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The extraction of crude drugs by using different solvents provides polarity-based fractions containing specific types of secondary metabolites. Averrhoa carambola L. fruits were extracted and fractionated, and petroleum ether extract was processed by fatty acid methyl ester (FAME) technique for characterization by gas chromatography‒mass spectrometry (GC‒MS) analysis. The remaining part was extracted with methanol for high-performance thin-layer chromatography (HPTLC) analysis, for simultaneous quantitative determination of gallic acid, protocatechuic acid, and quercetin in methanolic fractions. Petroleum ether and methanol fractions were found to be the best for the highest possible recovery of target analytes. The chromatographic elutions of FAME compounds generated from ether extract were evaluated by GC‒MS profiling. Ten fatty acid compounds were separated with the highest quantity of oleic acid methyl ester (42.88%). On other hand, polar fraction was processed by HPTLC profiling. For achieving good separation, a mobile phase of toluene‒ethyl acetate‒formic acid (5:4:1, v/v) was used. The densitometric determination was carried out at 310 nm in reflection–absorption mode. The calibration curves were linear in the range of 100–600 ng per spot for gallic acid, protocatechuic acid, and quercetin. During the analysis, the dried raw material from A. carambola L. fruits showed the presence of gallic acid (0.96%), protocatechuic acid (0.05%), and quercetin (0.40%). The proposed method is simple, precise, specific, and accurate. The statistical analysis of the data obtained proves that the method is reproducible and selective and can be used for the routine analysis of the reported phenolic compounds in crude drug and extracts. The results indicated that the methanolic extracts of the plant contained a considerable amount of bioactive compounds. The presence of phytochemicals especially phenolics and flavonoids explains its use in various diseases. It may be concluded that the results obtained from the quantitative evaluation of quercetin by HPTLC fingerprinting could be useful in its authentication, the quality control of the drug, and in ensuring therapeutic efficacy.

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Lübeck, M., Alekhina, I. A., Lübeck, P. S., Jensen, D. F., Bulat, S. A. (1999) Delineation of Trichoderma harzianum Rifai into two different genetic entities by a highly robust fingerprinting method, UP-PCR. Mycol. Res. 103 , 289

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Acta Chromatographica
Authors: Mei-Xia Zhu, Sheng-Nan Li, Hai-Dan You, Bin Han, Zhi-Ping Wang, Yan-Xi Hu, Jin Li, and Yu-Feng Liu

, A feasible strategy for applying chromatography fingerprint to assess quality of Chinese Herbal Medicine, in Proceedings of the International Symposium on Quality of TCM with Chromatographic Fingerprint, Guangzhou, China, 2001

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): Qualifying pharmaceutical substances by fingerprinting with NIR spectroscopy and the polar qualification system. Spectroscopy , 10 , 46-49. Qualifying pharmaceutical substances by fingerprinting with NIR spectroscopy and the polar

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fingerprint. — Nucleic Acids Res. 23:4407–4414. Bleeker M. AFLP: A new technique for DNA fingerprint Nucleic Acids Res. 1995

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Thermal treatment and analysis

The art of adjacent (near-equilibrium) studies

Journal of Thermal Analysis and Calorimetry
Author: J. Šesták

Abstract  

Heating and/or cooling of substances is one of the oldest and basic methods for preparing materials with defined properties. This always leaves a definitive fingerprint of the thermal history. Beside knowing the structure we need to specify such materials by their thermodynamic behaviour, i.e., stability/metastability, phase relations and transitions, particularly establishing corresponding characteristic points. All this can be based on ordinary thermodynamics but its validity must be approved for non-equilibrium conditions of temperature changes where equilibrium and kinetic effects overlap. The slower the phase transition proceeds the greater is the deviation of the system state (kinetic curve) from its equilibrium state (equilibrium background). This makes possible to locate the actual phase boundary between two states investigated, resulting in the so-called kinetic phase diagrams. Most of modern technologies are intentionally based on non-equilibrium phenomena in order to create metastable/nonstable phases of specific properties. In this sense thermal analysis is understand as the method for determining the sample state on the basis of the sample interactions with the surroundings whose intensive parameters are controlled. Temperature is here considered as a basic parameter that connects all thermophysical measurements and thermal treatments.

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Absztrakt:

A bélflóra olyan, mint az ujjlenyomat: minden embernek egyedi összetételű, rá jellemző baktériumfajokból álló mikrobanépesség él a bélrendszerében, amit ma bélmikrobiomnak hívunk. A baktériumok változatosságának, sokszínűségének (diverzitásának) csökkenése szoros kapcsolatot mutat a funkcionális bélbetegségekkel, az elhízással, a 2-es típusú diabetesszel és a cardiovascularis betegségekkel, valamint sok autoimmun megbetegedéssel. A székletgenomikai teszt során a bélflórát alkotó fajok pontos identifikálása és filogenetikai azonosítása révén meghatározható a diverzitás változása, illetve azonosítható bizonyos bélbaktériumok túlnövekedése. Praehypertoniás, hypertoniás egyénekben a Firmicutes törzshöz tartozó baktériumok elszaporodása, míg a Bacteroidetes törzsek csökkenése gyakrabban volt kimutatható, mint normotonia esetén, mindemellett az egyes baktériumtörzsek fiziológiai aránya kevésbé volt kiegyenlített. Az első megfigyelések arra utalnak, hogy kapcsolat állhat fenn a magas vérnyomás és az intestinalis baktériumflóra egyensúlyának megbomlása között, mind állatkísérletekben, mind emberben észlelhető hypertonia esetén. A vizsgálatok eredményei azt is felvetik, hogy a bél mikrobiotájának étrenddel történő célzott befolyásolása a magas vérnyomás nem gyógyszeres kezelésének új innovatív módszere lehet. Orv Hetil. 2018; 159(9): 346–351.

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phenotypes, resistance determinants and DNA fingerprints of Salmonella enterica serotype Typhimurium isolated from bovine in Southern Japan. Int. J. Antimicrob. Agents 30 , 150–156. Okamoto K

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., Mitchell, T. G.: Identification of clinical strains of Candida albicans by DNA fingerprinting with polymerase chain reaction. Mycoses 36 , 171 (1993). Identification of clinical strains of Candida albicans by DNA

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., Catimel, B., Luchansky, J. B., Ojeniyi, B., Rocourt, J.: Genomic fingerprinting of 80 strains from WHO multicenter international typing study of Listeria monocytogenes via pulsed-field gel electrophoresis (PFGE). Int J Food Microbiol 32 , 343 (1996

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