Search results for "phytosterol"
showing 10 items of 87 documents
Anti-proliferative effect of main dietary phytosterols and β-cryptoxanthin alone or combined in human colon cancer Caco-2 cells through cytosolic Ca+…
2015
β-cryptoxanthin (β-Cx) and phytosterols (Ps) have potential against different cancer types, including colon cancer. However, their combined action has not been reported so far. Human colon cancer Caco-2 cells were treated 24 h with β-Cx and/or main dietary Ps (β-sitosterol, campesterol and stigmasterol), alone or in combination, at concentrations compatible with physiological human serum levels. A decrease in cell viability due to apoptosis (rise in sub-G1 population and exposure of membrane phosphatidylserine) was accompanied with dephosphorylation of BAD, mitochondrial depolarization and caspase 3-dependent PARP cleavage, with intracellular Ca2+ influx and increase of RONS levels as initi…
Absence of oxysterol-like side effects in human monocytic cells treated with phytosterols and oxyphytosterols
2012
Oxysterols, found in some commonly consumed foods, can induce a wide range of cytotoxic effects, which have been extensively studied. On the other hand, the side effects of phytosterols and oxyphytosterols are less well-known. Over the past few years, different types of foods have been enriched with phytosterols on the basis of the properties of these compounds that reduce circulating cholesterol levels in certain experimental conditions. It is therefore important to gain better knowledge of the risks and benefits of this type of diet. In this study, conducted in human monocytic U937 cells, the ability of phytosterols (sitosterol, campesterol) and oxyphytosterols (7 beta-hydroxysitosterol, …
Steroidal saponins from Chlorophytum deistelianum.
2016
Abstract Phytochemical investigation of the aerial parts of Chlorophytum deistelianum led to the isolation of four previously undescribed steroidal saponins called chlorodeistelianosides A–D with five known ones. Their structures were established mainly by extensive 1D and 2D NMR spectroscopic techniques and mass spectrometry as (25R)-3β-[(β- d -glucopyranosyl-(1 → 3)-[α- l -rhamnopyranosyl-(1 → 4)]-β- d -xylopyranosyl-(1 → 3)-[β- d -glucopyranosyl-(1 → 2)]-β- d -glucopyranosyl-(1 → 4)-β- d -galactopyranosyl)oxy]-5α-spirostan-12-one, (24S,25S)-24-[(β- d -glucopyranosyl)oxy]-3β-[(β- d -glucopyranosyl-(1 → 2)-[β- d -xylopyranosyl-(1 → 3)]-β- d -glucopyranosyl-(1 → 4)-β- d -galactopyranosyl)ox…
Contribution à l’étude de la fraction insaponifiable de trois huiles d’olive issues des variétés Guasto, Rougette et Blanquette plantés dans l’est al…
2010
The sterol profile of three Algerian virgin olive oils produced from Guasto, Blanquette and Rougette cultivar’s, varieties grown in the East of the country, was established by gas chromatography using a flame ionization detector and coupled to mass spectrometry. Four sterol compounds were identified and characterized in the three oils which are, sitosterol always predominant (43-66%), delta 5-avenasterol (8-13%), stigmasterol (≤ 1,5%) and campesterol (1-2%); one methyl sterol (4-methylsterol) : citrostadienol (4-7%) and two triterpenic alcohols : 24-methylene cycloartanol (10-33%) and cycloartenol (3-13%). These results vary according to campany and variety. Our study shows that most of the…
Sterol Composition in Infant Formulas and Estimated Intake.
2015
Sterol contents in infant formulas (IFs) from the European market were determined, and their intakes by infants between 0 and 6 months were evaluated. Total animal sterols (mg/100 mL) ranged from 1.71 to 5.46, cholesterol being the main animal sterol (1.46-5.1). In general, cholesterol and desmosterol were lower than the human milk (HM) values indicated by other authors. Total plant sterol (mg/100 mL) ranged from 3.1 to 5.0. β-Sitosterol, the most abundant phytosterol, ranged from 1.82 to 3.01, followed by campesterol (0.72-1.15), stigmasterol (0.27-0.53), and brassicasterol (0.14-0.28). Cholesterol intake (mg/day) ranged from 9 to 51 and plant sterol intake (mg/day) from 19 to 50. The ster…
Rapid determination of sterols in vegetable oils by CEC using methacrylate ester-based monolithic columns
2008
A method for the determination of sterols in vegetable oils by CEC with UV-Vis detection, using methacrylate ester-based monolithic columns, has been developed. To prepare the columns, polymerization mixtures containing monomers of different hydrophobicities were tried. The influence of composition of polymerization mixture was optimized in terms of porogenic solvent, monomers/porogens and monomer/crosslinker ratios. The composition of the mobile phase was also studied. The optimum monolith was obtained with lauryl methacrylate monomer at 60:40% (wt:wt) lauryl methacrylate/ethylene dimethacrylate ratio and 60 wt% porogens with 20 wt% of 1,4-butanediol (12 wt% 1,4-butanediol in the polymeriz…
Influence of phytosterols on the structural and dynamic properties of plant plasma membrane
2008
National audience; The complex mixture of sterols, namely phytosterols, found in the plasma membrane (PM) of plant cells is an intriguing characteristic. In the present work, we characterized the sterol composition of tobacco BY-2 cell PM, and we adapted a sterol manipulation method to this plant material. Methyl-b-cyclodextrin was found to induce a drastic reduction of the PM total free sterol content, with a low specificity for the different phytosterols, and without effect on steryl-conjugates. The consequences of phytosterols depletion were investigated by means of fluorescence spectroscopy and biochemical detergent resistant membrane (DRM) fraction purification methods. Data obtained w…
Oxysterols – how much do we know about food occurrence, dietary intake and absorption?
2021
Oxysterols are formed in foods during processing and storage, having an impact on the nutritional profile besides being associated to the development of diverse chronic and degenerative diseases. This review provides an overview on recent information and knowledge gaps on oxysterol formation and absorption from foods. Their contents should be monitored based on dietary habits, in order to have more realistic data available and to expand the currently limited daily intake data. Unraveling the mechanism of oxysterol absorption, together with a more thorough understanding of their metabolism, is needed; in this respect, bioavailability studies using in vitro and in vivo methodologies could con…
Sterol oxidation in ready-to-eat infant foods during storage.
2008
The effect of storage on sterol oxidation of ready-to-eat infant foods was evaluated. Two different flavor (honey -LH- or fruits-LF-) liquid infant foods, prepared with milk and cereals, were stored for 0, 2, 4, 7 and 9 months, at 25ºC. Sterol oxidation products (SOP) were extracted by cold saponification, purified by silica solid-phase and analyzed by gas chromatography (GC) and GC-mass spectrometry. -sitosterol was the most representative sterol, followed by cholesterol and campesterol. No significant differences in the total and single SOP content (0.8-1 mg/kg of product) were observed with respect to storage time and type of sample; the main SOP found was 7-ketositosterol (< …
Tocopherol, fatty acid and phytosterol content in seeds of nine wild taxa of Sicilian Brassica (Cruciferae)
2010
The purpose of this study was to determine tocopherol (Toc), fatty acid and phytosterol content in dry seeds of nine wild taxa of Sicilian Brassica sect. Brassica. Analyses were performed by gas chromatography (GC)-mass spectroscopy (MS). The biochemical analysis of dry seeds showed that in the nine taxa examined, α - and γ -Toc were the major isomers, δ - Toc was present in traces and β -Toc was never found. All taxa had a similar fatty acid composition with C 16:0 (357.2 mg kg − 1 DW), C 18:1 (393.94 mg kg − 1 DW) and C 22:1 (618.29 mg kg − 1 DW) acids present in higher amount. Unsaturated fatty acids (52.5–66.5%) were more abundant than saturated (33.5–47.5%) ones relative to the total f…