On the role of bile salts in the digestion of emulsified lipids

Abstract

20The objective of this study was to understand quantitatively the role that bile salts 21 play in the digestion of emulsified lipids. The behaviours of digestion by pancreatin (1.6 22 mg/mL) of sodium-caseinate-stabilized emulsions (0.5 wt% protein) and bile-extract-23 stabilized emulsions (0.2 5 mg/mL) as influenced by the addition of aqueous bile extract 24were studied under simulated intestinal conditions (37 °C; pH 7.5; 39 mM K2HPO4, 150 mM 25 NaCl; with continuous agitation at ~ 150 rev/min for 3 h). The droplet characteristics (size 26 and -potential) of the sodium caseinate-and bile extract-stabilized droplets were evaluated 27 by light scattering techniques. The kinetics of the total fatty acids released by hydrolysis of 28 the emulsified lipids was monitored by the pH-stat method with or without the presence of 29 continuous phase bile extract. The results suggested that the presence of unadsorbed bile 30 extract markedly enhanced the rate and the extent of lipid digestion. This could be attributed 31 to considerable removal of lipolysis products (free fatty acids, mono-and/or di-acylglycerols) 32 in mixed micelles, which are known to inhibit lipid digestion, by the unadsorbed bile salts. 33This study provides new insights for the lipid digestion of food formulations. 34 35

Effect of Gum Arabic, Gum Ghatti and Sugar Beet Pectin as Interfacial Layer on Lipid Digestibility in Oil-in-Water Emulsions

“…In addition, the surface-active bile salts were capable of assisting lipolysis due to fully or partially displacing the emulsifier from the oil-water interface [15,18]. Bile salts are a very peculiar type of biosurfactant, and their facial amphilicity originates from the flat steroidal structure, with the polar hydroxyl groups on the concave side and methyl groups on the convex side [19]. Bile salts play a crucial role in lipid digestion by displacing initial adsorbed materials from the interface and permitting lipase/colipase complexes to act on the bile salts coated oil droplets.…”

“…The interafcial layer adsorbed with Pluronic F68 is more resistant to bile salts adsorption than that with phospholipids Epikuron 145 V [12]. The unadsorbed bile salts in aquenous phase could markedly enhance the rate and the extent of lipid digestion, due to considerable removal of lipolysis products (free fatty acids, mono-and/or di-acylglycerols) through mixed micelles formed with the unabsorbed bile salts [19]. In summary, the interfacial engineering approaches have potential for designing the emulsion-based delivery system to modify the lipid digestibility in the gastrointestinal tract, which may promote satiety and satiation [22].…”

Composite whey protein–cellulose nanocrystals at oil-water interface: Towards delaying lipid digestion

“…in the upper 60 part of the small intestine in healthy human adults. Lipid digestion is essentially an 61 interfacial process that involves complex adsorption phenomenon of lipase/colipase 62 and bile salts onto the surface of the oil droplets (Sarkar, Ye, & Singh, 2016c;Singh 63 & Sarkar, 2011). Bile salts are bio-surfactants that competitively push out the 64 interfacial materials originally present at the surface, facilitating the adsorption of 65 pancreatic lipase-colipase complex and subsequent lipolysis (Maldonado-Valderrama, 66…”

Synthesis, physicochemical properties, and health aspects of structured lipids: A review

“…Natural proteins have been widely used as effective emulsifiers to obtain physically stable O/W emulsions, but they are less effective in delaying lipolysis upon consumption. Protein-based emulsifiers may undergo proteolysis when they travel through the gastric intestinal tract (GIT) and moreover, they can also be easily displaced by surface-active bile salts in the small intestine (Sarkar, Horne, & Singh, 2010;Sarkar, Ye, & Singh, 2016;Singh & Sarkar, 2011). In contrast, Pickering emulsions stabilized by various edible particles, such as cellulose nanocrystals (Bai et al, 2019;Liu, Kerr, & Kong, 2019) and cellulose nanofibers (Winuprasith et al, 2018), have been found to be better at delaying lipid digestion.…”