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Micellar Electrokinetic Chromatography Method for Determination of the Ten Water-Soluble Vitamins in Food Supplements Полный текст
2013
da Silva, Danielle C. | Visentainer, Jesuí V. | de Souza, Nilson E. | Oliveira, Cláudio C.
The separation and determination of the ten water-soluble vitamins by using capillary electrophoresis in the micellar electrokinetic chromatography in a single run are proposed. The method uses low toxicity and cost solvent (ethanol) as modifier of background electrolyte (BGE) attending to the Green Chemistry principles. The electrophoretic method uses 10.0 % (v/v) ethanol, 2.0 % (w/v) SDS, 0.02 mol L⁻¹borate at pH 8.70 as BGE. The standard and real sample solutions were injected in the eletrophoretic system by hydrodynamic injection under pressure of 0.80 psi for 8 s, and the separation was carried out in a fused silica capillary under a potential of 28 kV at 25 °C; the analytical signals were monitored at 214 nm. The analytical method is precise (r.s.d. < 6 %), accurate (better than 9 %), selective, sensitive, robust, simple, and presents high analytical frequency as ten water-soluble vitamins were separated in only 18 min, with migration times of 5.75 ± 0.02, 6.81 ± 0.02, 8.13 ± 0.04, 8.80 ± 0.07, 8.98 ± 0.06, 11.10 ± 0.08, 11.34 ± 0.05, 13.85 ± 0.15, 14.82 ± 0.04, and 17.85 ± 0.30 min. Detection and quantification limits of 0.34, 0.32, 0.27, 0.20, 2.50, 4.98, 4.92, 0.30, 0.86 and 0.28 mg L⁻¹and 1.02, 0.97, 0.83, 0.62, 7.56, 15.09, 14.91, 0.90, 2.59 and 0.83 mg L⁻¹, for vitamins PP (nicotinamide), B₁₂(cyanocobalamin), B₂(riboflavin), B₆(pyridoxine), B₈(biotin), C (ascorbic acid), B₅(pantothenic acid), B₃(nicotinic acid), B₁(thiamine), and B₉(folic acid), respectively. Excellent recoveries (intra and inter-day) were obtained and, when the method was applied to food supplement analyses the results were in agreement with the conventional HPLC methods.
Показать больше [+] Меньше [-]Fat mimetic capacity of Chlorella vulgaris biomass in oil-in-water food emulsions stabilized by pea protein
2005
Raymundo, A. | Gouveia, L. | Batista, A.P. | Empis, J. | Sousa, I.
Vegetable proteins proved to be good emulsifiers for food emulsions with dietetic advantages. The use of these emulsions as carriers for healthy ingredients, such as colourings, with antioxidant and other beneficial properties, is an interesting subject. In this work, the capacity of the biomass of the microalga Chlorella vulgaris (which has been widely used as a food supplement) as a fat mimetic, and its emulsifier ability, was evaluated. Pea protein emulsions with C. vulgaris addition (both green and orange - carotenogenic) were prepared at different protein and oil contents. The rheological properties of the respective food emulsions were measured in terms of the viscoelastic properties and steady state flow behaviour and texture properties. It was observed that the two microalgal forms evidenced a fat mimetic capacity in these emulsions, the performance of the green stage of this C. vulgaris organism was significantly (p < 0.05) better than the orange stage.
Показать больше [+] Меньше [-]Food analysis – samples preparation and chromatographic methods in determination of selected biogenic amines, methylxanthines and water-soluble vitamins Полный текст
2012
Płonka, Joanna
The expanding demands of consumers requires food quality control to be improved all the time. Higher concentration of biogenic amines can lead to food toxicity, for example they can cause migraine headaches in people who consume products rich of serotonin or tyramine. Methylxanthines (caffeine and metabolites) can also have side effects to human comfort – high doses can lead to unrest, irritation or insomnia. Most vitamins are supplied to humans only as a part of food meals or dietary supplements. Knowledge about their concentration in food can be useful for composing various diets. In this work specification of complete sample preparation parameters for extraction of the compounds from food matrices has been reviewed. Particular attention was given to the preparation stage as well as to extraction methods that have been used. The second part of the work presents data from chromatographic methods for determination and separation of selected biogenic amines, methylxanthines and water-soluble vitamins in food. Stationary and mobile phases, detection methods as well as validation data have been reviewed. This publication is a comprehensive compendium of analytical procedures for food analyses of the previously mentioned compounds.
Показать больше [+] Меньше [-]Physicochemical and in vitro biological validation of food grade secondary oil in water nanoemulsions with enhanced mucus-adhesion properties Полный текст
2022
Lagreca, Elena | Vecchione, Raffaele | Di Cicco, Chiara | D’Aria, Federica | La Rocca, Alessia | De Gregorio, Vincenza | Izzo, Luana | Crispino, Raffaele | Mollo, Valentina | Bedini, Emiliano | Imparato, Giorgia | Ritieni, Alberto | Giancola, Concetta | Netti, Paolo Antonio
Among oral delivery systems, oil in water nano-emulsions (O/W NEs) are of particular interest to improve pharmacokinetics of lipophilic compounds. Recently, we have implemented a successful strategy to improve O/W NEs stability, based on a polymeric coating on an oil core, namely secondary O/W NEs, through the use of pharma grade formulations. However, in the field of food supplements, food grade materials are the top choice since they combine safety and cost effectiveness. Here, we have replaced pharma grade (PG) with food grade (FG) materials in the preparation of the polymer coated O/W NEs, and performed a comparative study between the two formulations to assess the FG one. At the same time, in order to provide formulations with enhanced mucus-adhesion to the intestinal barrier, secondary O/W NEs were prepared by adding thiol groups to chitosan (Ct) via a simple non-covalent procedure based on N-acetyl-cysteine (NAC) salification, thus easily implementable to a food supplement formulation. PG and FG formulations, in different materials combinations, were prepared and physico-chemically characterized (DLS, ¹H NMR, ITC, CRYO-TEM) showing similar behaviour. FG formulations (NEs, Ct-NEs and Ct-NAC-NEs) loaded with curcumin were prepared and compared with the free drug in terms of drug bioaccessibility through the INFOGEST protocol confirming improved bioaccessibility. Very interestingly, by comparing mucus-adhesion properties of the two polymeric coatings (Ct and Ct-NAC) within an intestine on chip device able to mimic the complex intestinal functions, a significant enhancement in the mucus-adhesive properties of the proposed novel Ct-NAC-NE formulation was observed with respect to Ct due to the presence of thiol groups. Nonetheless, in-vivo assays are required as a final assessment of the proposed system.
Показать больше [+] Меньше [-]Sugar beet pectin as a natural carrier for curcumin, a water-insoluble bioactive for food and beverage enrichment: Formation and characterization Полный текст
2021
Zagury, Yedidya | David, Shlomit | Edelman, Ravit | Hazan Brill, Roni | Livney, Yoav D.
Food and beverages enrichment with water-insoluble health-promoting nutraceuticals is important, but technologically challenging. Sugar beet pectin (SBP) is a natural dietary fiber with high emulsifying capacity. However, its potential as a natural encapsulator of hydrophobic nutraceuticals for beverage enrichment, has hardly been explored. Curcumin is a potent antioxidant with numerous attributed health benefits, but very low aqueous-solubility. We herein explored SBP as a carrier for solubilization and protection of curcumin (CUR). Using spectrofluorimetry, the CUR-SBP binding constant determined was (6.74 ± 0.5) ∙ 10⁵M⁻¹. As CUR:SBP molar ratio increased from 14:1 to 140:1, CUR encapsulation capacity increased from 14.5 ± 0.8 to 127.4 ± 0.4 mg CUR/gSBP, and encapsulation efficiency moderately decreased from ~100% to 86 ± 7%. The encapsulation in SBP dramatically decreased CUR particle size, from >17 μm to <0.5 μm, in average, and conferred substantial protection to CUR during simulated shelf-life, decreasing the decay rate constant ~7 fold. Therefore, SBP is a potent natural encapsulator for hydrophobic nutraceuticals for food and even clear beverage enrichment.
Показать больше [+] Меньше [-]Liquid Chromatographic Determination of the Cyanobacterial Toxin β-N-Methylamino-l-Alanine in Algae Food Supplements, Freshwater Fish, and Bottled Water
2009
Scott, Peter M. | Niedzwiadek, Barbara | Rawn, Dorothea F.K. | Lau, Ben P.Y.
β-N-Methylamino-l-alanine (BMAA) is a neurotoxin originally found in cycad seeds and now known to be produced by many species of freshwater and marine cyanobacteria. We developed a method for its determination in blue-green algae (BGA) food supplements, freshwater fish, and bottled water by using a strong cation-exchange, solid-phase extraction column for cleanup after 0.3 M trichloroacetic acid extraction of BGA supplements and fish. Bottled water was applied directly onto the solid-phase extraction column. For analysis of carbonated water, sonication and pH adjustment to 1.5 were needed. To determine protein-bound BMAA, the protein pellet left after extraction of the BGA supplement and fish was hydrolyzed by boiling with 6 M hydrochloric acid; BMAA was cleaned up on a C18 column and a strong cation-exchange, solid-phase extraction column. Determination of BMAA was by liquid chromatography of the fluorescent derivative formed with 9-fluorenylmethyl chloroformate. The method was validated by recovery experiments using spiking levels of 1.0 to 10 μg/g for BGA supplements, 0.5 to 5.0 μg/g for fish, and 0.002 μg/g for bottled water; mean recoveries were in the range of 67 to 89% for BGA supplements and fish, and 59 to 92% for bottled water. Recoveries of BMAA from spiked extracts of hydrolyzed protein from BGA supplements and fish ranged from 66 to 83%. The cleanup developed provides a useful method for surveying foods and supplements for BMAA and protein-bound BMAA.
Показать больше [+] Меньше [-]Effects of dietary fibers with high water-binding capacity and swelling capacity on gastrointestinal functions, food intake and body weight in male rats Полный текст
2017
Tan, Chengquan | Wei, Hongkui | Zhao, Xichen | Xu, Chuanhui | Peng, Jian
Objective: The aim of this study was to investigate the effects of supplementation of dietary soluble fibers with high water-binding capacity (WBC) and swelling capacity (SC) on gastrointestinal tract mass, physicochemical properties of digesta, gastrointestinal mean retention time (MRT), body weight, and food intake in male rats. Methods: Thirty-two male Sprague-Dawley rats were randomized to four equal groups and fed the control diet or diet containing 2% konjac flour (KF), pregelatinized waxy maize starch plus guar gum (PWMS+GG), andPWMS plus xanthan gum (PWMS+XG) for three weeks. Results: WBC and SC of diets followed the order of PWMS+GG > KF > PWMS + XG > control. PWMS+GG and KF groups had a lower average daily food intake than the control group, but all the groups showed no difference in final body weightand the weight gain rate. The high WBC and SC of the PWMS+GG and KF groupsled to an increase of WBC and SC in the stomach digesta, and a gain of the cecal digesta weight, due to increased cecal moisture content. Conclusion: The inclusion of the novel fiber, PWMS+GG, in the diet of male rats appears to facilitate the modulation of WBC and SC of stomach digesta and the reduction of food intake.
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