Abstract
Digestion of dietary fat first takes place in the stomach in numerous species including humans. Thus, we have studied in vitro the gastric lipase-catalyzed hydrolysis of four emulsions devoted to tube feeding. The emulsions contained phospholipids, sugar-esters, and triglycerides in the form of either medium-chain triglycerides (MCT) or long-chain triglycerides (LCT) or a 1 4 (wt/wt) mixture of both (MCT/LCT). The mean droplet sizes were 0.19 μm (MCT), 0.43 μm (LCT), and 0.46 μm or 3.18 μm (MCT/LCT). Gastric lipase activity was greater on the fine mixed emulsion than on the coarse one, but enzyme affinities and bindings onto droplets were comparable. The affinity of gastric lipase was higher for LCT emulsion. Free fatty acid concentration played a key role in the progressive inhibition of lipolysis, the extent of which was dependent on the emulsion surface area. Prehydrolyzing emulsions by gastric lipase helped pancreatic lipase binding to the fine droplets and enhanced the subsequent activity of pancreatic enzyme. Relevant implications of nutritional importance can be drawn concerning lipolysis in the stomach, such as (1) suitability of mixed emulsions, (2) key role of the nature of triglycerides, (3) apparent advantage of small droplet size (0.4 versus 3 μm), and (4) potential detrimental effect of free fatty acids present in emulsions to be tube fed in the stomach, especially in patients with reduced pancreas capacity. ( J. Nutr. Biochem. 5:124–133, 1994.)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.