Search results for "Bioavailability"

Availability of polyphenols in fruit beverages subjected to in vitro gastrointestinal digestion and their effects on proliferation, cell-cycle and ap…

2009

Abstract Three fruit beverages: Fb (grape–orange–apricot), FbFe (Fb + iron sulphate) and FbFeM (FbFe + skimmed milk) were subjected to in vitro gastrointestinal digestion. Addition of Fe and milk decreased the phenolic content of Fb by 13% and 55%, respectively. The digestion process decreased the phenolic content by 47%, 60%, and 70% in Fb, FbFe and FbFeM with respect to the initial, non-digested, Fb. Caco-2 cells were incubated for 4 h daily for four days or continuously for 24 h with bioaccessible fractions obtained after the digestion (digests). Polyphenols were not metabolised by Caco-2 cells. Fb digest (∼50 μM total phenolics) was the sample that led to the highest inhibition of cell …

Speciation analysis of food

2015

Bioaccessibility and bioavailability of the enniatins A, A1, B, B1 contained in a commercial wheat crispy bread

2010

Dialyzability of iron, zinc, and copper of different types of infant formulas marketed in Spain

1998

The bioavailability of trace elements in infant formulas is affected by different physiological and dietetic factors. In vitro methods based on element dialyzability have been proposed to estimate the bioavailability. Infant formulas of the same type but from different manufacturers can differ in the salt used for supplementation and in the contents of other components that can affect mineral bioavailability. The aim of our study is to estimate the dialyzability of iron, zinc, and copper of formulas marketed in Spain, in order to detect possible differences in formulas of the same type coming from different manufacturers. At the same time, the effects of the type of formula, the composition…

Calcium dialysability as an estimation of bioavailability in human milk, cow milk and infant formulas

1999

Abstract The calcium dialysability of human milk, cow milk and infant formulas is estimated by applying the in vitro method (Miller, Schricker, Rasmussen, & Van Campen, (1981). American Journal of Clinical Nutrition, 34, 2248–2256) slightly modified, as a measure of its bioavailability. The influence of the protein composition of infant formula samples on calcium bioavailability is also studied. Whole cow milk, a pool of human milk and 18 commercial infant formulas of 6 different types are analysed. The highest values of calcium dialysability (mg Ca/100 ml infant formula) correspond to premature (13.6) and follow-up formulas (11.8) and the lowest ones to adapted formulas (3.7); the latter v…

Intestinal absorption enhancement via the paracellular route by fatty acids, chitosans and others: a target for drug delivery.

2005

Peroral delivery of hydrophilic drugs is one of the greatest challenges in biopharmaceutical research. Hydrophilic drugs usually present low bioavailability after oral administration. One of the causes of this low bioavailability is their poor intestinal permeation through the paracellular pathway. This pathway is actually restricted by the presence of tight junctions at the apical side of the enterocytes. In the last few years, great interest has been focused on the structure and cellular regulation of tight junctions, materializing in more in-depth knowledge of this intestinal barrier. Simultaneously, and on the basis of this understanding, continuous efforts are being made to develop age…

Effects of elevated production of autochthonous dissolved organic matter on the freely dissolved concentration of cadmium

2018

Eutrophication enhances the production of autochthonous dissolved organic matter (DOM), which is a major driving factor behind the impairment of many aquatic ecosystems. In a mesocosm study, we investigated the effects of the abundance and composition of DOM on the potential bioavailability of cadmium (Cd) caused by eutrophication, using three-dimensional excitation-emission matrix fluorescence spectroscopy integrated with tangential flow ultrafiltration technology. The complexing capacity of DOM-Cd and the sorption distribution coefficient between DOM and the bulk solution was calculated based on a 1 : 1 complexation model. The fluorescent DOM was decomposed into three components (one prot…

Spray Freeze Dried Lyospheres® for Nasal Administration of Insulin

2021

Pharmacologically active macromolecules, such as peptides, are still a major challenge in terms of designing a delivery system for their transport across absorption barriers and at the same time provide sufficiently high long-term stability. Spray freeze dried (SFD) lyospheres® are proposed here as an alternative for the preparation of fast dissolving porous particles for nasal administration of insulin. Insulin solutions containing mannitol and polyvinylpyrrolidone complemented with permeation enhancing excipients (sodium taurocholate or cyclodextrins) were sprayed into a cooled spray tower, followed by vacuum freeze drying. Final porous particles were highly spherical and mean diameters r…

In Vitro and In Silico Studies of Two 1,4-Naphthoquinones and Their Topical Formulation in Bigels.

2021

Background: 1,4-Naphthoquinones (1,4-NQs) are secondary plant metabolites with numerous biological activities. 1,4-NQs display low water solubility and poor bioavailability. Bigels are a new technology with great potential, which are designated as drug delivery systems. Biphasic bigels consisting of solid and liquid components represent suitable formulations improving diffusion and bioavailability of NQs into the skin. Objective: We evaluated the in silico and in vitro activity of 5,8-dihydroxy-1,4-naphthoquinone (M1) and 2,3-dichloro-5,8-dihydroxy-1,4-naphthoquinone (M2) on elastase and assessed their cytotoxicity towards COLO38 melanoma cells. The 1,4-NQs were loaded into bigels for topi…

Multicomponent solid dispersion as a formulation strategy to improve drug permeation: A case study on the anti-colorectal cancer irinotecan

2019

Abstract Multicomponent solid dispersions (MSD)s are frequently proposed as efficient drug delivery systems to improve drug solubility and bioavailability. In this study, the effects of specific excipients, such as mannitol, inulin, poly(methyl methacrylate-co-methacrylic)acid (PMMA) and cellulose acetate phthalate (CAP) have been tested to potentially improve irinotecan (IRN) permeation in the intestinal tract with the intention to protect the drug from the gastric environment. MSDs were formulated as microparticles by Spray-Drying technique. Raw materials and microparticles have been characterized by FTIR analysis to determine hydrogen bonding. SEM images were recorded to investigate morp…