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EN
The purpose of the research was to study the effect of the quercetin-Ferrum complex on the synthesis of plastid pigments and secondary metabolites in berry crops. In the research, biotechnological, physiological, biochemical and statistical methods were used. The ability of quercetin, which is one of the most common flavonol aglycons, to create a chelated complex with Fe2+ and regulate physiological processes associated with oxidation-reduction reactions, synthesis of pigments and metal enzymes when being a supplement of nutrient medium is shown. With the addition of quercetin-Ferrum complex with a fraction of Fe2+ in a concentration equivalent to the base nutrient media composition optimized for the cultivation of berry crops in vitro, regenerated plants showed a sufficiently high regeneration capacity. Based on the indicators of the content of chlorophylls and carotenoids in leaves, the physiological availability of Ferrum in the quercetin-Ferrum complex was established. The concentration of chlorophylls a and b in raspberry and strawberry leaves increased by 20−25%, and the content of carotenoids increased by 30−40%. On the contrary, in black currant, the content of chlorophyll a in leaves decreased by 18−20% and chlorophyll b by almost 75%. It was found that quercetin is a biologically active phenolic chelating agent capable of chemically binding Fe2+ ions and participating in the regulation of growth processes, in particular in the induction of callusogenesis. Metal-flavonol complex is advisable to use in micro clonal reproduction of plants sensitive to oxidative stress in conditions of Fe2+ ions deficiency under the condition of individual selection of the components of the chelate complex and adjusting its concentration in the nutrient medium.
EN
Purpose: Nucleolin is a multifactorial protein, having a significant role in chromatin remodelling, mRNA stability, ribosome biogenesis, stemness, angiogenesis, etc., thus, it is potential therapeutic target in cancer. The purpose of this paper is to study porous silicon (pSi) nanocarrier-based natural drug delivery system targeting dysregulated nucleolin expression for cancer therapeutics. Design/methodology/approach: Quercetin was loaded in pre-synthesized and characterized pSi nanoparticles, and release kinetics was studied. The study compared the inhibitory concentration (IC50) of quercetin, synthetic drug doxorubicin, and quercetin-loaded pSi nanoparticles. Further, mRNA expression of a target gene, nucleolin, was tested with a quercetin treated breast cancer cell line (MCF-7). Findings: Quercetin-loaded pSi nanoparticles followed first-order release kinetics. IC50 was determined at concentrations of 312 nM, 160 μM, and 50 μM against doxorubicin, quercetin, and quercetin-loaded pSi nanoparticles, respectively. The results further indicated 16-fold downregulation of nucleolin mRNA expression after 48h of quercetin treatment of exponentially growing MCF-7 cells. Research limitations/implications: Whether pSi nanoparticle loaded quercetin can significantly downregulate nucleolin protein expression and its impact on apoptosis, cell proliferation, and angiogenic pathways need further investigation. Practical implications: The practical application of the proposed nanocarrier-based drug delivery system potentially lays out a path for developing targeted therapy against nucleolin-dysregulated cancer using natural products to minimize the side effects of conventional chemotherapeutic drugs. Originality/value: Inhibition of nucleolin and nucleolin regulated pathways using natural compounds and its targeted delivery with nanocarrier is not yet done.
3
Content available Optical sensor of flavonoids based on liquid crystal
EN
In order to solve the problems associated with the express registration of the presence of biologically active substances in callus biomass, we propose the use of cholesteric liquid crystal (CLC) with a spiral structure as a material of a sensitive element of optical sensor of flavonoids. Cholesteric liquid crystal BLO62 is proposed to use as a sensitive element. Spectral characteristics of alcohol solutions of flavonoids (20%, 40%, 70% and 90%) were obtained. The interaction of CLC with quercetin was analyzed. The scheme of the primary information signal converter is developed in which the current from the photodetector is transmitted to the developed signal converter. The device is implemented with the common use Atmega 328 microcontroller manufactured by Atmel. Speciality of this structural scheme is its flexibility and versatility, which makes it easy to reconfigure the parameters of the firmware for the registration of various types of investigated mediums.
PL
Aby rozwiązać problemy związane z szybką analizą obecności substancji biologicznie czynnych w biomasie kalusa, proponujemy zastosowanie materiałów ciekłokrystalicznych o spiralnej strukturze supramolekularnej jako wrażliwego elementu czujnika optycznego flawonoidów. Proponuje się stosowanie cholesterycznego ciekłego kryształu BLO62 jako wrażliwego elementu. Uzyskano charakterystykę spektralną roztworów alkoholowych flawonoidów (20%, 40%, 70% i 90%). Przeanalizowano interakcję cholesterycznego ciekłego kryształu z kwercetyną. Opracowano schemat pierwotnego przetwornika sygnału, w którym prąd z fotodetektora jest przesyłany do opracowanego przetwornika sygnałów. Urządzenie jest realizowane na bazie mikrokontrolera Atmega32 Atmega 328. Cechą tego schematu strukturalnego jest jego elastyczność i wszechstronność, co ułatwia rekonfigurację parametrów oprogramowania do rejestracji różnych typów badanych substancji.
PL
Brak uniwersalnych leków o aktywności przeciwnowotworowej powoduje, że obecnie wiele badań skupia się poszukiwaniu nowych związków chemicznych o aktywności antyoksydacyjnej i cytotoksycznej. W praktyce klinicznej stosuje się wiele terapeutyków, ale ich toksyczne działania uboczne, takie jak zahamowanie czynności szpiku zmuszają naukowców do syntezy leków o zredukowanym działaniu niepożądanym. Kwercetyna jest flawonoidem, który sam w sobie wykazuje aktywność przeciwnowotworową, a dodatkowo jej struktura umożliwia łatwe tworzenie związków chelatowych z metalami. Kompleksy związków bioaktywnych i jonów metali często wykazują silne właściwości cytotoksyczne i przeciwnowotworowe. Dokonano przeglądu literatury podsumowującej dotychczasowe badania aktywności biologicznej kompleksów kwercetyny z metalami na wybrane linie komórkowe.
EN
A review with 59 refs.
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.
EN
An ultrasensitive and rapid method for the determination of epicatechin, rutin, and quercetin was developed using capillary zone electrophoresis with on-line chemiluminescence detection. Under the optimal conditions, the analytes were baseline separated within 12 min. The limits of detection in turn were 0.60 pg mL-1 for epicatechin, 0.50 pg mL-1 for rutin, and 1.0 pg mL-1 for quercetin. The developed method was an easy and reliable method of determining these analytes concentrations in tea, extract Ginkgo biloba, and rutin tablet, demonstrating the feasibility and reliability of the proposed method.
EN
Fabrics made from wool and cotton were dyed with eucalyptus leaf extract, rutin, querecetin and tannin dyes by the pad-dry technique. In this experiment, ferrous sulfate was used as a mordant. Te dyeing properties were evaluated by measuring K/S values and CIELAB. Te different fastness properties were also evaluated. Te efect of dyes at diferent concentration levels with respect to their colour strength was also studied.
PL
Od kilku lat na świecie trwają badania składników roślin owadożernych wykazujących atrakcyjne właściwości biologicznie czynne, tj. działanie przeciwbakteryjne, przeciwgrzybowe, antyoksydacyjne, a być może, także, przeciwnowotworowe. Pozyskiwanie substancji biologicznie aktywnych z materiału naturalnego, na drodze hodowli in vitro a następnie ekstrakcji i rozdzielania jest bardziej korzystne pod względem ekonomicznym, niż ich wytwarzanie metodami syntezy chemicznej, która w wielu przypadkach składa się z wielu etapów, a wypadkowa efektywności jest często niezadowalajca. W pracy zaprezentowano wyniki badań dotyczących opracowania najkorzystniejszych warunków rozdzielania oraz identyfikacji składników ekstraktów roślin owadożernych z czterech roślin rodziny Droseraceae, tzn., Drosera binata, Drosera capensis, Drosera aliciae oraz Dionea muscipula. Badania polegały na zaprojektowaniu optymalnego układu chromatograficznego oraz optymalnych warunków rozdzielania pozwalających w sposób możliwie jak najbardziej selektywny rozdzielić składniki z grupy naftochinonów oraz flawonoidów. Wykorzystano techniki kolumnowej wysokosprawnej chromatografii cieczowej, w odwróconych układach faz (RPHPLC), Porównano wyniki badań uzyskane z zastosowaniem elucji gradientowej. Za każdym razem stosowano przepływ zwrotny eluentu w kolumnie. Stosowanie elucji gradientowej jest celowe w badaniach składu metabolicznego roślin, identyfikacji oraz oznaczania zawartości składników w ekstraktach, a także w kontroli jakości i standaryzacji materiału zielarskiego.
EN
For several years have been carried out researches of chemical compounds with attractive biological activity (antimicrobial, antifungal, antioxidant and anticancer activity) founded in insectivorous plants. Production of plant metabolites from in vitro cultures by procedures consisting of the extraction methods and separation techniques is economically more advantageous, than classic methods of chemical synthesis, which are consisted of many steps, which final efficiency is unsatisfactory. A developed most favorable conditions for separation and identification of the components of extracts of four plants from Droseraceae: Drosera aliciae, Dionea muscipula, Drosera binata and Drosera capensis are presented in the paper. The optimal conditions of the chromatographic system provide a selective separation of naphthoquinones and flavonoids from the samples of plant extracts. Column chromatography techniques in reversed phase conditions were used in the researches. The paper presents a comparison of separations made in different chromatographic systems with gradient elution. After every separation the direction of the eluent flow in the column was inversed. Application of gradient elution is significant in researches for identification of the compounds and quantitative determination of plant metabolites, as well as for the quality control and standardization of natural herbal materials
PL
Badania nad opracowywaniem nowej metodyki rozdzielania składników o skomplikowanej budowie chemicznej z mieszanin o złożonym składzie pochodzenia naturalnego z wykorzystaniem kolumnowej chromatografii cieczowej ze względu na szereg czynników są w większości przypadków bardzo kosztowne. Dlatego w celu wstępnego doboru warunków rozdzielania korzystne jest stosowanie cienkowarstwowej chromatografii cieczowej (ang. Thin Layer Chromatography - TLC). Relatywnie mniejsza ilość zużytych eluentów, prostota i łatwość wykonania, a także nieskomplikowana aparatura dowodzi temu, że na etapie optymalizacji składu eluentu chromatografia cienkowarstwowa jest techniką najkorzystniejszą. TLC umożliwia także równoległe prowadzenie rozdzielania dużej liczby różniących się składem mieszanin w jednym układzie chromatograficznym w tym samym czasie. W pracy przedstawiono wyniki badań retencji dla eluentów wieloskładnikowych w odwróconym układzie faz. Analiza otrzymanych danych pozwoliła wyselekcjonować składniki eluentu o korzystnych parametrach retencyjnych, które zostaną następnie wykorzystane do rozdzielania składników metanolowych ekstraktów roślin owadożernych z zastosowaniem techniki kolumnowej chromatografii cieczowej.
EN
A development of the methodology for separation of components with complex chemical structure from natural origin complicated mixtures by column liquid chromatography techniques in most cases is very expensive. Therefore to obtain the consumption of the chemicals on a lower level, a thin layer chromatography as a main separation technique should be used in preselection studies of the eluent composition. In addition, the simplicity of the procedure and equipment are another advantages of TLC. A separation process of a few different mixtures can be proceeded on a one plate in the same time. The possibility to executing the orthogonal separation without any sophisticated equipment is another advantage of TLC technique. In the paper the results of separation of plant extracts by RP-TLC with different composition of the eluents are presented. Analysis of retention data allowed to select components of the eluent with favorable retention parameters, which can be used in the future for separation of this type of plant extracts by column liquid chromatography techniques.
EN
A HPLC-DAD method for simultaneous analysis of five flavonoids (rutin, quercitrin, quercetin, kaempferol, and isorhamnetin) in diabetic rat plasma has been developed and validated. Separation of the five flavonoids was accomplished on a C 18 column (250 mm × 4.6 mm i.d., 5-µm particle) and detection was performed at 350 nm. The best resolution was achieved with a methanol-0.1% formic acid gradient at a flow rate of 1.0 mL min −1 . The correlation coefficients for all the calibration plots ( r > 0.999) showed linearity was good over the range tested. The relative standard deviation of the method was less than 7% and 10% for intra- and inter-day assays, and average recovery was between 77.2 and 99.2%. Sensitivity was high and detection limits were between 0.006 and 0.02 µg mL −1 . The method has been successfully used to determine drug concentrations in diabetic rat plasma samples and the pharmacokinetics of the drugs.
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.
12
Content available remote HPLC monitoring of the microsomal stability of rutin and quercetin
EN
Reversed-phase HPLC has been used to monitor the concentration of the two major Chamomile components rutin and quercetin during rat liver microsomal treatment. The possibility of microsomal oxidative metabolism or stability of these two components was examined using a guard-column without any clean-up. The concentration of quercetin decreased when exposed to rat liver microsomal media whereas the rutin concentration did not change significantly over one hour of treatment.
EN
Polymorphism is one of the most important and amazing phenomenon in structural chemistry. The knowledge of this phenomenon is crucial both in experimental sciences (e.g.: chemistry, physics and crystallography) and in industry - especially in pharmaceutical industry. It is well known, that polymorphic forms of therapeutic compounds differ in their bioavailability - e.g. the rate of dissolution and equilibrium solubility. In extreme cases, one polymorph may be a medicine whilst the second may be very dangerous or even poisonous. In this light, the possibility to distinguish the desirable form of compound from the useless form, seems to be very important. In our article, some problems concerning the investigation of polymorphism phenomenon by applications of solid-state NMR are presented. The possibilities of current NMR techniques in searching of polymorphism as well as the practical aspects and applications are presented and discussed.
EN
Flavonoids (derivatives of 2-phenylo-y-benzopyrone) are a large group of biologically active plant products. As a common component of daily nutrition, flavonoids can modulate many biological processes. Therapeutic properties of flavonoids have been well known for many years. Originally, the object of interest was medicinal plants. The papers by Szent-Gyorgy in the thirties of the 20-th century aroused interest in flavonoids. Szent-Gyorgy revealed that a lemon compound belonging to flavonoids - hesperidin has a synergic effect with Vitamin C and prevents scurvy. Quercetin (3,5,7,3',4'-pentahydroxyflavone) and morin (3,5,7,2',4'-pentahydroxyflavone), Fig. 1, are the most widespread flavonoids. Due to their properties these compounds find application in therapy as viral antigens, bactericide and antitumor agents. Owing to a convenient position of oxygen in the 5C-OH and 4C=O as well as 3C-OH and 4C=O groups, morin and quercetin form chelate complexes with ions of p-, d- and f-electron metals. Some researchers think, that biological activity of flavonoids is connected with their complexation capacity. Therapeutic action can show both the molecule and its metabolite. The application of quercetin and morin is restricted due to their insolubility in water. Their sulfonic derivatives are well soluble in water and show biological activity as their mother compounds. Therefore, the latter can be more useful for therapy purposes.
PL
Podano przegląd prac, w których metodą potencjometryczną i spektrofotometryczną wyznaczono wartości stałych trwałości kompleksów Al(IIl), Ga(III), In(IIl), Pb(II), Cd(II), Pr(III), Nd(III), Eu(IlI), Er(IlI), Dy(lII) z kwasem kwercetyno-5'-sulfonowym i AI(III), Ga(III), In(III), Co(II), Ni(II), Cu(II), Pb(II), Cd(II) z solą sodową kwasu moryno-5'-sulfonowego.
EN
The potentiometric and the spectrophotometric method was used to determine the stability constants for complexes of AI(III), Ga(III), In(III), Pb(II), Cd(II), Pr(III), Nd(III), Eu(III), Er(III), Dy(lII) with quercetin-5'-sulfonic acid and of Al(III), Ga(III), In(III), Co(II), Ni(II), Cu(II), Pb(II), Cd(II) with sodium salt of morin-5'-sulfonic acid. Investigations were carried out in aqueous solutions at a constant ionic strength I=0,1 (NaClO4).
PL
Zbadano 276 układów do krystalizacji moryny, chryzyny, kwercetyny, ich sulfonowych pochodnych oraz kompleksów z jonami metali. Uzyskano formy krystaliczne dla moryny i soli sodowej kwasu moryno-5'-sulfonowego (NaMSA), sulfonowych pochodnych kwercetyny - kwasu kwercetyno-5'-sulfonowego (QSA-5') i soli sodowej kwasu kwercetyno-8,5'-disulfonowego (Na2QDSA) oraz kompleksów In(III) i Fe(IlI) z chryzyną, które zbadano metodą rentgenografii strukturalnej. Uzyskane wyniki wskazują, że QSA-5' może mieć układ regularny, tetragonalny lub heksagonalny, natomiast pozostałe związki - układ jednoskośny lub trójskośny. Wykonano zdjęcia uzyskanych form krystalicznych metodą elektronowej mikroskopii skaningowej.
EN
The 276 systems to receipt crystalline forms of morin, chrysin, quercetin, their sulphonic derivatives and complexes of metal ions were examined. The crystalline forms of morin, sodium salt of morin-5'-sulphonic acid (NaMSA), quercetin-5'-sulphonic acid (QSA-5'), sodium salt of quercetin-8,5'-disulphonic acid (Na2QDSA) and complexes of In(III) and Fe(III) ions with chrysin were obtained. The method of structural X-rays radiography and electron scanning microscopy were used.
17
Content available remote Quercetin sulfonic derivatives as antidotes to heavy metals
PL
Przeprowadzono badania nad możliwością zastosowania sulfonowych pochodnych kwercetyny jako odtrutek na metale ciężkie (Hg,Cd, Pb). Do badań zastosowano sól sodową kwasu kwercetyno-5'-sulfonowego (NaQSA) i kompleks Mg(II) z QSA. Badania przeprowadzono na szczurach.
EN
Experiments on rats were carried out to learn about the possible application of sulfonic derivatives of quercetin as antidotes to heavy metals (Hg, Cd, Pb). It was found that sodium salt of quercetin-5'-sulfonic acid (NaQSA) shows detoxicative properties with regard to mercury and cadmium ions(II) and complex Mg(II)-QSA with regard to lead ions(II).
19
Content available remote Widma 1H i 13C NMR kwercetyny oraz jej sulfonowych pochodnych
PL
Przeprowadzono badania widm 1H i 13C NMR kwercetyny oraz jej sulfonowych pochodnych - kwasu kwercetyno-5'-sulfonowego (QSA) i soli sodowej kwasu kwercetyno-5'-sulfonowego Na(QSA). Widma te posłużyły do identyfikacji i badania budowy wymienionych związków.
EN
Investigations of 1H and 13C NMR spectra of quercetin and its sulfonic derivatives ­ quercetin-5'-sulfonic acid (QSA) and sodium salt of quercetin-5'-sulfonic acid (NaQSA) were carried out. The spectra were used to identification and structure definition above-mentioned compounds.
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