Materias
(48)
Refinar búsqueda
texto impreso
texto impreso
A method was devised to assay four forms of vitamin C: L-ascorbic acid (AA), dehydroascorbic acid (DHA), ascorbate-2-mono- and polyphosphate (AMP, APP), as well as ascorbate-2-monosulphate (AMS), in sample series of different fish tissues and fe[...]
texto impreso
Naturally occurring folates exist in multiple forms, differing in pteridine ring structure and number of glutamate residues. The ability to measure these folate coenzymes in tissues and cells gives important information about in vivo folate meta[...]
documento electrónico
T. RAJASEKARAN, Autor ; A. RAMAKRISHNA, Autor ; K. UDAYA SANKAR, Autor ; P. GIRIDHAR, Autor ; G. A. RAVISHANKAR, Autor | 2008Stevia reabudiana is gaining popularity especially in making diabetic food supplements in view of its non-nutritive glycosides. Steviosides profile in ex vitro and in vitro leaves and callus cultures of S. rebaudiana were investigated by HPLC an[...]
texto impreso
In this study several properties of acetonitrile-water (ACN-water) mixtures were examined which have an influence on the liquid chromatography (LC) behavior of ionizable compounds, such as Debye-Hückel parameters, pH scale, LC-useful pH range an[...]
texto impreso
documento electrónico
Article : documento electrónico
JACQUES PRODOLLIET, Autor ; MILENE BRUELHART, Autor |A liquid chromatographic method was evaluated for the determination of the intense sweetener acesulfam-K in tabletop sweetener, candy, soft drink, fruit juice, fruit nectar, yogurt, cream, custard, chocolate, and biscuit commercial preparations.[...]
texto impreso
ISABELLE SCHMITZ-AFONSO, Autor ; JORGE E. LOYO-ROSALES, Autor ; MARIA DE LA PAZ AVILES, Autor ; BARNETT A. RATTNER, Autor ; CLIFFORD P. RICE, Autor | 2003A quantitative method for the simultaneous determination of octylphenol, nonylphenol and the corresponding ethoxylates (1 to 5) in biota is presented. Extraction methods were developed for egg and fish matrices based on accelerated solvent ext[...]
texto impreso
A high-performance liquid chromatographic method has been developed for determination of ascorbic and dehydroascorbic acid. Samples were extracted with 62.5 mM metaphosphoric acid and ascorbic acid determined using an ion-exclusion column with d[...]
texto impreso
A rapid and simple method using reversed-phase high-performance liquid chromatography combined with indirect visible photometry at 433 nm was developed to determine cyclamate in some food samples. Cyclamate was not detected in these chosen sampl[...]
texto impreso
texto impreso
A simple method for the determination of glucosamine and lactose in milk-based formulae by high-performance liquid chromatography (HPLC) with refractive index detector was developed and validated. Samples were cleaned up just by protein precipit[...]
texto impreso
HPLC methods described so far for the determination of thiamine and riboflavin in meat samples have used mostly fluorescence detection. The aim of this work was to elaborate a suitable method with UV detection for this purpose and to compare the[...]
texto impreso
Liquid chromatographic methodology for determination of vitamin C and organic acids in different fruits (whortleberry, blackberry, red currant, black currant, raspberry, babaco, feijoa, kiwano, passion fruit, red and yellow tamarillos, medlar, a[...]
documento electrónico
ADRIENNE McMAHON, Autor ; S. CHRISTIANSEN, Colaborador ; F.-F. CHEE, Colaborador ; A. CHUA, Colaborador ; H. BRADDOCK, Colaborador ; B. GILL, Colaborador ; RAQUEL DE GUZMAN, Colaborador ; K. KOHLER, Colaborador ; D.P. LABITAN, Colaborador ; J. LE GRANDOIS, Colaborador ; E. MARCEAU, Colaborador ; F. MARTIN, Colaborador ; S. MENG JENSEN, Colaborador ; L. MEYER, Colaborador ; D. PIOT, Colaborador ; L. RAEL, Colaborador ; KAREN SCHIMPF, Colaborador ; M. THOMPSON, Colaborador ; TORRES, MARINA, Colaborador | 2016The main objective of the AOAC Stakeholder Panel on Infant Formula and Adult Nutritionals (SPIFAN) project is to establish international consensus methods for infant formula and adult nutritionals, which will benefit intermarket supply and dispu[...]
documento electrónico
TORRES, MARINA ; BALDIGA, NATALIA ; AMUEDO, VIVIANA ; TORRE, ALEJANDRA | Montevideo [URUGUAY] : Laboratorio Tecnológico del Uruguay (LATU) | 2008La Fortificación de alimentos es muy común en estos días. Nuestro país está alineado con esta tendencia y está desarrollando muchos productos nuevos fortificados. Uno de esos productos son las galletitas fortificadas. Nosotros trabajamos en un m[...]
texto impreso
The influence of coexisting fat on the extraction of tocopherols (Toc) and tocol, as an internal standard, with n-hexane after saponification was studied.
documento electrónico
LUKAS TAUJENIS, Autor ; VILMA OLSAUSKAITE, Autor ; AUDRIUS PADARAUSKAS, Autor | 2014
texto impreso
NDAW, S., Autor ; AOUDÉ-WERNER, D. , Autor ; BERGAENTZLE, M., Autor ; HASSELMANN, C., AutorTreatment with a mixture of enzymes (a-amylase, papain and acid phosphatase) led to the release in a single step of the different forms (phosphorylated and protein-bound) of the vitamins B1, B2 and B6 present in various food samples, not supplem[...]
Article : documento electrónico
SAMY H. ASHOOR, Autor ; GEORGE J. SEPERICH, Autor ; WOODROW C. MONTE, Autor ; JIM WELTY, Autor |A method was developed for determining caffeine in decaffeinated coffee, tea, and beverage products by high performance liquid chromatography (HPLC). The HPLC system consisted of a Bio-Sil ODS-5S C18 column, methanol-water (25 + 75) mobile phase[...]
texto impreso
A high performance liquid chromatography (HPLC) method has many advantages when compared with conventional methods for analysis of lactose in milk.
documento electrónico
M.MÍGUEZ BERNÁRDEZA, Autor ; J DE LA MONTAÑA MIGUÉLEZ, Autor ; J. GARCIA QUEIJEIRO, AutorThe major components in chestnut (Castanea sativa Mill) are carbohydrates, mainly starch, followed by sucrose. This disaccharide is one of the most important parameters for the assessment of the commercial quality of these fruits. In this study [...]
texto impreso
Taurine (2-aminoethanesulfonic acid) is a conditionally essential amino acid. While it can be synthesized by healthy adults from methionine and cysteine and it can be absorbed from foods (generally skeletal muscle) that contain it, preterm infan[...]
texto impreso
The amino acid taurine (2-aminoethanesulfonic acid) is present in many sports drinks claiming to provide you with some special advantage. While taurine is not incorporated into proteins, our bodies contain a good amount (approximately 70 g in a [...]
texto impreso
Separation of polar compounds on polar stationary phases with partly aqueous eluents is by no means a new separation mode in LC. The first HPLC applications were published more than 30 years ago, and were for a long time mostly confined to carbo[...]
documento electrónico
TAO PANG, Autor ; Z. YUAN, Autor ; Y. DAI, Autor ; CH. WANG, Autor ; J. YANG, Autor ; L. PENG, Autor ; GUOWANG XU, Autor | 2007HPLC-atmospheric pressure chemical ionization MS (HPLC-APCI-MS) was used to screen and identify glycosides in tobacco leaf. MS/MS and MS3 and photodiode array (PDA) detection were also used in the characterization. A total of 12 glycosides were [...]
texto impreso
documento electrónico
ÚRSULA WOLWER-RIECK, Autor ; WERNER TOMBERG, Autor ; ANDREAS WAWRZUN, AutorThe stability of the two steviol glycosides stevioside and rebaudioside A and the possible formation of the aglycon steviol in different soft drinks were analyzed in samples spiked with stevioside or rebaudioside A after 24, 48, and 72 h storage[...]
documento electrónico
KAREN W. PHINNEY, Autor ; RIMMER, CATHERINE, Autor ; JEANICE BROWN THOMAS, Autor ; SANDER, LANE C., Autor ; SHARPLESS, KATHERINE E., Autor ; WISE, STEPHEN A., AutorVitamins are essential to human health, and dietary supplements containing vitamins are widely used by individuals hoping to ensure they have adequate intake of these important nutrients. Measurement of vitamins in nutritional formulations is ne[...]
texto impreso
A reversed-phase high-performance liquid chromatographic method is described for a stability-indicating assay of folic acid in multivitamin preparations. This method shows excellent recovery and precision characteristics, allows the determinatio[...]
documento electrónico
In this book, I have tried to show the way in which high performance liquid chromatography–mass spectrometry (LC–MS) has developed, somewhat slowly it has to be said, into a powerful hybrid analytical technique.In the first chapter, I have discu[...]
Article : texto impreso
Un método rápido y fácil que utiliza la cromatografía líquida de alta presió ( HPLC) se ha propuesto para determinar almidón en papel: El almidón es convertido en dextrosa por hidrólisis del almidón con enzimas.Agregando una cantidad conocida de[...]Article : texto impreso
Determinación de Flufenoxuron en el aire y en el polvillo en interiores. Un preservante de madera curativo que contiene 0.02% de Flufenoxuron ( Flurox ) fué aplicado sobre una extensa área en una sala de ensayos. Varias aplicaciones originaron [...]Article : texto impreso
PLATEN, A., Autor ; HÖLBACHER, G., Autor ; WEGEN, H.-W., Autor |Determinación de Flufenoxuron en el aire y en el polvillo en interiores. Un preservante de madera curativo que contiene 0.02% de Flufenoxuron ( Flurox ) fué aplicado sobre una extensa área en una sala de ensayos. Varias aplicaciones originaron [...]
texto impreso
A rapid and simple method for the determination of taurine (2-aninoethanesulphonic acid) in complex samples is described. It is based on the HPLC separation of the dinitrophenyl (DNP) derivative of taurine. The reaction conditions are selected t[...]
texto impreso
Taurine (2-aminoethanesulfonic acid) was quantitated by reversed-phase chromatography on a C18. Resolve column using a linear gradient of 9-l 1% methanol in water. Glutamine was used as the internal standard. Pre-column derivatization of the am[...]
texto impreso
In the present paper the results of the determination of lactose in milk by polarimetry (POL), high-performance liquid chromatography (HPLC), enzymatic assay (ENZ) and reductometry (RED) have been compared.
documento electrónico
JAMES OLIVER, Autor ; MARIANNE GABORIEAU, Autor ; EMILY HILDER, Autor ; PATRICE CASTIGNOLLES, Autor | 2013Carbohydrates partially liberated by acid hydrolysis of plant fiber can be separated by hydrophilic interaction liquid chromatography (HILIC), ligand-exchange liquid chromatography or other forms of LC with ion-exchange columns. However, the rob[...]
texto impreso
A simple automated extraction method for the determination of alkylphenolic compounds in fish tissue is reported. Pressurized fluid extraction is used to extract ground fish tissue, and the resulting extract is purified on aminopropyl silica ([...]
texto impreso
An automated reversed phase high performance liquidchromatography (W-HPLC) method is described, for the simultaneous analysis of water soluble [ascorbic acid (C). nicotinic acid, nicotinamide. folic acid, cyanocobalaniine (BIZ). and riboflavin ([...]
texto impreso
A unified extraction and quantification procedure based on stable isotope-dilution liquid chromatography/tandem mass spectrometry (LC/MS/MS) has been developed for the simultaneous determination of total homocysteine and folate (5-methyltetrahyd[...]
texto impreso
DESMARCHELIER AURÉLIEN, Autor ; GUILLAMON CUADRA MIRIAM, Autor ; THIERRY DELATOUR, Autor ; PASCAL MOTTIER, AutorAn isotope dilution liquid chromatography-electrospray ionization tandem mass spectrometry method for the simultaneous determination of melamine and cyanuric acid in cow’s milk(range of 0-0.3 mg/kg)and milk-based infant formulas(ranges of 0-0.[...]
documento electrónico
SUN, JING, Autor ; YANG, Autor ; HSIAOWAN LEE, Autor ; LIN WANG, Autor | 2015The simultaneous separation and determination of As(III), As(V), monomethylarsenic acid (MMA), dimethylarsenic acid (DMA), Cr(III), Cr(VI) and Cd(II) in water samples have been carried out by anion exchange liquid chromatography with inductively[...]
documento electrónico
CATTANEO, T. M. P., Autor ; MARINONI, L., Autor ; BARZAGHI, S., Autor ; CREMONESI, K., Autor ; MONTI, L., Autor | 2011Aflatoxin M1 (AFM1) is a toxic undesirable compound in milk. AFM1 affinity for caseins causes a concentration effect during milk process for dairy transformation. In spite of this, no official method of analysis, nor maximum tolerance level for [...]
texto impreso
Tissue distributions and seasonal dynamics of the hepatotoxic microcystins-LR and -RR in a freshwater snail (Bellamya aeruginosa) were studied monthly in a large shallow, eutrophic lake of the subtropical China during June–November, 2003. Micr[...]
texto impreso
A simple post-column ion-pair extraction system was constructed from commercially available tees and tubing (made of chemically inert polymeric materials) and evaluated for the liquid chromatographic (LC) determination of cyclamate and related s[...]
