuitun.

7

Physicochemical parameters effect on biosynthesis and properties of copper nanoparticles

86%

Pawlowska A. , Kazmierczak M. , Sadowski Z.

Physicochemical Problems of Mineral Processing

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2019

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tom Vol. 55, iss. 6

1460--1466

EN

Plant extract obtained from green tea was used for the synthesis of nanoparticles under anaerobic and aerobic conditions at various ratios of the copper solution to the extract used. The smallest nanoparticles were obtained at a ratio of 1:10. The nanoparticles showed the maximum negative value of the zeta potential around pH 6. An increase in the temperature of reaction caused a decrease in the negative zeta potential value. Synthesis under nitrogen atmosphere favours the formation of smaller copper nanoparticles.

8

Encapsulation of gallic acid with acid-modified low dextrose equivalent potato starch using spray- and freeze-drying techniques

86%

Sepelevs I. , Stepanova V. , Galoburda R.

Polish Journal of Food and Nutrition Sciences

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2018

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tom 68

|

nr 3

EN

The main objective of the present study was to investigate the effect of spray- and freeze-drying techniques on the microencapsulation of a gallic acid compound using the acid-hydrolyzed low dextrose equivalent potato starch as a wall material. During the experiment, it was possible to achieve encapsulation efficiency of 70–84% for the freeze-dried and 65–79% for spray-dried samples, without statistically signifi cant difference (P>0.05) in the encapsulation efficiency between the mentioned methods. Spray-dried samples formed spherical capsules with a higher number of micropores. Meanwhile, freeze-dried samples were shapeless, exposed larger pore volume (from 2.4×10–3 to 9.5×10–3 cm3 /g against 1.2×10–3 4.9×10–3 cm3 /g; analyzed by Barrett-Joyner-Halenda method) and overall higher surface area (0.632–1.225 m²/g against 0.472–1.296 m²/g; analyzed by Barrett-Joyner- -Halenda method). Due to this fact, more gallic acid molecules were exposed to environmental factors and can be counted as losses. In addition, freeze-dried samples demonstrated lower water activity than spray-dried samples (0.075±0.014 against 0.178±0.008). Results showed that it is not practical to use freeze-drying for modelling encapsulation for food industry without a special necessity for protection of easily degradable chemical compounds. The present work makes a basis for the future studies of the microencapsulated phenolics application in food production.

9

The antioxidative activity of some plant polyphenols

86%

Sroka Z. , Rzadkowska-Bodalska H.

Biophysics of Membrane Transport

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1994

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tom 12

|

nr 2

10

Phenolic constituents of fireweed (Epilobium angustifolium L.) herb

72%

El-Ansari M. A. , Weglarz Z. , Ali Kawashty S. , Skiba A.

Annals of Warsaw Agricultural University. Horticulture (Landscape Architecture)

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2002

|

tom 23

11

Wpływ obróbki ultradźwiękowej na stabilność i aktywność antyoksydacyjną kwasu galusowego

72%

Kobus Z. , Rydzak L. , Wilczyński K. , Nadulski R. , Guz T. , Zawiślak K.

Przemysł Chemiczny

|

2018

|

tom T. 97, nr 5

724--727

PL

Przedstawiono wyniki wpływu obróbki ultradźwiękowej na stabilność i aktywność antyoksydacyjną kwasu galusowego. Do badań wykorzystano cztery roztwory kwasu galusowego: o stężeniu 0,2 mg/mL i 1,0 mg/mL, sporządzone na bazie wody i metanolu. Obróbkę ultradźwiękową przeprowadzono, używając procesora ultradźwiękowego (Sonic VCX 750). Doświadczenie prowadzono przez 0, 10 i 30 min, wykorzystując pole akustyczne o częstotliwości 20 kHz oraz natężeniu 21 W/cm2 i 38 W/cm2. Nie stwierdzono statystycznie istotnego wpływu ultradźwięków na stabilność wodnych roztworów kwasu galusowego. Zaobserwowano nieznaczną, ale statystycznie istotną degradację metanolowych roztworów kwasu galusowego.

EN

Four gallic acid solns. (0.2 and 1.0 mg/mL) prepd. on the basis of H2O or MeOH were subjected to ultrasounds (frequency 20 kHz, intensity 21 or 38 W/cm2, time 0–30 min). A slight but statistically significant degrdn. of gallic acid was obsd. only for its MeOH solns., esp. for the concn. of 0.2 mg/mL and the treatment time of 30 min. Ultrasounds did not change the oxidative activity of the tested solns.

12

Oenothera paradoxa defatted seeds extract containing pentagalloylglucose and procyanidins potentiates the cytotoxicity of vincristine

72%

Jaszewska E. , Kosmider A. , Kiss A. K. , Naruszewicz M.

Journal of Physiology and Pharmacology

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2010

|

tom 61

|

nr 5

13

Determination of chlorogenic and gallic acids by UPLC-MS/MS

72%

Gryszczynska A. , Opala B. , Lowicki Z. , Krajewska-Patan A. , Buchwald W. , Czerny B. , Mielcarek S. , Boron D. , Bogacz A. , Mrozikiewicz P. M.

Herba Polonica

|

2013

|

tom 59

|

nr 1

EN

The aim of our study were qualitative and quantitative analyses of two polyphenolic acids: chlorogenic and gallic acids. These compounds were determined in two species of Rhodiola: R. kirilowii and R. rosea. After collecting plants, aqueous and hydroalcoholic extracts were prepared. In order to identify analysed polyphenolic compounds ultra performance liquid chromatography - tandem mass spectrometry (UPLC-MS/MS, Waters) was used. Gallic acid is commonly found in the roots of these plants. Aqueous extract in both species is a rich source of gallic acid. The UPLC-MS/MS studies allow to use this analytical method for determination of polyphenolic acids accordance with the requirements of ICH. Chromatographic method developed by our team is more precise then previously published.

PL

W Instytucie Włókien Naturalnych i Roślin Zielarskich podjęto badania mające na celu opracowanie metody detekcji kwasu chlorogenowego oraz galusowego za pomocą ultrasprawnej chromatografii cieczowej sprzężonej z tandemowym spektrometrem mas (UPLCMS/ MS, Waters). Badaniom poddano dwa gatunki różnica: Rhodiola kirilowii oraz R. rosea. Rośliny zostały wyhodowane w uprawie gruntowej w Instytucie. Przeprowadzona walidacja metody pozwoliła na jej wykorzystanie w ocenie zawartości kwasu chlorogenowego oraz galusowego w badanych roślinach, ponieważ zawartość analizowanych związków zależna jest zarówno od gatunku jak i warunków uprawy.

14

Simultaneous determination of gallic acid, protocatechuic acid, catechin, epicatechin, quercetin and kaempferol in Chinese chestnut (Castanea mollissima blume) kernel by high-performance liquid chromatography with diode array detection

72%

Wang T. , Yang Y. D. , Du B. , Yu S. , Hou W. L.

Acta Chromatographica

|

2014

|

tom Vol. 26, no. 3

539--550

EN

Chestnut exhibits anti-inflammatory, styptic, anti-diarrhea, and analgestic effects as a traditional Chinese medicine. There is increasing evidence that shows that the consumption of chestnuts has become more important in human nutrition due to the health benefits provided by the antioxidants. The phenolic compounds are responsible for major bioactivities, such as anti-tumor and anti-oxidation. A high-performance liquid chromatography (HPLC) method with diode array detection (DAD) was established for the simultaneous determination of six phenolic compounds (gallic acid, GA; protocatechuic acid, PR; catechin, CA; epicatechin, EP; quercetin, QU; kaempferol, KA) in Chinese chestnut (Castanea mollissima blume) kernel. The sample followed by separation on Eclipse XDB-C18 column (150 × 4.6 mm, id., 5 μm) with gradient elution of methanol-1.0% acetate acid solution as a mobile phase, at a temperature of 30°C, under the ratio of 1.2 mL min-1, with 5 μL injection volume, and multi-wavelength synthesis was used with DAD. The correlation coefficients were larger than 0.999, the recoveries were 97.58% for GA, 100.41% for PA, 96.23% for CA, 101.38% for QU, 99.15% for EP, and 98.60% for KA, relative standard deviation (RSD) were 1.04% for GA, 1.21% for PA, 1.09% for CA, 1.19% for QU, 1.06% for EP, and 1.20% for KA. This method was applied for the determination of phenolics in chestnut kernel and was found to be fast, sensitive, and suitable.

15

Wytwarzanie kwasu galusowego w reaktorze membranowym

72%

Poherecki R. , Galwas-Zakrzewska M.

Inżynieria Chemiczna i Procesowa

|

2001

|

tom T. 22, z. 3D

1163--1168

PL

Tanaza (acylo hydrolaza tanin) katalizuje reakcję hydrolizy wiązań estrowych występujących w gallotaninach. Prowadzi to do uwolnienia kwasu galusowego. Reakcja enzymatyczna jest hamowana produktem. Badano reaktor membranowy z unieruchomionym enzymem. Moduł ze spiralną membraną stanowił separacyjną część układu. Opracowano model opisujący pracę układu i wyznaczono wydajność wytwarzania kwasu galusowego w zależności od warunków prowadzenia procesu.

EN

Tannase (tannin acyl hydrolase) catalyses the hydrolysis of ester bonds in hydrolysable gallotannins releasing glucose and gallic acid. The product inhibits the enzymatic reaction. A membrane reactor with immobilized enzyme was studied. A spiral membrane module represents the separation part. A mathematical model describing the process was developed. The productivity of process was determined.

16

Determining polyphenolic antioxidant distributions between the oil, water and interfacial regions of model food emulsions

72%

Bravo-Diaz C. , Losada-Barreiro S. , Paz V. S. , Pavia-Martins F.

Polish Journal of Food and Nutrition Sciences

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2011

|

tom 61

|

nr Suppl.1

17

Phytochemical composition and antifungal effectiveness of Phoenix dactylifera L. rachis extracts

72%

Abdelkhalek A. , Abdelwahab E. A. , Elalem S. F. , Al-Askar A. A. , Kowalczewski P. Ł. , Behiry S.

Polish Journal of Chemical Technology

|

2024

|

tom Vol. 26, nr 3

76--84

EN

The present study appraised the inhibitory role of ethanol (PDEE) and ethyl acetate (PDEAE) extracts of Phoenix dactylifera L. against three molecularly identified fungi: Fusarium oxysporum, Botrytis cinerea, and Rhizoctonia solani. HPLC analysis revealed that gallic acid was the major phenolic compound in both extracts: (PDEE: 1721.90 μg/g) and (PDEAE: 101.53 μg/g). The major flavonoids in PDEE are rutin, kaempferol, and quercetin, whereas PDEAE contains kaempferol, naringenin, and quercetin. The GC-MS showed 11-octadecenoic acid methyl ester (26.25%) is the highest compound in PDEE, while diisooctyl phthalate (18.82%) is the most important compound in PDEAE. At 50 μg/mL, the inhibition percentage of PDEAE initiated the highest growth inhibition of F. oxysporum (49.63%) and R. solani (71.43%). Meanwhile, PDEE at 200 μg/mL initiated an inhibition value of 77.78% for B. cinerea. As a result, PDEAE is considered more effective than PDEE in controlling the growth of selected isolates.

18

Efficiency of herb preparation and gallic acid in pig feeding

72%

Hanczakowska E. , Swiatkiewicz M. , Szewczyk A.

Annals of Animal Science

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2007

|

tom 07

|

nr 1

19

Accumulation of gallic and salicylic acid in winter triticale in response to aphid attack

72%

Chrzanowski G. , Ciepiela A. P. , Sempruch C. , Sprawka I. , Sytykiewicz H. , Czerniewicz P.

Herba Polonica

|

2002

|

tom 48

|

nr 4

EN

Gallic and salicylic acids were extracted with 60% methanol from the ears of two winter triticale cultivars (Dagro and Malno). Separation of phenolic acids was carried out in HPLC column - Eurospher RP-18 with use of KNAUER Maxi-Star K-1000 pump. Mixture of methanol-0.1 M KH₂PO₄ (4.5:5.5) was as mobile phase. Absorbance of analysed phenolic compounds was measured at 230 nm. Obtained results showed that content of gallic and salicylic acids was higher in winter triticale Malno than Dagro. Simultaneously, the increase of salicylic acid concentration was observed in the ears of Malno plants as a result of aphid feeding.

PL

Kwas galusowy i salicylowy ekstrahowano 60% metanolem z kłosów dwóch odmian pszenżyta ozimego (Dagro i Malno). Rozdział kwasów fenolowych przeprowadzono metodą chromatografii cieczowej (HPLC) z wykorzystaniem aparatu KNAUER Maxi-Star K-1000 na kolumnie Eurospher RP-18. Fazę ruchomą stanowiła mieszanina alkohol metylowy: 0,1 M KH₂PO₄ (4,5:5,5). Absorbancję oznaczanych związków fenolowych mierzono przy długości fali 230 nm. Stwierdzono, że pszenżyto ozime Malno odznaczało się wyższym stężeniem zarówno kwasu galusowego jak i salicylowego w porównaniu z odmianą Dagro. Jednocześnie wykazano wzrost stężenia kwasu salicylowego w kłosach odmiany Malno pod wpływem żerowania mszyc.

20

Double-edged sword behaviour of gallic acid and its interaction with peroxidases in human microvascular endothelial cell culture (HMEC-1). Antioxidant and pro-oxidant effects

58%

Serrano J. , Cipak A. , Boada J. , Gonzalo H. , Cacabelos D. , Cassanye A. , Pamplona R. , Zarkovic N. , Portero-Otin M.

|

tom 57

|

nr 2

EN

A previous report from our group had shown in vitro a direct interaction between peroxidases and dietary antioxidants at physiological concentrations, where in the absence of H2O2, the antioxidants could serve as oxidizing substrates for the peroxidases. However, the physiological relevance of those findings had not been evaluated. The main objective of this study was to determine whether the oxidizing products produced in the interaction between peroxidase and gallic acid at a physiological concentration of 1 μM may promote cell death or survival in a human microvascular endothelial cell line (HMEC-1). Our findings suggested that gallic acid may show a double-edged sword behaviour, since in the absence of H2O2 it may have a pro-oxidant effect which may promote cell injury (evidenced by LDH, Crystal Violet and calcein AM viability/citotoxicity assays), while in the presence of H2O2, gallic acid may act as an antioxidant inhibiting oxidative species produced in the peroxidase cycle of peroxidases. These observations were confirmed with several oxidative stress biomarkers and the evaluation of the activation of cell survival pathways like AKT and MAPK/ERK.