Emulsification lipolysis

The digestion of triacylglycerols in adult nonruminant mammals has been described as initiated in the mouth by hngual lipase released in the sahva at the base of the tongue (52). Up to 6% of the fatty acids are hydrolyzed and initiate emulsion formation in the stomach. The digesta (called chyme at this location) is released from the stomach slowly into the duodenum to ensure complete mixing with the bile salts and emulsification. Lipolysis occurs by association of pancreatic lipase and co-lipase at the surface of the bile salt-stabihzed emulsion. Amphipathic molecules (fatty acids, sn-2 monoacylglycerols, and lysolecithins) are produced and associate with the bile salts to form water-soluble micelles from which absorption occurs. 

Pasquier B, Armand M, Guillon F, Castelain C, Borel P, Barry JL, Pieroni G and Lairon D. 1996. Viscous soluble dietary fibers alter emulsification and lipolysis of triacylglycerols in duodenal medium in vitro. J Nutr Biochem 7 293—302. 

The inhibitor was previously dissolved at various concentrations into the hpid substrate before its emulsification under vigorous stirring in a lipolysis vessel (Fig. 9.5D). Lipase was then added and its activity was continuously recorded. 

Pasquier, B., Armand, M., CasteUan, C., GuiUon, F., Borel, P., Lafont, H., and Lairon, D. (1996). Emulsification and lipolysis of triacylglycerols are altered by viscous soluble dietary fibres in acidic gastric medium in vitro. Biochem. J. 314, 269-275. 

Dispersibility tests Dye tests Liquefaction time Robustness to Dilution In vitro lipolysis studies Characterization of self-emulsification efficiency of liquid SNEDDS Characterization of self-emulsification efficiency of solid SNEDDS pellets Characterization of solid SNEDDS as time equired for melting under in vivo conditions Determine the capability of the formulation to withstand possibly infinite dilutions Estimation of lipolysis rate and amount of lipid digestion... 

Hydrolysis of esterified lipids is essential in order for lipid absorption to occur. Anatomically, lipolysis begins in the stomach where a limited amount of partial hydrolysis of triglycerides provides more polar lipids (fatty acids and partial glycerides) to assist in emulsification. A lingual lipase is thought to be involved in this process. The net result of this gastric phase of fat digestion is the initiation of lipolysis and the preparation of a stable emulsion on which the major pancreatic lipolytic enzymes can act in the milieu of the small intestine. 

Vitamin E, an apolar molecule that is the most important lipid-soluble antioxidant in humans, is not synthesized in our body, but it is acquired by nourishment. Vitamin E is emulsified together with the fat-soluble components of the food and transported in the body. Lipolysis and emulsification of the formed lipid droplets then lead to the spontaneous formation of mixed micelles [61]. 

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