Digestion of fats

A significant fraction of the body s cholesterol is used to form bile acids Oxidation m the liver removes a portion of the CsHi7 side chain and additional hydroxyl groups are intro duced at various positions on the steroid nucleus Cholic acid is the most abundant of the bile acids In the form of certain amide derivatives called bile salts, of which sodium tau rocholate is one example bile acids act as emulsifying agents to aid the digestion of fats... 

As we have seen in this chapter steroids have a number of functions in human physiology Cholesterol is a component part of cell mem branes and is found in large amounts in the brain Derivatives of cholic acid assist the digestion of fats in the small intestine Cortisone and its derivatives are involved in maintaining the electrolyte balance in body fluids The sex hormones responsible for mascu line and feminine characteristics as well as numerous aspects of pregnancy from conception to birth are steroids... 

Bile acid sequestrants may interfere with die digestion of fats and prevent die absorption of die fat-soluble vitamins (vitamins A, D, E, and K) and folic acid. When die bile acid sequestrants are used for long-term therapy, vitamins A and D may be given in a water-soluble form or administered parenterally. If bleedingtendencies occur as die result of vitamin K deficiency, parenteral vitamin K is administered for immediate treatment, and oral vitamin K is given for prevention of a deficiency in the futum... 

The answer is d. (Hardman, p 935.) Pancrelipase is an alcoholic extract of hog pancreas that contains lipase, trypsin, and amylase. It is effective in reducing the steatorrhea of pancreatic insufficiency None of the other drugs mentioned have significant action in the digestion of fats... 

Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile adds and salts, cholesterol, and electrolytes. It aids digestion of fats in the duodenum. [NIH]... 

Bile acids derivatives of cholesterol that facilitate the digestion of fats and oils. 

The digestion of fat produces chylomicrons and VLDL - metabolism of the latter produces LDL, high concentrations of which increase the risk of development of atherosclerosis (Appendix 11.3) (Chapter 22). 

Pancreatic enemies (B) from slaughtered animals are used to relieve excretory insufficiency of the pancreas ( disrupted digestion of fats steatorrhea, inter alia). Normally, secretion of pancreatic enzymes is activated by cholecystokinin ancreozymin, the en-terohormone that is released into blood from the duodenal mucosa upon contact with chyme. With oral administration of pancreatic enzymes, allowance must be made for their partial inactivation by gastric acid (the lipases, particularly). Therefore, they are administered in acid-resistant dosage forms. 

The separation of oil and water (B) can be prevented by adding a strongly amphipathic substance. During shaking, a more or less stable emulsion then forms, in which the surface of the oil drops is occupied by amphipathic molecules that provide it with polar properties externally. The emulsification of fats in food by bile acids and phospholipids is a vital precondition for the digestion of fats (see p.314). 

Bile is an important product released by the hepatocytes. It promotes the digestion of fats from food by emulsifying them in the small intestine (see p. 2770). The emulsifying components of bile, apart from phospholipids, mainly consist of bile acids and bile salts (see below). The bile also contains free cholesterol, which is excreted in this way (see p. 312). 

The liver and the pancreas are not part of the digestive tract as such, but they provide enzymes and secretions required for digestion to occur in the small intestine. The pancreas secretes amylase, lipase, and nuclease enzymes, as well as several enzymes involved in breaking down proteins and peptides. As discussed below with digestion of fats, the liver secretes a substance called bUe that is stored in the gallbladder and then secreted into the duodenum when needed for digestion of fats. 

A special consideration in the digestion of fats is that they are not water soluble and cannot be placed in aqueous solution along with the water-soluble lipase digestive enzymes. However, intimate contact is obtained by emulsification of fats through the action of bile salts from glycocholic and taurocholic acids produced from cholesterol in the liver ... 

What is the fundamental difference between the digestion of fats and that of complex carbohydrates (starches) and proteins What role is played by bile salts in the digestion of fats ... 

Partially hydrolyzed lecithins exhibit enhanced oil-in-water emulsifying properties, particularly in the presence of calcium and magnesium ions. They do not lose their emulsifying action in the presence of calcium and magnesium ions as rapidly as do the unmodified types. Enzymatically modified lecithins have been used in calf milk replacement formulations to improve the emulsification and digestibility of fats (56). 

In addition to the use of new oils, significant advances were made in the manufacturing process. Peptic digestion of fat and the use of udder extracts soon were... 

Emulsification greatly increases the surface area of the fat and this is an essential requisite for digestion of fat in the intestine. 

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