Lipids Fatty Acids Carboxyl group Saturated Fatty Acids CH3 CH2 n COOH straight chain hydrocarbons terminate in a carboxyl group make up complex lipids generally insoluble in water important source of energy dietary and storage used in the cell membrane lipid bilayer and MPL supply essential fatty acids synthesis of hormones absorption of fat soluble vitamins increase the palatability of feed BUT too much lipid can decrease the palatability of feed contains no carbon carbon double bonds contain all of the hydrogens they can possibly contain Unsaturated Fatty Acids Oil Fat Fatty Acid Nomenclature contain one or more carbon carbon double bonds missing 2 H per double bond the double bonds can either be cis or trans liquid at room temperature has more double bonds solid at room temperature very few double bonds the omega system makes the assumption that double bonds are separated by 3 carbons example nomenclature below Omega Naming System Delta Naming System Triacylglycerol Triglycerides Lingual Lipase starts counting from the methyl end of the fatty acid assumes that double bonds are separated by 3 carbons starts counting from the carboxyl end of the fatty acid how we store lipids approximately 95 of the lipids we consume humans pigs are TAGs mammalian enzyme produced by the salivary glands produced continuously production increases with increased fat intake stable and active in the low pH of the stomach act on the short chain FA at the Sn3 position in the mouth and the stomach of non ruminants Gastric Lipase Emulsification Physical Emulsification Chemical Emulsification mammalian enzyme produced by chief cells in the stomach produced continuously production increases with increased fat intake stable and active in the low pH of the stomach act on the short chain FA at the Sn3 position in the stomach of nonruminants increase the surface area of a fat droplet by turning it into many small fat droplets mixing that occurs in the stomach and as food enters the duodenum occurs in the proximal small intestine bile is mixed with digesta at the duodenum Bile Colipase Pancreatic Lipase Micelle made in the liver stored in the gall bladder synthesized from cholesterol has both a hydrophobic region and a hydrophilic region allowing it to interact with hydrophobic lipids and the aqueous environment produced by the pancreas in the inactive form procolipase procolipase is activated to colipase by trypsin colipase contains a hydrophobic region that interacts with the fat droplet colipase is NOT an enzyme it just creates a binding site for pancreatic lipase mammalian enzyme hydrolyzes fatty acids from Sn1 and Sn3 positions requires colipase for optimal activity fat droplet that contains FFA and MAG with the FA at Sn2 cholesterol A D E and K micelles formed in bile acid allow for transport across the apical membrane into the enterocyte AcylCoA Synthetase Chylomicron B 48 Adsorb enzyme that reforms TAG in the enterocyte complete fat particle exocytosed into lymphatic circulation and then slowly moves into the blood stream 82 TAG 7 phospholipid 2 cholesterol 9 protein and some A D E and K apolipoprotein stabilizes the lipoprotein as it moves through circulation confers specificity like a name tag which tells the liver to leave it alone enables lipoprotein lipase to hydrolyze TAG into DAG and FFA on the surface of muscle and adipose cells to become stuck to Desorb Phospholipids Glycolipid Lysolecithin become released from xfound in grasses and plants contains a sugar at Sn1 primary lipid source in grazing animals primary source of lipids digested in the small intestine of ruminants can come from microbes MPL desorbs saturated fatty acids from feed particles Lipase Phospholipase What is this a structure of Galactolipase microbial enzyme that hydrolyzes TAG into glycerol and 3 FFA microbial enzyme that hydrolyzes phospholipids into glycerol 2 FFA and the polar head group microbial enzyme that hydrolyzes glycolipids into glycerol 2 FFA and sugar Phospholipid What is this a structure of What is this a example of What is this a structure of What is this a example of Glycolipid Chemical Emulsification Structure of a Triacylglycerol Fatty Acid Nomenclature What is this a structure of What is this a example of Saturated vs Unsaturated Fatty Acids Fatty Acid Structure
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