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Summary

The method of high-performance liquid chromatography (HPLC) with diode array detector (DAD) was used and validated for the simultaneous determination of nine flavonoids (rutin, myricetin, quercitrin, quercetin, luteolin, genistein, kaempferol, apigenin, and isorhamnetin) in beagle dog plasma. Plasma sample was pre-treated with acetonitrile (containing 0.05% formic acid). Chromatographic separation was performed on a kromasil C18 column (250 × 4.6 mm, 5 µm) maintained at 35 °C. The mobile phase was a mixture of methanol and 0.2% formic acid with a step linear gradient. At 1.0 mL min−1 flow rate, the eluent of other eight flavonoids was detected simultaneously at 360 nm with good separation except genistein (detected at 254 nm). Under optimum conditions, the correlation coefficient between the peak area and the concentrations for each analyte was all above 0.999. The intra-day and inter-day precisions were less than 10% for all analytes. The limit of detection and the limit of quantification for the selected nine flavonoids were 0.006–0.03 and 0.02–0.12 g mL−1, respectively. The extracted recoveries of selected nine flavonoids were 74.02%–99.37%. The assay has been successfully applied to determine concentrations of nine flavonoids in plasma from beagle dog after being intravenously administrated Ginkgo biloba extract.

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The aim of this research was to assess the total antioxidant activity (TAA) of lipophilic (Lextr) and hydrophilic (Hextr) tomato extracts using in vitro chemical tests and cell-based assays, focusing on possible synergistic actions between tomato antioxidants. Both Hextr and Lextr were HPLC analysed for their carotenoids, phenolic compounds, and ascorbic acid contents. For the evaluation of TAA, extracts were assayed alone or in combination using in vitro chemical tests (TEAC, FRAP) and cell-based (CAA) assays using human hepatoma (HepG2) and human histiocytic lymphoma (U937) cells. The only carotenoid detected in Lextr was lycopene, while a mixture of phenolic compounds (chlorogenic acid, caffeic acid, and rutin) was identified in Hextr. Ascorbic acid was not found either in Hextr or in Lextr. Upon extract combination (1:1, v/v), the FRAP assay revealed additive action between Lextr and Hextr, whilst a slight synergistic action was observed in TAA as measured by the TEAC assay. Synergistic action was better revealed when TAA was analysed using either U937 or HepG2 cells. This could be explained by the presence of a multiphase media (cell membrane and extra- and intracellular media) that might facilitate the distribution and interaction of antioxidants with different polarities and different mechanisms of action.

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A simple and rapid high-performance thin-layer chromatographic (HPTLC) method has been established for the analysis of rutin, rosmarinic acid, and glycyrrhizin, three active compounds from the decoction of Abnormal Savda Munziq (ASMq) prescription. The method employed silica gel GF254 thin-layer plates as the stationary phase, with ethyl acetate-formic acid-acetic acid-water (15:1:1:1.5, ½/½) as the mobile phase. Following development, plates were observed under ultraviolet (UV) light at 250 nm. The method was validated for linearity, precision, robustness, recovery, limit of detection (LOD), and limit of quantification (LOQ). Linear regression analysis data for the calibration plots showed good linear relationships (r) from 0.9992 to 0.9993. Recovery of the three compounds was between 97.86 and 100.77%. LOD and LOQ were in the range of 33.30–38.17 ng and 110.80–127.26 ng for the three compounds, respectively. The method is rapid, simple, effective, and easy-to-use for ASMq to perform routine quality control analysis and stability studies in commercial preparations.

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E tanulmány két évtizedes kutatómunka eredménye. Arra vállalkozik, hogy - elsősorban külföldi - pszichoszociális fogászati kutatási eredmények alapján felvázolja a fogászati szociológia körvonalait. A budapesti Orvostudományi Egyetem (ma: Semmelweis Egyetem) Magatartástudományi Intézetének megalakulásával (1993) kedvező feltételek alakultak ki a fogászati szociológia kidolgozására. A kilencvenes évek második felében zajlott a külföldi fogászati epidemiológiai-szociológiai-pszichológiai kutatási eredmények szisztematikus feltárására és szintetizálására irányuló irodalomkutatás. Az eredmények alapján felvázolhatók a fogászati szociológia főbb területei: 1. A fogászati páciens. A fogászati státus egyenlőtlenségei, ennek magyarázata a páciens szocioökonómiai státusa alapján. Az orális egészségmagatartás (a napi rutin szájhigiéné stb.) szociális szabályszerűségei. Attitűdök az orális egészségmagatartásban (hiedelem-modell és életminőség). 2. A fogorvos. A fogorvossá válás (szakmai szocializáció) pszichoszociális szabályszerűségei (motivációk stb.) A fogorvosi pályaattitűdök főbb területei, összetevői. A kiégési szindróma (burnout) jelentkezése fogorvosoknál. A fogorvosok társadalmi státusa, különös tekintettel a magyar viszonyokra (privatizáció). 3. A fogorvos-páciens interakciói. A kölcsönös részvétel pszichoszociális modellje. A fogászati szorongás szociológiája (a dentális félelem). A fogorvos-páciens kommunikáció főbb szabályszerűségei. A fogászati páciens elégedettsége, ennek pszichoszociális mutatói. A „jó fogorvosi ellátás”kritériumai.

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In this study thin-layer chromatography (TLC) was used for analysis of the constituents of extracts of tea ( Camellia sinensis L.) and Rooibos ( Aspalathus linearis ) leaves. In particular, flavonoids, a group of phenolic compounds, for example myrecetin, rutin, catechin, quercetin, and kaempferol were analyzed. Extracts of various types of tea, for example black, green, and Rooibos herbal tea (called red tea) were analyzed. The efficiency of extraction of flavonoids from plant material by classical liquid extraction (LE) and supercritical-fluid extraction (SFE) was also compared. Recoveries of individual flavonoids were approximately ten times higher after use of solvent extraction. Separation of flavonoids from tea extracts on the basis of their polarities was optimized by selection of solvents, stationary phases, and chromatographic conditions. For final analyses glass-backed silica gel 60 F 254 plates and the mobile phase acetone-chloroform-water 80:20:10 ( v / v ) were used. UV detection of TLC chromatograms (254 and 366 nm) was used. Better detection of the flavonoids was achieved at 366 nm. The concentration of some important flavonoids in real tea samples was obtained by high-performance liquid chromatography (HPLC).

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JPC - Journal of Planar Chromatography - Modern TLC
Authors: Kunbo Wang, Zhonghua Liu, Jian-an Huang, Donghe Fu, Fang Liu, Yushun Gong, and Xiaosong Wu

The potential of polyamide as adsorbent for separation of nine compounds — (±)-catechin (DL-C), (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECg), (−)-epigallocatechin gallate (EGCg), theaflavin (TF1), theaflavin 3-gallate (TF2A), theaflavin 3′-gallate (TF2B), and theaflavin 3,3′-digallate (TF3) — was studied. Polyamide TLC plates dried with a hair dryer, application as bands, and development in a horizontal chamber gave the best results. Detection was performed using iron(III) chloride-ethanol reagent. Twofold development with chloroform-methanol 2:3 ( v/v ) as mobile phase resulted in the separation of TF1, TF2A, TF2B, and TF3 from all the other compounds. EGCg, ECg, and EGC were separated but EC and DL-C were not separated from each other. The best mobile phase for each of the compounds is reported. The best separation of the five main catechins (EC, DL-C, EGC, ECg, and EGCg) was achieved by use of n -butanol-acetone-acetic acid 5:5:3 ( v/v ). In addition, separation of the flavonols myricetin, quercetin, kaempferol, and rutin and the phenolic acids gallic acid, chlorogenic acid, and caffeic acid was achieved by twofold development with chloroform-methanol 2:3 ( v/v ). The applicability of the method was checked by screening of extracts of green, black, oolong, and pu-erh tea.

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Summary

Artemisia pallens L. (Compositae) is used in Indian traditional medicine to treat diabetes mellitus, jaundice, hysteria, body pain, and bacterial and fungal infections. A major cause of a variety of diseases is oxidative stress which is reduced by antioxidants such as polyphenols. These secondary metabolites are generally ubiquitous in plants and extensively used in the pharmaceutical, cosmetic, and food industries. In this study a simple and sensitive HPLC-UV-MS-MS-based method was developed for separation, identification, and quantification of polyphenols, for example gallic, protocatechuic, chlorogenic, caffeic, and ferulic acids, rutin, quercetin, and kaempferol. Amounts of polyphenols detected in 50% methanol-water extracts of the plant varied from 0.005% (kaempferol) to 0.24% (protocatechuic acid). Separation of the polyphenols was achieved on a reversed-phase C18 with a mobile phase prepared from 1% aqueous with acetic acid and acetonitrile at a flow rate of 0.6 mL min−1. The phenolic compounds were detected by UV absorption at 254 nm. The method was validated for linearity, accuracy, precision, LOD, LOQ, specificity, selectivity, and compound stability. Results from intra and inter-day validation (n = 6) showed the method was efficient and rapid. The optimized method was applied to extracts of A. pallens for identification and quantification of the polyphenols. The reference standards and their presence in A. pallens were confirmed by mass spectrometry.

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Absztrakt

A jobb kamra geometriai és funkcionális változásai számos megbetegedésben nagy jelentőséggel bírnak. Mindazonáltal a rutin echokardiográfiás mérések csak korlátozott diagnosztikus és prognosztikus erővel rendelkeznek. Az olyan modern szívultrahangos technikák, mint a speckle-tracking analízis vagy a 3D echokardiográfia napjainkban már elérhető és könnyen kivitelezhető módszerek, amelyek a jobb kamra komplex felépítésének és működésének költséghatékony, noninvazív vizsgálatát teszik lehetővé. Diagnosztikus értékük és precizitásuk jóval nehezebben hozzáférhető eljárásokat helyettesíthet. Egyre bővülő irodalmi adatok alapján használatuk a mindennapi klinikumban (jobb kamrai infarktus, pulmonalis hypertensio, arrhythmogen jobb kamrai dysplasia, szívtranszplantáció utáni követés, a sportszív differenciáldiagnosztikája) lényeges segítséget jelenthet. Orv. Hetil., 2016, 157(29), 1139–1146.

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Absztrakt

A szerzők fiatal nőbeteg műtéti megoldását ismertetik, akinél súlyos fokú palmaris hyperhidrosis miatt végeztek szimultán bilateralis mellkasi sympathectomiát VATS-módszerrel. Bemutatják az alkalmazott anaesthesiologiai és műtéttechnikai lépéseket. Az 55 perces műtét során végzett Th2-Th3-as ganglionectomia, illetve az érintett sympathicus köteg eltávolítását követően betegük zavartalan kórlefolyás után panaszmentessé vált, hyperhidrosisa megszűnt. Az endoscopos (VATS) thoracalis sympathectomia rutin eljárás súlyos fokú felső testféli (palmaris, axillaris, facialis) hyperhidrosis kezelésére. Kétoldali érintettség esetén racionális elképzelés az egyidejű bilateralis megoldás, melyet a szerzők az alkalmazott VATS-technikával eredményesen végeztek. Röviden vázolják a hyperhidrosis sebészi kezelésének előzményeit. Véleményük szerint a bilateralis megjelenésű kóros izzadékonyság műtéteit, a nemzetközi szakirodalom adataival egybevágóan, célszerűnek látják egy ülésben mindkét oldalon elvégezni. A módszer biztonságos, kellő hatással bír, emellett rövidebb kórházi tartózkodást igénylő eljárás.

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This study was to examine the effects of four fungal polysaccharides, namely exo-polysaccharide (EPS), water-extracted mycelia polysaccharide (WPS), sodium hydroxideextracted mycelia polysaccharide (SPS), and hydrochloric-extracted mycelia polysaccharide (APS) obtained from the endophytic fungus Bionectra pityrodes Fat6, on the sprout growth and flavonoids production of Fagopyrum tataricum. Without obvious changes in the appearance of the sprouts, the exogenous polysaccharide elicitors notably stimulated the sprout growth and functional metabolites accumulation, and the stimulation effect was mainly depended on the polysaccharide species along with its treatment dose. With application of 150 mg/l of EPS, 150 mg/l of WPS and 200 mg/l of SPS, the total rutin and quercetin yield of buckwheat sprouts was effectively increased to 49.18 mg/(100 sprouts), 50.54 mg/(100 sprouts), and 52.27 mg/(100 sprouts), respectively. That was about 1.57- to 1.66-fold in comparison with the control culture of 31.40 mg/(100 sprouts). Moreover, the present study revealed the accumulation of bioactive flavonoids resulted from the stimulation of the phenylpropanoid pathway by fungal polysaccharide treatments. It could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts applied with specific fungal elicitors.

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