Mass Transfer and Nutrient Absorption in a Simulated Model of Small Intestine

Abstract

There is an increasing need to understand how food formulations behave in vivo from both food and pharma industries. A number of models have been proposed for the stomach, but few are available for the other parts of the gastrointestinal tract. An experimental rig that simulates the segmentation motion occurring in the small intestine has been developed. The objective of developing such an experimental apparatus was to study mass transport phenomena occurring in the lumen and their potential effect on the concentration of species available for absorption. When segmentation motion was applied the mass transfer coefficient in the lumen side was increased up to a factor of 7. The viscosity of the lumen, as influenced by guar gum concentration, had a profound effect on the mass transfer coefficient. The experimental model was also used to demonstrate that glucose available for absorption, resulting from starch hydrolysis, can be significantly reduced by altering the lumen viscosity. Results suggest that absorption of nutrients could be controlled by mass transfer. Practical Application: To address health-related diseases such as obesity, novel foods that provide advanced functions are required. To achieve the full potential offered by the latest developments in the field of food material science, a fundamental understanding of the behavior of food structures in vivo is required. Using the developed gut model we have demonstrated that absorption of nutrients can be controlled by mass transfer limitations.

Impact of the degree of cooking on starch digestibility of rice – An in vitro study

“…This showed that the homogenised sample viscosity of FC was drastically changed by addition of SIF, indicating higher starch hydrolysis. The physical texture of food, such as intact grain structure, affects starch digestion and the absorption of its hydrolysis products (Singh et al, 2013;Tharakan, Norton, Fryer, & Bakalis, 2010). Thus, the digestive property of cooked rice would relate to the viscosity of its homogenised materials, which varied by cooking degree.…”

Inhibition of α-amylase activity by cellulose: Kinetic analysis and nutritional implications

“…Similarly, several studies, both in vitro and in vivo, have shown that soluble fibres such as guar gum, (1-3,1-4)-␤-d-glucan and arabinoxylan increase the viscosity of the hydrolysing medium, slowing down hydrolysis of macronutrients by impeding the enzyme-substrate interaction (Dhital, Dolan, Stokes, & Gidley, 2014;Dunaif & Schneeman, 1981;Ellis et al, 2001;Hansen & Schulz, 1982;Leeds, 1979;Montagne, Pluske, & Hampson, 2003;Taylor, 1979;Tharakan, Norton, Fryer, & Bakalis, 2010). Although Dunaif and Schneeman (1981) indicated the potential interaction between fibre source and human pancreatic enzymes, Slaughter, Ellis, Jackson and Butterworth (2002) provided the first evidence for binding of ␣-amylase to guar galactomannan and of inhibition of ␣-amylase activity through a non-competitive mechanism.…”

Dynamic responses in small intestinal mucus: Relevance for the maintenance of an intact barrier

“…In its simplest form the mucus can be considered as a maintained unstirred water layer adjacent to the mucosa across which a concentration gradient develops, in which small molecule nutrients, and indeed many drugs, diffuse across relatively unhindered [15,16]. For larger molecules and nanoscale particulates (of food or pharmaceutical origin) the situation is more complex and mucus can provide both a steric and an interactive barrier substantially reducing the absorption of these components.…”