Wyniki wyszukiwania - Biblioteka Nauki

1

Improved high-performance liquid chromatography-DAD method for the simultaneous analysis of quercetin and kaempferol in the stems of Cissus quadrangularis Linn

100%

Thakur A. K. , Jain V. , Hingorani L. , Laddha K. S.

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tom Vol. 21, no. 1

95-103

EN

A simple, rapid, and specific reversed-phase HPLC method with DAD detection has been used for analysis of two flavonoids, quercetin and kaempferol, in Cissus quadrangularis Linn. The flavonoids were well resolved within 10 min, and quantification was achieved, on an endcapped C 18 column at 370 nm with acetonitrile-phosphate buffer (pH 3.4, adjusted with glacial acetic acid) 60:40 (v/v) as isocratic mobile phase at a flow rate of 1.0 mL min -1. The method was validated for limit of detection, limit of quantification, linearity, precision, accuracy, and recovery. Linearity was demonstrated over the range 0.75 to 10 µg mL -1 for quercetin and 1.0 to 10 µg mL -1 for kaempferol with good correlation coefficients ( r 2 > 0.998). Detection limits were 0.075 and 0.10 µg mL -1 for quercetin and kaempferol respectively. Recovery was 98.0-105.3% for quercetin and 95.0-101.1% for kaempferol. The method was successfully applied to analysis of two flavonoids in four samples of Cissus quadrangularis Linn.

2

Method of quercetin extraction from dry scales of onion

100%

Horbowicz M.

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tom 57

3

EF-1alpha is a target site for inhibitory effect of quercetin in the peptide elongation process

100%

Marcinkiewicz C. , Galasinski W. , Gindzienski A.

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tom 42

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nr 3

EN

The effect of quercetin (3,3',4',5,7-pentahydroxyflavone) on the polypeptide elongation system isolated from rat liver cells, was investigated. Quercetin inhibited [ 4C]leucine incorporation into proteins in vitro and the inhibitory effect is being directed towards the elongation factor eEF-1, but not to eEF-2 and ribosomes. Quercetin was found to form a complex with EF-la, which was inactive in GTP-dependent binding to ribosomes. It can be suggested that quercetin can block the total or the part of the domain of EF-la structure that is responsible for formation of the ternary complex EF-la-GTP-i14C]Phe-tRNA and therefore preventing formation of the quaternary complex with ribosomes.

4

Effect of sucrose as an elicitor in increasing quercetin-3-O-rhamnoside (quercitrin) content of chrysanthemum (Chrysanthemum morifolium Ramat) callus culture based on harvest time differences

88%

Setiawati T. , Arofah A. N. , Nurzaman M. , Anisa A. , Mutaqin A. Z. , Hasan R.

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nr 3

5

Inhibitory effect of quercetin on glycolysis in blood platelets

88%

Tomasiak M.

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nr 1

6

VALIDATION OF HEPATOPROTECTIVE USE OF POLYGONUM PERFOLIATUM EXTRACT AGAINST PARACETAMOL INDUCED TOXICITY IN WISTAR RATS

75%

Saleem M. , Mushtaq M. F. , Akhtar M. F. , Saleem A. , Zahid S. , Sharif A. , Akhtar B. , Dar E. , Ullah M. , Badshah M.

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nr 2

283-289

EN

The liver as a vital body organ is adversely affected by hazardous chemicals and drugs. Paracetamol widely used as analgesic and antipyretic drug produces severe hepatotoxicity at high doses. Present study was designed to investigate the hepatoprotective activity of Polygonum perfoliatum L. used on folklore basis. Aqueous methanolic extract of the plant was prepared. Preliminary phytochemical and HPLC analyses were carried out to identify and quantify chemical constituents respectively. For hepatoprotective activity, Wistar rats were divided into six groups as normal control, standard (silymarin) control, negative control and extract treated groups i.e., 125, 250 and 500 mg/kg/day per oral. Paracetamol was administered orally, following seven days of previously stated therapy. Biochemical parameters of hepatotoxicity such as serum glutamic pyruvate transaminase (SGPT), serum glutamic oxaloacetate transaminase (SGOT), alkaline phosphatase (ALP) and total bilirubin were measured in all groups. Histopathological evaluation of liver was also carried out. Benzoic acid, chlorogenic acid, gallic acid, m-coumaric acid, quercetin and vitamin E were detected in the plant extract through HPLC. The hepatoprotective effect of 500 mg/kg/day therapy was more pronounced than 125 and 250 mg/kg dose. However, the effect of plant extract was less pronounced than standard silymarin therapy. It can be concluded that the plant extract possessed significant hepatoprotective activity that may be attributed to quercetin, benzoic acid, gallic acid and vitamin E present in it.

7

Mitochondrial function of human preadipocytes may be modulated by antioxidants quercetin and beta carotene, and exogenous free fatty acids

75%

Sliwa A. , Goralska J. , Awsiuk M. , Czech U. , Gruca A. , Kiec-Wilk B. , Knapp A. , Dembinska-Kiec A.

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tom 61

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nr Suppl.1

8

Antioxidant Activity and Mechanism in Flower of Hylocereus Undatus (Haw.) Britt. Et Rose

75%

Li X. , Gao Y. , Han W. , Lin J. , Hu Q. , Chen D.

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nr 1

9

Changes of the flavonols content in onion during the vegetation period and storage

75%

Horbowicz M.

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tom 50

10

The effect of quercetin on induction of apoptosis

75%

Rzymowska J. , Gawron A. , Pawlikowska-Pawlega B. , Jakubowicz-Gil J. , Wojcierowski J.

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nr 2

11

The influence of quercetin on some biochemical parameters in rats exposed to environmental contamination with fluorine compounds

75%

Czerny B. , Put A. , Mysliwiec Z. , Juzyszyn Z.

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nr 3

EN

Male Wistar rats were exposed for 3 and 6 months to NH4F in a toxicological chamber. Some animals received sodium salts of quercetin sulfonic acids at a dose of 5 or 20 mg/kg body weight. It was found that quercetin alleviates biochemical changes in the liver caused by ammonium fluoride, in particular concerning enzyme activities and lipid metabolism.

12

Effects of quercetin and verapamil on membrane potential in the liverwort Conocephalum conicum

75%

Pawlikowska-Pawlega B. , Trebacz K. , Krol E. , Gawron A.

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nr 1

13

Potencjalne wykorzystanie substancji pochodzenia roślinnego w leczeniu choroby Alzheimera

63%

Pypno D. , Zdrojewicz Z.

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tom 11

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nr 3

289-294

EN

Alzheimer’s disease is the most common neurodegenerative condition in elderly people which is characterised by progressing dementia. Patients present weaker episodic memory, attention and orientation disorders as well as cognitive and language dysfunctions. General atrophy of the brain, primarily the hippocampus and frontal cortex, is observed. Microscopically, senile/neuritic plaques composed of, inter alia, β-amyloid concretions, are found. The degeneration of the basal forebrain causes decreased activity of acetylcholine and choline acetyltransferase. Alzheimer’s disease is treated mostly by symptomatic measures since there are no drugs able to slow down or reverse the changes. The main medications include: donepezil, rivastigmine, galantamine and memantine. The prevalence increases from 3% at the age of 65 to 47% at the age of 85. The prognosis is poor; the disease progresses and causes death in a few years, mostly due to complications. Various tests on the effects and potential application of substances of plant origin in treating Alzheimer’s disease have been conducted. Quercetin found in apples, resveratrol in grapes and red wine as well as rosmarinic acid and tanshinones in salvia exhibit a protective action against the toxicity of β-amyloid concretions. Water extract from peach seeds might be a valuable inhibitor of acetylcholinesterase while vegetables possess only anti-butyrylcholinesterase activity. The purpose of this paper is the analysis whether the substances found in plants might be potentially useful in treating Alzheimer’s disease.

PL

Choroba Alzheimera to najczęściej występujące u osób w podeszłym wieku schorzenie neurodegeneracyjne, którego istotą jest postępujące otępienie. U pacjentów obserwuje się upośledzenie pamięci epizodycznej, zaburzenia uwagi, orientacji, funkcji językowych i poznawczych. Stwierdza się uogólniony zanik mózgu, głównie hipokampa i kory czołowej. Mikroskopowo widoczne są płytki starcze, zbudowane m.in. ze złogów β-amyloidu, i zwyrodnienie neurofibrylarne. W wyniku zwyrodnienia podstawnej części przodomózgowia zmniejszają się zawartość acetylocholiny i aktywność acetylotransferazy cholinowej. Postępowanie w przypadku choroby Alzheimera jest głównie objawowe, gdyż nie ma leków hamujących postęp choroby ani odwracających istniejące zmiany. Stosowane są głównie: donepezil, rywastygmina, galantamina i memantyna. Chorobowość zwiększa się z 3% u osób w wieku 65 lat do 47% u osób w wieku 85 lat. Rokowanie jest złe, choroba postępuje, a pacjenci umierają w ciągu kilku lat, głównie z powodu powikłań. Przeprowadzono liczne badania nad działaniem substancji zawartych w roślinach oraz ich potencjalnym wykorzystaniem w terapii choroby Alzheimera. Kwercetyna zawarta w jabłkach, resweratrol obecny w winogronach i czerwonym winie oraz kwas rozmarynowy i tanszinony w szałwii przez różne mechanizmy działają ochronnie wobec toksyczności złogów β-amyloidu. Ekstrakt wodny z pestek brzoskwini zwyczajnej może być użytecznym inhibitorem acetylocholinesterazy, zaś warzywa wykazują jedynie aktywność antybutyrylocholinesterazową. Celem pracy jest przegląd dostępnych badań w poszukiwaniu odpowiedzi na pytanie, czy substancje zawarte w roślinach mogą być stosowane w leczeniu choroby Alzheimera.

14

Quercetin in association with moderate exercise training attenuates injuries induced by experimental diabetes in sciatic nerves

63%

Chis I. C. , Clichici A. , Nagy A. L. , Oros A. , Catoi C. , Clichici S.

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nr 6

15

Synthesis of quercetin-functionalized silver nanoparticles by rapid one-pot approach

63%

Pandian S. R. K. , Kunjiappan S. , Ravishankar V. , Sundarapandian V.

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nr 1