Search results for "Tocopherols"
showing 10 items of 25 documents
Bioaccessibility of tocopherols, carotenoids, and ascorbic acid from milk- and soy-based fruit beverages: Influence of food matrix and processing
2012
A study was made of the effect of high-pressure processing (HPP) and thermal treatment (TT) on plant bioactive compounds (tocopherols, carotenoids, and ascorbic acid) in 12 fruit juice-milk beverages and of how the food matrix [whole milk (JW), skimmed milk (JS), and soy milk (JSy)] modulates their bioaccessibility (%). HPP (400 MPa/40 °C/5 min) produced a significant decrease in carotenoid and ascorbic acid bioaccessibility in all three beverages and maintained the bioaccessibility of tocopherols in JW and JS while decreasing it in JSy. TT (90 °C/30 s) produced a significant decrease in tocopherol and carotenoid bioaccessibility in all three beverages and increased the bioaccessibility of …
Preparation and evaluation of lauryl methacrylate monoliths with embedded silver nanoparticles for capillary electrochromatography
2012
In this article, capillary columns constituted by lauryl methacrylate monoliths with embedded silver nanoparticles (AgNPs) were developed and tested. Two incorporation approaches of AgNPs in monoliths were explored. The AgNPs were either photogenerated in situ during polymerization of the monolith by UV irradiation, or incorporated to the polymerization mixture (ex situ). The influence of the AgNP concentration on the morphological and chromatographic properties of the polymer matrix was investigated, and both the in situ and ex situ approaches were comparatively discussed. The morphology of the monoliths was characterized by electron microscopic techniques, and their electrochromatographic…
CD38 expression enhances sensitivity of lymphoma T and B cell lines to biochemical and receptor-mediated apoptosis
2006
CD38 has been widely characterised both as an ectoenzyme and as a receptor. In the present paper, we investigated the role of CD38 as possible modulator of apoptosis. CD38-positive (CD38(+)) and negative (CD38(-)) fractions, obtained by sorting CD38(+) cells from lymphoma T (Jurkat) and lymphoma B (Raji) and by transfecting lymphoma LG14 and myeloid leukemia K562 cell lines, were used. Cellular subpopulations were exposed to different triggers (H(2)O(2), UV-B, alpha-TOS and hrTRAIL) and the extent of apoptosis was determined by Annexin V-FITC/PI assay. Our data showed that, in lymphoma cells, propensity to apoptosis was significantly linked to CD38 expression and that, remarkably, such resp…
Valorization of Wild Apple (
2018
The amplified production of fruit as well as burgeoning demand for plant-made food products have resulted in a sharp increase of waste. Currently, millions of tons of by-products are either being discarded or utilized rather ineffectively. However, these by-products may be processed and further incorporated as functional ingredients in making high-value food products with many physiological and biochemical effects. The chemical analysis of pomace oils using gas chromatography-mass spectrometry (GC/MS) and reversed-phase-liquid chromatography coupled with fluorescence detector (RP-HPLC/FLD) systems led to the identification and quantification of 56 individual lipophilic compounds including u…
Determination of tocopherols in vegetable oils by CEC using methacrylate ester-based monolithic columns
2007
The separation and determination of tocopherols (Ts) in vegetable oils by CEC using methacrylate ester-based monolithic columns has been developed. The effects of pore size of the monolithic columns were studied, and the composition of mobile phase was optimized. The optimal pore size of the monolith was obtained with 12 wt% 1,4-butanediol in the polymerization mixture. Excellent resolution between tocopherols was achieved within 10 min analysis time with a 99:1 v/v MeOH-aqueous buffer containing 5 mM tris(hydroxymethyl)aminomethane at pH 8.0. The LODs were lower than 2.3 microg/mL, and interday and column-to-column reproducibilities at 25 microg/mL were better than 5.6%. Using a 93:7 v/v M…
Prevention of 7-ketocholesterol-induced side effects by natural compounds
2018
Cholesterol oxidation products, also named oxysterols, can be formed either by cholesterol auto-oxidation, enzymatically or both. Among these oxysterols, 7-ketocholesterol (7KC) is mainly formed during radical attacks that take place on the carbon 7 of cholesterol. As increased levels of 7KC have been found in the tissues, plasma and/or cerebrospinal fluid of patients with major diseases, especially age-related diseases (cardiovascular diseases, eye diseases, neurodegenerative diseases), some cancers, and chronic inflammatory diseases, it is suspected that 7KC, could contribute to their development. Since 7KC, provided by the diet or endogenously formed, is not or little efficiently metabol…
Development and validation of a fast and sensitive chromatographic assay for all-trans-retinol and tocopherols in human serum/plasma using liquid-liq…
2002
A sensitive HPLC assay for all-trans-retinol, a-tocopherol, and g-tocopherols in human serum and plasma is reported. Sample preparation is performed in one step and involves precipitation of proteins and extraction of lipids with two volumes of an ethanol–chloroform mixture (3:1, v/v) without I.S. addition. After removal of the precipitated protein, 20 ml aliquots of the supernatant (equivalent to 6.7 ml of serum or plasma) were injected into the HPLC system and analyzed using fluorometric detection. RP-HPLC was performed using a C18 S3 ODS2 column with a methanol–water step gradient (97:3 to 100) at 1.0 ml/min. The quantification limit expressed as nanograms of analyte per milliliter of se…
Fatty acids, sterols and antioxidant compounds of minor and neglected cultivar of Sicilian virgin olive oils
2007
Acidic and sterol composition, pigment fraction and antioxidant compounds (tocopherols, total phenols and polar phenols) from eight monovarietal Sicilian olive oil samples, analyzed during the crop seasons from 2003/2004 to 2005/2006, are reported. Cultivars were divided, according to their diffusion, in main, minor and neglected cultivars. Encouraging data were observed for minor and neglected cultivars, for some revaluation in regard to their relevance, because they showed the highest content in tocopherols, in total phenols and polar phenols compared with main cultivars.
HPLC PROFILE AND EVOLUTION DURING STORAGE OF TRIGLYCERIDES AND DIGLYCERIDES IN VIRGIN OLIVE OILS
2007
Acidic and sterol composition, pigment fraction and antioxidant compounds (tocopherols, total phenols and polar phenols) from eight monovarietal Sicilian olive oil samples, analyzed during the crop seasons from 2003/2004 to 2005/2006, are reported. Cultivars were divided, according to their diffusion, in main, minor and neglected cultivars. Encouraging data were observed for minor and neglected cultivars, for some revaluation in regard to their relevance, because they showed the highest content in tocopherols, in total phenols and polar phenols compared with main cultivars.
Effect of growing area on tocopherols, carotenoids and fatty acid composition ofPistacia lentiscusedible oil
2014
International audience; In this investigation, we aim to study, for the first time, the effect of the growing area on tocopherols, carotenoids and fatty acid content of Pistacia lentiscus fixed oil. Fruits were harvested from eight different sites located in the north and the centre of Tunisia. Tocopherols, carotenoids and fatty acid content of the fixed oils were determined. The highest carotenoid content was exhibited by Feija oil (10.57 mg/kg of oil). Oueslatia and Tabarka oils displayed the highest alpha-tocopherol content (96.79 and 92.79 mg/kg of oil, respectively). Three major fatty acids were determined: oleic, palmitic and linoleic acids. Oleic acid was the main fatty acid presenti…