The efficacy of orally ingested bioactives relies in most instances on their bio-accessibility and bio-availability1. This talk will provide an evidence-based overview on how polysaccharides can be physically and chemically modulated to achieve altered functionalities and tweak the digestive fate of bioactive proteins and emulsions.
The first part will focus on resistant starch as an indigestible carbohydrate whose thermal processing can be used to delineate its prebiotic activity, shifting the gut microbiome and luminal contents towards healthier ones2. Second, the mechanisms behind the ability of dextrins, pectins and alginate to alter emulsion responsiveness to gastrointestinal conditions will be discussed3, 4. The third part will focus on the electrostatic surface deposition of anionic polysaccharides, namely carrageenans, as means to decrease protein susceptibility to gastric and duodenal proteolysis5. Advanced colloid characterizations (e.g. using AFM) will be linked to analyses of chyme produced duringin vitrohuman digestion. These will also demonstrate potential deleterious effects to intestinal epithelia (using a Caco-2 cell model), namely on the tight junction barrier properties and truncation of the cellular actin skeleton.
Overall, the talk will provide mechanistic insights pertinent to rational design of oral formulations with controlled lipid digestion, effective delivery of bioactives and ultimately promoting human health and well-being.
1. R. C. Benshitrit, C. S. Levi, S. L. Tal, E. Shimoni and U. Lesmes,Food and Function, 2012,3, 10-21.
2. U. Lesmes, E. J. Beards, G. R. Gibson, K. M. Tuohy and E. Shimoni,Journal of Agricultural and
Food Chemistry, 2008,56, 5415-5421.
3. U. Lesmes and D. J. McClements,Food Hydrocolloids, 2012,26, 221-230.
4. T. Tokle, U. Lesmes, E. A. Decker and D. J. McClements,Food & Function, 2012,3, 58-66.
5. T. David-Birman, A. Mackie and U. Lesmes,Food Hydrocolloids, 2013,31, 33–41.
