Interaction of a Dietary Fiber (Pectin) with Gastrointestinal Components (Bile Salts, Calcium, and Lipase): A Calorimetry, Electrophoresis, and Turbidity Study

Abstract

An in vitro gastrointestinal model consisting of oral, gastric, and intestinal phases was used to elucidate the impact of pectin on the digestion of emulsified lipids. Pectin reduced the extent of lipid digestion, which was attributed to its binding interactions with specific gastrointestinal components. The interaction of pectin with bile salts, lipase, CaCl2, and NaCl was therefore investigated by turbidity, microstructure, electrophoresis, and isothermal titration calorimetry (ITC) at pH 7.0 and 37 °C. ITC showed that the interaction of pectin was endothermic with bile salts, but exothermic with CaCl2, NaCl, and lipase. Electrophoresis, microstructure, and turbidity measurements showed that anionic pectin formed electrostatic complexes with calcium ions, which may have decreased lipid digestion due to increased lipid flocculation or microgel formation because this would reduce the surface area of lipid exposed to the lipase. This research provides valuable insights into the physicochemical and molecular mechanisms of the interaction of pectin with gastrointestinal components that may affect the rate and extent of lipid digestion.

Impact of pectin properties on lipid digestion under simulated gastrointestinal conditions: Comparison of citrus and banana passion fruit (Passiflora tripartita var. mollissima) pectins

“…An increase in the number of non-polar groups may lead to increased binding of bile salts through hydrophobic attraction (Dongowski, 1995;EspinalRuiz, Parada-Alfonso, Restrepo-S anchez, Narv aez-Cuenca, & McClements, 2014;Wilde & Chu, 2011). The binding of bile salts by pectin may retard lipid digestion because they can no longer interact with the fat droplet surfaces (thereby inhibiting lipase adsorption) or because they can no longer solubilize FFAs generated at the fat droplet surfaces and thereby, inhibiting lipase activity (Espinal-Ruiz, Parada-Alfonso, Restrepo-S anchez, et al, 2014). An increase in methoxylation would therefore be expected to decrease the rate of lipid digestion through this effect (Reis et al, 2009).…”

Enhancing Nutraceutical Performance Using Excipient Foods: Designing Food Structures and Compositions to Increase Bioavailability

“…Polysaccharides may also form impermeable coatings around certain food components (such as lipid droplets) thereby inhibiting their digestion and the subsequent liberation of bioactive agents (McClements and others ; Tokle and others ). Ionic polysaccharides may bind oppositely charged molecular species, thereby altering their normal function in the digestion process (Espina‐Ruiz and others ). For instance, cationic polysaccharides (such as chitosan) may bind anionic bile salts, free fatty acids, or phospholipids, whereas anionic polysaccharides (such as alginate) may bind cationic calcium ions (Fave and others ; Armand ; McClements and others ; Tzoumaki and others ).…”

Estudio del efecto fisiológico del consumo de arepas enriquecidas con pectina extraída de la cáscara de curuba (Passiflora tripartita var. mollissima)

“…Allí se encontró que todas las enzimas fueron inhibidas de manera parcial, siendo la lipasa pancreática la más afectada por las pectinas. En el estudio mencionado también se halló que un mayor grado de metoxilación está relacionado con un mayor poder inhibitorio de las pectinas sobre las enzimas mencionadas (20).…”

“…Lo anterior, debido a que se estableció que las pectinas con peso molecular menor a 230 kDa y grado de metoxilación mayor a 60% mol/mol (moles de metil éster/100 moles de ácido urónico), favorecen la inhibición de la actividad de la lipasa pancreática (20).…”