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Identificação dos flavonóides com atividade antioxidante da cana-de-açúcar (Saccharum officinarum L.) / Identification of the flavonoids with antioxidants activity of the sugar cane (SAccharum officinarum L.)Fabiana Cristina Vila 09 November 2006 (has links)
No presente trabalho estudou-se por métodos analíticos (CCD e CLAE/UV) a atividade antioxidante dos flavonóides presentes na cana-de-açúcar (Saccharum officinarum L.), visando sua possível utilização como alimento funcional. As técnicas CLAE/UV e microfracionamento por CLAE permitiram o fracionamento e o isolamento dos flavonóides, os quais foram analisados por CCD utilizando reagentes específicos para detecção de substâncias antioxidantes. Os resultados obtidos permitiram identificar os flavonóides da cana-de-açúcar (folhas e garapa) com atividade antioxidante, através da comparação dos espectros de UV/DAD e tempo de retenção: orientina-O-ramnosídeo nas folhas e schaftosídeo, isoschaftosídeo, diosmina-8-C-glicosídeo, orientina e 4\',5\'-di-O-metil-luteolina-8-C-glicosídeo na garapa. Estes resultados justificam estudos nutricionais e/ou farmacológicos mais aprofundados a fim de classificar (ou não) a cana-de-açúcar como alimento funcional. / In the present study, analytical methods (TLC and HPLC/UV) were used to evaluate the antioxidant activity of the flavonoids of sugar cane (Saccharum officinarum L.) regarding to its possible use as a functional food. HPLC/UV and HPLC microfractionation techniques allowed fractionation and isolation of the flavonoids, which were evaluated by TLC using specific reagents to detect the antioxidant compounds. The results allowed to identify the flavonoids of sugar cane with antioxidant activity, based on comparison of UV-DAD spectra and retention time: orientin-O-rhamnoside in the leaves and schaftoside, isoschaftoside, diosmetin-8-C-glycoside, orientin and 4\'-5\'-dimethyl-luteolin-8-C-glycoside in the juice. Theses results justify more detailed nutricional and pharmacologic studies to classify (or not) sugar cane as a functional food.
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Desenvolvimento e avaliação de micropartículas de quitosana para a veiculação de dimetilaminoetanol (DMAE) na pele / Development and evaluation of chitosan microparticles containing dimethylaminoethanol (DMAE) for skin vehiculation.Vilma Antonia Lourenço 06 October 2006 (has links)
Micropartículas de quitosana contendo DMAE foram preparadas utilizando o método de coacervação simples. A morfologia das partículas foi observada utilizando um Microscópio Eletrônico de Varredura. O tamanho das partículas foi medido por técnica de espalhamento de luz. As partículas obtidas possuem forma esférica e superfície irregular. Apresentaram uma distribuição de tamanho entre 419 e 528 nm. O pequeno índice de polidispersividade sugere que a distribuição do tamanho de partícula é homogêneo. O rendimento do processo e eficiência de encapsulação foram de 90% e 63%, respectivamente. O desenvolvimento de um novo sistema de liberação requer uma metodologia analítica para a identificação e quantificação do fármaco. Neste trabalho um método simples por cromatografia de fase reversa desenvolvido para a análise do DMAE é apresentado. O DMAE foi analisado utilizando- se uma coluna Merck RP 18 column 5 m (125 x 4 mm D.I.). A fase móvel foi tampão fosfato pH 7,4; acetonitrila (99,5:0,5 v/v) a um fluxo de 0,5 mL.min-1. O comprimento de onda de detecção foi de 208nm à temperatura ambiente (25oC). Linearidade foi obtida para uma faixa de 1,5x10-4 a 6,0x10-4 mol.L-1. Para os ensaios intra e inter dia o coeficiente de variação foi menor que 10%. Este novo método desenvolvido para a quantificação do DMAE apresentou sensibilidade e seletividade, demonstrando ser um método vantajoso e confiável para a realização dos estudos propostos. O método de encapsulação mostrou-se adequado para a preparação de micropartículas de quitosana contendo DMAE, porque apresentou alto rendimento e excelente eficiência de encapsulação. / Chitosan microparticles containing DMAE were prepared by using the simple coacervation method. A scanning electron microscopy (SEM) was used to observe microparticles morphology. Particle size was measured by laser light scattering. Particles presented spherical shape, irregular surface and size distribution between 419 and 528 nm. The small polydispersity index suggested that size distribution is homogeneous. Process yield and encapsulation efficiency were 90% and 63%, respectively. The development of a new drug delivery system requires analytical methods for identification and quantification of this drug. In the present study a simple reversed-phase high performance liquid chromatography developed for DMAE assay is presented. The DMAE was analyzed using/by means of a 5 ?m Merck RP 18 column (125 x 4 mm I.D.). The mobile phase was phosphate buffer pH 7,4; acetonitrile (99,5:0,5 v/v) at a flow rate of 0,5 mL.min-1. Detection was carried out at 208nm at room temperature (25oC). Linearity was obtained from 1,5x10-4 to 6,0x10-4 mol.L-1. Intra and inter- assay coefficient of variation was less than 10 %. This new method developed to assay DMAE presented sensibility and selectivity, providing a useful and reliable means to perform the proposed studies. The encapsulation method was proven suitable to the preparation of chitosan microparticles containing DMAE because it presented high yields and excellent encapsulation efficiency.
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Fytoextrakce metforminu a guanylmočoviny / Phytoextraction of metformin and guanylureaKovářová, Kristýna January 2017 (has links)
Pharmaceutically Active Compounds include metformin, the most often prescripted drug for a treatment of the diabetes mellitus type 2. Metformin is used in high daily doses (up to 3000 mg per day) and it is eliminated by kidneys in its original non - metabolized form. Metformin is degraded in the wastewater treatment plants to guanylurea. The wastewater treatment plants aren't able to clean the waste water, so metformin and guanylurea enter the environment, especially surface water. This diploma thesis deals with the ability to remove metformin and its environmental metabolite guanylurea via phytoextraction technologies. First experiment was focused on phytoextraction of metformin using 5 plant species - Zea mays L., Pisum sativum L., Avena sativa L., Alternanthera reineckii Mini L. and Staurogyne repens L. Second experiment studied phytoextraction of guanylurea using Zea mays L. and Pisum sativum L. The third experiment deals with the phytoextraction of metformin and guanylurea together using Zea mays L. The media of all plants were contaminated by metformin or guanylurea at different concentration levels. The samples of media were taken in 24 hours intervals during the plant cultivation and the decrease of its concentration were studied by HPLC with UV detection at 233 nm for metformin and 210 nm...
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Characterization of antioxidant activities from fruits rich in delphinidin or malvidin anthocyaninsHosseini-Beheshti, Elham 05 1900 (has links)
Anthocyanins have been shown to possess specific antioxidant capacities, which
may provide an underlying protective effect against many chronic diseases . Although the
antioxidant capacity of anthocyanins has been well established, less is known about the
extent to which specific anthocyanin composition affects total antioxidant capacity . The
aim of the present study was to compare the antioxidant capacity of two different soft
fruits, blackcurrant and grape, which have distinctly different anthocyanin profiles.
The anthocyanin profiles of grape and blackcurrant were characterized by
HPLC/MS coupled with a diode array detector. Results showed that blackcurrant
contained four predominant anthocyanins, cyanidin 3-glucoside, delphinidin 3-glucoside,
cyanidin 3-rutinoside, and delphinidin 3-rutinoside . In contrast, malvidin 3-glucoside,
delphinidin 3-glucoside, cyanidin 3-glucoside, petunidin 3-glucoside, and peonidin 3-
glucoside were the major anthocyanins found in grape . The concentration of individual
anthocyanins in all berries was quantified with HPLC/UV using cyanidin 3-glucoside as
an external standard . Finally, results showed a greater (p<0.05) antioxidant capacity of
blackcurrant compared to grape. The total antioxidant capacity of crude extracts from
each was measured by Oxygen Radical Absorbance Capacity (ORAC) and ABTS assays.
Anthocyanin antioxidant capacity index (AACI), derived from the product of
antioxidant (ORAC) activity for each of major anthocyanin present in blackcurrant and
grape, was also used to determine whether the antioxidant capacity of crude anthocyanin
fractions represents either the sum total anthocyanin content or, alternatively, a synergy
between different anthocyanins components . Our results indicated that a plausible
potential synergy between anthocyanin components in regards to ORAC antioxidant
capacity existed in blackcurrant and grape semi-purified anthocyanin extracts.
Furthermore, it could be concluded that both total anthocyanin content as well as
the composition of individual anthocyanins in soft fruits is important to assess total
antioxidant capacity of different berry sources . / Land and Food Systems, Faculty of / Graduate
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Produkce karotenoidů kvasinkami rodu Cystofilobasidium / Production of carotenoi by yeasts of the genus CystofilobasidiumVavrysová, Alena January 2009 (has links)
Carotenoids are important industrial pigments present practically in all living organisms. The aim of presented work is the study of regulation of carotenoid production in yeasts of the genus Cystofilobasidium in presence of exogenous stress factors. Growth curve of C. capitatum exhibited typical two-stage course with prolonged stationary phase similar to other carotenogenic yeasts. Maximal production of biomass and beta-carotene occurred in 103rd hour. Applied stress factors (2-5% NACl, 2-5 mM H2O2, 0,01-1 mM Se(IV), 0,1-5 mM Cr(III)) exhibited no significant influence on biomass production, which reached on average 8-9 g/l. Positive effect was observed in presence of 5mM Cr where 10 g/L of biomass was produced. Beta-carotene formation was positively influenced by many applied stress factors, the highest yield (695 g/g) was reached in presence of 0,1 mM Se(IV). No simultaneous regulation of ergosterol and carotenes was observed in Cystofilobasidium cells. Production properties of yeast strain C. capitatum CCY 10-1-1 wee compared with those of other carotenogenic yeasts of the genes Rhodotorula and Sporobolomyces. C. capitatum produced similar biomass yield as Rhodotorula sp. in presence of salt. Production of beta-carotene by C. capitatum was slightly higher than in Rhodotorula glutinis, but lower than in Sporobolomyces strains which exhibited substantially lower biomass production. Karyotype of C. capitatum is relatively different when compared with karyotype of other carotenogenic yeasts. Based on summary of our results in seems that yeasts C. capitatum exhibit similar physiological as well as production properties as some Rhodotorula strains. Thus, yeasts of the genus Cystofilobasidium could be potentially used to industrial production of carotenoid pigments as well as yeast biomass rich in carotenoids and some biogenic elements.
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Sledování obsahu organických kyselin v alkoholických nápojích / Monitoring of organic acid content in alcoholic drinksOstrihoňová, Katarína January 2017 (has links)
The aim of the thesis is determination and optimization of organic acids in beers using the methods of capillary isotachophoresis (CITP) and high performance liquid chromatography with diode array detection (HPLC/UV). Beer is a complicated matrix therefore the samples need pretreatment using solid phase extraction (SPE). The diploma thesis discusses the optimization of the analytical methods (HPLC/UV and CITP) and optimization of SPE. In the theoretical part, history, characterization and technology of beer production are presented. Further, characteristics of organic acids and methods for organic acid determination are also discussed. The experimental part deals with the preparation of solutions, tested samples, calibration samples. Parameters and procedures of analytical methods (HPLC/UV and CITP) and pretreatment using the solid phase extraction are also described in the experimental part. All results are summarized and compared with the current literature in discussion and conclusion. Eleven beer samples from the retail stores were analyzed. In all samples, six organic acids (lactic, oxalic, succinic, acetic, citric, benzoic) were determined by CITP and five organic acids (lactic, oxalic, succinic, acetic, citric) by HPLC/UV were determined. Results of this study give an overview of the organic acid contents in beer samples.
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HPLC stanovení diastereoisomerů silybinu v plazmě laboratorních zvířat / HPLC determination of silybin diastereoisomers in plasma of laboratory animalsKolářová, Petra January 2012 (has links)
Silybin is the main component of silymarin, a standardized extract obtained from the seeds of milk thistle (Silybum marianum). Flavonolignan silybin has antioxidant, hepatoprotective, chemoprotective and antitumor activities. Natural silybin occurs as an approximately equimolar mixture of two diastereoisomers - silybin A and silybin B. Analytical separation of these diastereoisomers is possible but preparative separation is complicated. The biological activity of the silybin A is different from the silybin B. Silybin diastereoisomers are mainly conjugated to glucuronides and sulfates in organism. A mixture of both silybin diasteroisomers is used in the majority of reported biological, chemical and pharmacokinetic studies. For the first time, optically pure silybin A and silybin B were used for pharmacokinetic study in this thesis. The object of this work was determination of the concentration of free and total silybin in rats plasma in relation to time. Theoretical introduction describes the current state of the problem of chemistry, pharmacology and pharmacokinetics of silybin diastereoisomers. Second part is focused on the selection of appropriate analytical column, chromatographic method and suitable procedure for preparation of biological samples for the determination of the silybin...
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Stanovení niacinu a jeho metabolitů metodou HPLC-MS / Determination of niacin and its metabolites by HPLC-MSPultarová, Kamila January 2014 (has links)
Nicotinic acid (NA) is a hypolipidemic agent with pleiotropic effects on plasma lipoproteins. Its medicamentous form with delayed secretion leads to pyrimidine metabolites, which make increased risk of hepatotoxicity and should be monitored. The aim of the presented study was to introduce HPLC-MS method for the determination of NA, nicotinamide (NAM), nicotinuric acid (NUA), 1-methyl-nicotiamide (MNA), nicotinamid-N-oxide (NNO), 1-methyl-2-pyridon-5-carboxamide (2-Pyr) and 1-methyl- 4-pyridon-5-carboxamide (4-Pyr) in blood plasma useful for the monitoring of hypolipidemic therapy. We have compared calibration dependences of individual metabolites using two columns - Hypercarb (grapfite carbon) and Hypersil Silica (silicagel). Both columns revealed linear calibration dependences for all mentioned analytes except MNA in the concentration range 10-2000 ng/ml for chemical standards; calibration dependence in human blood plasma measured with the column Hypersil Silica was linear in the range 20-4000 ng/ml for all tested analytes. Correlation coefficient varied between the value 0,9400 and 0,9997. Analysis time was 15 min with the column Hypercarb and 27 min with Hypersil Silica. Biological samples were extracted using solid phase with sulphonyl group. Reproducibility of the results of biological samples...
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Popis elektroforetických separačních systémů, využití systémových píků k charakterizaci vlastností surfaktantů a optimalizace složitějších systémů pomocí modelu LFER / Characterization of electrophoretic separation systems,utilization of system peaks for determination of surfactant properties and optimalization of complex separation systems by the LFER modelLokajová, Jana January 2008 (has links)
Conclusions o We have developď new method for CMC determination that is based on the measurementsof sysrem peaks eigenmobilities in capiiluy "t*o"oo"r*tr. The proposed method is moreprecise and eliminates specific systematic errors .o.*'n* when using some s*ndaťdmethods. The proposed method has U".n opti*i""a "o^ia,sysrcm peaks. ..Ý9 .r4. uE'tl UP.lmzeo considering intensities (amplitudes) of o The implementation of mice description ", ",".o".#'ÍÍ.',11Tffi :: jlTl.Ti#'ff ffiTr,"JT::,l:systems. Simulation prognrms curÍently allow user. to cď"ulate system eigenmobilities andeven to optimize the micellar separation systen. We h;\ *:ffi J:ffi.;: oÍ extended simulation o.o,*,",.u".il.;:T"T1'ffi ' ffill: We have clarified the mobi strength, which "uu,", .pri..ll,l?.jln.fi.r::ř""".J:"# peak due to the BGES ionic additional peak has "oo.a,.o in the electrophe.oror, ,oo**"r' As a consequence an :::::::::'*":u.'*..in.*oo.". identifi cation ", i"*,,.,"'ť"i:TT. *i:ajff:oeen possible using rhe set of different derecrion waveilil:" capirrary zone electrophoresis has been used to revear a structure and charge of nanoparticresin the recentry synthesized bulky porymer micelres ,n-'ltt".*, pH regions and to t3 characterize the effect of the PvP fraction added to PS.PMA on the final structure. ouÍ results have confirmed that...
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HPLC analýza léčiv / HPLC Analysis of DrugsKouřil, Tomáš January 2018 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biophysics and Physical Chemistry Candidate: Tomas Kouril Consultant: Ing. Vladimir Kubicek, CSc. Title of Thesis: HPLC analysis of Drugs The diploma thesis describes selection of the most suitable conditions for determination of a two enantiomers of drugs betaxolol and bisoprolol with a method HPLC. The aim of the thesis was to find a suitable isocratic method for the substances for extraction from plasma. The chromatographic column Daicel Chiralcel ® OD-R 4,6 mm x 250 m was utilized. The best results were achieved with mobile phase consisting of acetonitrile and aqueous solution of sodium perchlorate (1 molar) in volume ratio 50:50 for betaxolol and 35:65 for bisoprolol. The column was thermostated at 25 řC. UV detection (λ = 190 nm) was applied to get a sufficient sensitivity. Tramadol and O-desmethyltramadol was tested as an internal standard. Biological samples were tested by LLE before the HPLC analyses. Furthermore, the LLE method for biological samples was tested before performing HPLC.
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