Effect of simulated gastrointestinal digestion on plant sterols and their oxides in enriched beverages
Abstract This study evaluates the bioaccessibility (percentage of soluble compound available for absorption) of plant sterols (PS) and their oxides (phytosterol oxidation products, POPs) after simulated gastrointestinal digestion in fruit (Fb), milk (M) and fruit-based milk beverages with (FbM a ) or without (FbM b ) tangerine juice. In beverages and their bioaccessible fraction (BF), campesterol, campestanol, stigmasterol, β-sitosterol and sitostanol were detected. Bioaccessibility of total PS ranged between 2.62 and 6.48%, FbM b yielding the highest value, followed by FbM a > Fb > M. Campesterol/campestanol were the most bioaccessible PS. Only oxides of β-sitosterol were detected in beve…
7-Ketocholesterol as marker of cholesterol oxidation in model and food systems: when and how.
Cholesterol can undergo oxidation through enzymatic or chemical mechanisms, generating a wide range of oxidation products (COPs) with adverse biological effects. COPs are characterized by different functional groups and are produced in different ratios or amounts, depending on the treatment and storage conditions. To follow the cholesterol oxidation process, 7-ketocholesterol (7-KC) has been often used as an oxidation marker in both model and food systems, since it is easily formed and is one of the most representative ring COPs. However, 7-KC does not always rise with increasing time/temperature conditions, especially in complex systems and high-protein or extensively processed foods. The …
Influence of probiotic microorganisms on aflatoxins B 1 and B 2 bioaccessibility evaluated with a simulated gastrointestinal digestion
Aflatoxins (AFs) are produced mainly by the molds Aspergillus flavus and Aspergillus parasiticus. Aflatoxin B1 (AFB1) is classified as carcinogenic to humans. The aim of this study was to evaluate the capacity of different strains of Lactobacilli (Lb.) and Bifidobacteria (Bf.) to reduce the bioaccessibility of AFB1 and aflatoxin B2 (AFB2), spiked in loaf bread, using a dynamic in vitro simulated gastrointestinal digestion system. Aliquots of 20 mL of gastric and duodenal fluids were sampled for the determination of the mycotoxins gastric and duodenal bioaccessibility respectively, by liquid-chromatography coupled to the mass spectrometry in tandem (LC–MS/MS). A reduction of AFs bioacc…
Oxysterols – how much do we know about food occurrence, dietary intake and absorption?
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…
Nutriential Hazards: Micronutrients: Vitamins and Minerals
To achieve an appropriate and healthy dietary regime, it is necessary to have a balance diet with an adequate contribution of every nutrient. Micronutrients play a fundamental role for normal metabolic functioning of human body, so their deficiencies produce specific clinical manifestations as well as a wide range of non-specific physiological impairments. Under certain situations or physiological conditions (such as stress, smoking, pollution, drugs and alcohol consumption, pregnancy, lactation, etc.), nutrient requirements are even higher, being impossible to fulfill them with standard diets. In fact, over two-third of the world's population lack of one or more essential mineral elements …
Reduction of beauvericin and enniatins bioaccessibility by prebiotic compounds, evaluated in static and dynamic simulated gastrointestinal digestion
Abstract The aim of this study was to investigate the bioaccessibility of beauvericin (BEA) and enniatins (ENs) present in wheat crispy breads. A microbial fermentation was performed by a BEA- and ENs-producer Fusarium strain, adding inulin and fructooligosaccharides (FOS) at two concentrations (1% and 5%). The bioaccessibility of mycotoxins was determined by static and dynamic simulated gastrointestinal digestion systems, imitating the digestive physiological conditions until the colonic compartment. BEA and ENs were determined in the intestinal fluids by liquid chromatography-tandem mass spectrometry (LC-MS/MS). BEA and ENs bioaccessibilities in the static model (46.7–61.1% and 6.2–44.9%,…
Current and new insights on phytosterol oxides in plant sterol-enriched food.
Over the past 15 years, plant sterol-enriched foods have faced a great increase in the market, due to the asserted cholesterol-lowering effect of plant sterols. However, owing to their chemical structures, plant sterols can oxidize and produce a wide variety of oxidation products with controversial biological effects. Although oxyphytosterols can derive from dietary sources and endogenous formation, their single contribution should be better defined. The following review provides an overall and critical picture on the current knowledge and future perspectives of plant sterols-enriched food, particularly focused on occurrence of plant sterol oxidation products and their biological effects. T…
Sterol oxidation in ready-to-eat infant foods during storage.
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 (< …