Simulated Gastric and Intestinal Fluid Electrolyte Solutions as an Environment for the Adsorption of Apple Polyphenols onto β-Glucan

• Published in: Molecules (Basel, Switzerland) Switzerland), 2022-10, Vol.27 (19), p.6683
• Main Authors: Jakobek, Lidija, Strelec, Ivica, Kenjerić, Daniela, Šoher, Lidija, Tomac, Ivana, Matić, Petra
• Format: Article
• Language: English
• Subjects: Acids; Adsorbents; Adsorption; adsorption capacity; Apples; Chlorogenic acid; Colon; Dietary fiber; Digestive system; Electrolytes; Fibers; Flavonols; Fruits; Gastrointestinal system; Gastrointestinal tract; Glucan; High performance liquid chromatography; Intestine; Liquid chromatography; Metabolites; Oxidation; Phenolic acids; phenolic compounds; Phenols; Polyphenols; β-Glucan
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27196683

Interactions with dietary fibers in the gastrointestinal tract might affect the potential bioactivities of phenolic compounds. In this study, the interactions between apple phenolic compounds and β-glucan (a dietary fiber) were studied by studying the adsorption process in simulated gastric and intestinal fluid electrolyte solutions. Phenolic compounds were extracted from apples, adsorbed onto β-glucan (2 h, 37 °C, in gastric or intestinal fluid electrolyte solutions), and determined using high performance liquid chromatography. Phenolic compounds (flavan-3-ols, flavonols, phenolic acids, and dihydrochalcone) were stable in the gastric fluid (pH 3). In the intestinal fluid (pH 7), flavan-3-ols were not found and chlorogenic acid isomerized. Polyphenols from the apple peel (up to 182 and 897 mg g−1) and flesh (up to 28 and 7 mg g−1) were adsorbed onto β-glucan in the gastric and intestinal fluids, respectively. The adsorption was affected by the initial concentration of the polyphenols and β-glucan and by the environment (either gastric or intestinal fluid electrolyte solution). By increasing the initial polyphenol amount, the quantity of adsorbed polyphenols increased. Increasing the amount of β-glucan decreased the amount adsorbed. The results can be helpful in explaining the fate of phenolic compounds in the gastrointestinal tract.