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Dr . N. Sivaranjani
Asst. Prof
Dr. N.Sivaranjani
• Major dietary lipids are Triacyl glycerol -90%,
Cholesterol
Cholesteryl esters &
Phospholipids
 Indian diet contains about 20-30 g of lipids per
day.
Western diet – 2 or 3times more than this
quantity
Dr. N.Sivaranjani
• Animal foods – Diary products like Milk, Butter,
Ghee, Cheese, Meat , Fish and Eggs
• Plant foods – Vegetable cooking oil – Ground nut
oil, Sunflower , Palm ,Rice bran ,Coconut , Cotton
seed oil.
• Vegetable fat are of better quality compared to
animal fats – high PUFA content.
• Although rich in UFA , chance of deterioration
are low because of presence of Antioxidants in
them. Dr. N.Sivaranjani
Ingestion of fatty food
Enterogastrone (CCK & Secretin) from duodenum
• Gastric motility & retards discharge of food bolus
This Delays the rate of emptying of stomach
• Fatty food have the ability to satisfy hunger.
Alcohol intoxication can be avoided if consumed after
ingestion of fatty food. (eg- Milk, Cream)
_
+
Dr. N.Sivaranjani
• Lingual lipase –
• Originates from glands at the back of the tongue
• Acts of TAG containing fatty acids of short- or
medium-chain length
• SCFA are present in milk, butter and ghee.
• MCFA – mother’s milk and coconut oil.
• Optimum pH of 2.5-5 - Continues to be active in
the stomach. Dr. N.Sivaranjani
Gastric lipase / Acid stable lipase (pH-5.4)
• secreted by chief cells, the secretion is
stimulated by Gastrin.
• Requires presence of Ca2+
• Up to 30% digestion of TAG occurs in stomach
• Acts only on SCFA- milk, butter, ghee
• Clinical importance :- Lipid digestion in neonates
• Milk fat is the primary source of calories in
neonates.
Dr. N.Sivaranjani
Human milk contains specific Lipase which is
activated by bile salts in duodenum
• Bile salt activated lipase – completely hydrolyses
TAG of milk fat.
• Premature infants – secretary function of
pancreas is not fully established at birth.
So depends only on these lipases.
In pancreatic insufficiency – SCFA and MCFA
are therapeutically used in malabsorption
syndromes.
Dr. N.Sivaranjani
• phenomenon of dispersion of lipids into smaller
droplets (200-5000nm) due to reduction in the
surface tension
Importance :
• Pre- requisite / essential for digestion of lipids
• Increases the surface area of the hydrophobic
lipid droplets
• Digestive enzymes can act effectively
Dr. N.Sivaranjani
Dr. N.Sivaranjani
 Emulsification is favored by
 Bile salts – detergent action
 Phospholipids – Surfactant action
 Peristalsis - mechanical mixing
Dr. N.Sivaranjani
• Synthesized from cholesterol in the liver as bile
acids.
• At physiological pH, the bile acids are mostly
present as anions.
• Na2+ and K+ salts of Glyco-cholate, Glyco-
Chenodeoxycholate, Tauro-cholate, Tauro-
Chenodeoxycholate.
• They are secreted with bile, into the duodenum.
Dr. N.Sivaranjani
• Most effective biological emulsifying agent
• Helps in digestion and absorption of lipids
• stabilize the smaller particles by preventing
them from coalescing.
Emulsification Micelle formation
Dr. N.Sivaranjani
Taurine
Dr. N.Sivaranjani
• CCK –
• sec. of panc. E
GB to release Bile
into the duodenum
Gastric motility
• Secretin –
• sec. of HCO3
to provide appropriate pH for
pancreatic enzymes
+
+
_
+
Dr. N.Sivaranjani
• Pancreatic lipase – TAG
• Cholesterol esterase - Cholesteryl esters
• Phospholipase A2 - Phospholipids
Dr. N.Sivaranjani
• Pancreatic lipase
• Alkaline pH (pH-7.7) is favorable for the action of
pancreatic enzymes
• removes the fatty acids of TAG, at carbons 1 & 3
Importance :
• Cystic fibrosis - Pancreatic insufficiency leads to
Significant Malabsorption of fat
Dr. N.Sivaranjani
Triacylglycerol
R2-C-O-CH
CH2-O-C-R3
CH2-O-C-R1
O
=
O
=
O
=
R2-C-O-CH
CH2-OH
CH2-O-C-R1
O
=
O
=
Diacylglycerol
R2-C-O-CH
CH2-OH
CH2-OHO
=
2-Monoacylglycerol
1-MonoacylglycerolGlycerol
HO-CH
CH2-OH
CH2-O-C-R2
O
=
HO-CH
CH2-OH
CH2-OH
FFA
R3-COOH
R1-COOH
R2-COOH
P. lipase
P.lipase
P.lipase
Isomerization
Co-lipase
Dr. N.Sivaranjani
The major end products of the digestion of TAG :
2-MAG (78%),
1-MAG (6%),
Glycerol and FFA (14%).
Dr. N.Sivaranjani
Colipase
• secreted by the pancreas as a zymogen
• activated in the intestine by Trypsin
• binds with the lipase at a ratio of 1:1
• Colipase binds at the lipid-aqueous interface
and helps to anchor and stabilize lipase to its
substrate TAG.
• Enterostatin – acts as satiety signal for lipids.
Procolipase
Colipase
5 a.a Enterostatin
Trypsin
Dr. N.Sivaranjani
Activity of the enzyme is increased in the
presence of bile salts
Pancreatic Cholesterol ester hydrolase
or Cholesterol esterase
Dr. N.Sivaranjani
R2-C-O-CH
CH2-O-P-N-base
CH2-O-C-R1
O
=O
=
HO-CH
CH2-O-P-N-base
CH2-O-C-R1
O
=
Glycerophospholipid Lysophospholipid
Fatty acid
H2O R2-COOH
Phospholipase-A2
requires bile salts for optimum activity
Enzyme is secreted as Zymogen form and activated by
Trypsin
Dr. N.Sivaranjani
Lysolecithin or
Dr. N.Sivaranjani
• C2 FA-is frequently Arachidonic acid in cell
membrane – synthesis of Eicosinoids
• Lysolecithin - is a detergent and hemolytic agent.
• The Phospholipase-A2 enzyme is present in the venom
of viper snakes.
• In viper poisoning -hemolysis and consequent renal
failure is seen.
Dr. N.Sivaranjani
R2-C-O-CH
CH2-O-P-O-C-C-N-CH3
CH2-O-C-R1O
=
Glycerophospholipid
Site of action of phospholipases
O
=
O
=
O
CH3
CH3H2H2
Phospholipase-A1
Phospholipase-A2
Phospholipase-D
Phospholipase-C
+
Dr. N.Sivaranjani
• Micelles are molecular aggregate, having a disk /
spherical shape containing :
Interior (hydrophobic) – 2 MAG, LCFA,
cholesterol & phospholipids (hydrophobic part)
Exterior (hydrophilic) - bile salts and
hydrophilic part of cholesterol and PL.
• SCFA & MCFA do not require the assistance of
mixed micelles for absorption by the intestinal
mucosa.
Dr. N.Sivaranjani
Bile salts are reabsorbed in lower part of SI and return
to the liver by portal vein for resecretion into bile –
Enterohepatic circulation
Dr. N.Sivaranjani
Mixed micelles serve as the major vehicles for
the Absorption of lipids from the intestinal
lumen to the intestinal cells
Essential for the absorption of fat-soluble
vitamins such as vitamin A, D and K.
Dr. N.Sivaranjani
• Digestion – Emulsification
by bile salts,
pancreatic enzymes
• Absorption – by micelle
formation with bile salts
• Post-absorption –
re-esterification inside
Intestinal cells
• Transport – chylomicrons
Transport
Dr. N.Sivaranjani
Long chain
Fatty acids
2-MAG
Cholesterol
Short chain
Fatty acids
& glycerol
Portal circulation Lymphatic system
Blood
Peripheral tissues
Thiokinase
Carried by Albumin
Re-esterification Inside the Intestinal mucosal
Cell
Dr. N.Sivaranjani
Interior (hydrophobic) –
2 MAG, LCFA, cholesterol
& Phospholipids
Exterior (hydrophilic) - bile
salts and hydrophilic part
of cholesterol and PL
Chylomicrons composed of:
Triacylglycerols (85-90%)
Cholesterol & ChE (5%)
Phospholipids (7%)
Apolipoprotein-B48 (1-2%)
ApoB48
Dr. N.Sivaranjani
• Lipids that are resynthesized in the intestinal
cells are hydrophobic in nature, so surrounded
by Apolipoproteins (apoA and B-48) and
phospholipids at the exterior to form
Chylomicrons.
• This formation stabilizes the droplets and
increases their solubility.
Dr. N.Sivaranjani
The chyle (milky fluid) from the intestinal
mucosal cells loaded with chylomicrons are
transported through the lacteals into the
thoracic duct and then emptied into lymph
circulation.
Postprandial Lipemia - The serum may appear
milky after a high fat meal due to the presence
of chylomicrons in circulation.
Normally the lipemia clears within a few hours
by the uptake of chylomicrons by tissues by LPL
(lipoprotein lipase enzyme) .
Dr. N.Sivaranjani
Lipemia sample
Dr. N.Sivaranjani
• Fate of the Chylomicrons:
• Chylomicrons are the transport form of dietary
triglycerides from intestines
• Adipose tissue - storage
• Muscle and Heart - for their energy needs.
Dr. N.Sivaranjani
• Fate of free fatty acids –
• Carried by Albumin
• Taken by Muscle or Adipocytes,
• Oxidized to produce energy
• Fate of glycerol –
• Taken by liver to produce glycerol 3-phosphate
• Which enters Gluconeogenesis / Glycolysis or
used for TAG / PL synthesis in liver.
Dr. N.Sivaranjani
Abnormalities in lipid digestion &
absorption
Dr. N.Sivaranjani
Steatorrhoea – Greek word, "stear", means fat
large amount of fat or FA excreted in feces >6g  day.
Most common cause :
Defective digestion - Pancreatic enzyme deficiency
– pancreatitis  cystic fibrosis
Defective absorption – Celiac disease, Surgical
removal of intestine, Bile salt deficiency – liver
disease  obstruction in bile duct due to gall stones or Ca head
of pancreas.
Defective chylomicron synthesis – congenital
abetalipoproteinemia – defect in ApoLP synthesis.Dr. N.Sivaranjani
In pancreatic deficiency:
unsplit fat is present in
stools.
When bile is not available -
Absorption is defective;
split fat is present in stools;
defective absorption of
vitamin K leads to prolonged
prothrombin time.
Dr. N.Sivaranjani
Pancreatin / Enzyme Supplements -Trypsin + Lipase
Steatorrhea – Rx
Dr. N.Sivaranjani
• Chyluria - Abnormal connection b/w urinary tract
& lymphatic drainage system of intestine.
• Urine appears milky due to lipid droplets.
• Chylothorax - Abnormal connection b/w the pleural
cavity and thoracic duct - Milky pleural effusion.
Dr. N.Sivaranjani
Drugs used in Obesity
• Orlistat is a powerful inhibitor of pancreatic
lipase,hence prevents fat digestion and absorption.
• Olestra is a synthetic lipid, produced by
esterification of natural fatty acids with sucrose
(instead of glycerol).
Olestra tastes like a natural lipid.
However, it cannot be hydrolysed and therefore,
gets excreted.
Dr. N.Sivaranjani
Gall stones
Supersaturation of cholesterol in bile
Due to high conc. of cholesterol to PL & Bile Salts
Cholesterol crystallise out
Gall stones
Small GS – no complication
- pass easily from CBD into intestine
Large GS – block opening of GB or CBD
- inhibits secretion of bile
- impaired dig & abs of fats
- bilirubin accumulate
- jaundice
Treatment
- Chenodeoxycholic acid – dissolve Gall Stones
- Removal of inflamed GB / stonesDr. N.Sivaranjani
Dr. N.Sivaranjani
Dr. N.Sivaranjani
Steps of lipid digestion and absorption
Step Location Enzymes
1. Minor digestion
(TAGs  DAGs + FFA)
Mouth and stomach lingual/ gastric lipase
2. Emulsification Duodenum
Bile salts, PL,
Peristalsis
3. Major digestion
TAG  MAG + 2FFA (PL)
CE  chol. + ester (CE)
PL  FA + lysoPL (PLA)
lumen of the small
intestines
Pancreatic lipase
(+colipase)
Cholesterol esterase
Phospholipase A2
4. Formation of mixed
micelles and passive
absorption
lumen of the small
intestines
Bile salts , 2MAG,
PL, chE
5. Re synthesis of lipids
Intestinal epithelial
cell
6. Assembly and export
of chylomicrons
from Intestinal cells
to the Lymphatics
Apolipoproteins and
TAG, chE, PL
Dr. N.Sivaranjani
Lipases Site of action Preferred
substrate
Products
Lingual lipase
Gastric lipase
Mouth
Stomach
TAGs with SCFA
/ MCFA
FFA + DAG
Pancreatic lipase
+ colipase
Small intestine TAGs with LCFA FFA + 2MAG
Intestinal lipase
with bile acids
Small intestine TAGs with
MCFA
3 FFA+ glycerol
Phospholipase
A2 + bile acids
Small intestine PLs with PUFA
at 2nd C
LysoPL + FFA
Important lipases for digestion of lipids
Dr. N.Sivaranjani
Dr. N.Sivaranjani

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Dig and abs of lipids

  • 1. Dr . N. Sivaranjani Asst. Prof Dr. N.Sivaranjani
  • 2. • Major dietary lipids are Triacyl glycerol -90%, Cholesterol Cholesteryl esters & Phospholipids  Indian diet contains about 20-30 g of lipids per day. Western diet – 2 or 3times more than this quantity Dr. N.Sivaranjani
  • 3. • Animal foods – Diary products like Milk, Butter, Ghee, Cheese, Meat , Fish and Eggs • Plant foods – Vegetable cooking oil – Ground nut oil, Sunflower , Palm ,Rice bran ,Coconut , Cotton seed oil. • Vegetable fat are of better quality compared to animal fats – high PUFA content. • Although rich in UFA , chance of deterioration are low because of presence of Antioxidants in them. Dr. N.Sivaranjani
  • 4. Ingestion of fatty food Enterogastrone (CCK & Secretin) from duodenum • Gastric motility & retards discharge of food bolus This Delays the rate of emptying of stomach • Fatty food have the ability to satisfy hunger. Alcohol intoxication can be avoided if consumed after ingestion of fatty food. (eg- Milk, Cream) _ + Dr. N.Sivaranjani
  • 5. • Lingual lipase – • Originates from glands at the back of the tongue • Acts of TAG containing fatty acids of short- or medium-chain length • SCFA are present in milk, butter and ghee. • MCFA – mother’s milk and coconut oil. • Optimum pH of 2.5-5 - Continues to be active in the stomach. Dr. N.Sivaranjani
  • 6. Gastric lipase / Acid stable lipase (pH-5.4) • secreted by chief cells, the secretion is stimulated by Gastrin. • Requires presence of Ca2+ • Up to 30% digestion of TAG occurs in stomach • Acts only on SCFA- milk, butter, ghee • Clinical importance :- Lipid digestion in neonates • Milk fat is the primary source of calories in neonates. Dr. N.Sivaranjani
  • 7. Human milk contains specific Lipase which is activated by bile salts in duodenum • Bile salt activated lipase – completely hydrolyses TAG of milk fat. • Premature infants – secretary function of pancreas is not fully established at birth. So depends only on these lipases. In pancreatic insufficiency – SCFA and MCFA are therapeutically used in malabsorption syndromes. Dr. N.Sivaranjani
  • 8. • phenomenon of dispersion of lipids into smaller droplets (200-5000nm) due to reduction in the surface tension Importance : • Pre- requisite / essential for digestion of lipids • Increases the surface area of the hydrophobic lipid droplets • Digestive enzymes can act effectively Dr. N.Sivaranjani
  • 10.  Emulsification is favored by  Bile salts – detergent action  Phospholipids – Surfactant action  Peristalsis - mechanical mixing Dr. N.Sivaranjani
  • 11. • Synthesized from cholesterol in the liver as bile acids. • At physiological pH, the bile acids are mostly present as anions. • Na2+ and K+ salts of Glyco-cholate, Glyco- Chenodeoxycholate, Tauro-cholate, Tauro- Chenodeoxycholate. • They are secreted with bile, into the duodenum. Dr. N.Sivaranjani
  • 12. • Most effective biological emulsifying agent • Helps in digestion and absorption of lipids • stabilize the smaller particles by preventing them from coalescing. Emulsification Micelle formation Dr. N.Sivaranjani
  • 14. • CCK – • sec. of panc. E GB to release Bile into the duodenum Gastric motility • Secretin – • sec. of HCO3 to provide appropriate pH for pancreatic enzymes + + _ + Dr. N.Sivaranjani
  • 15. • Pancreatic lipase – TAG • Cholesterol esterase - Cholesteryl esters • Phospholipase A2 - Phospholipids Dr. N.Sivaranjani
  • 16. • Pancreatic lipase • Alkaline pH (pH-7.7) is favorable for the action of pancreatic enzymes • removes the fatty acids of TAG, at carbons 1 & 3 Importance : • Cystic fibrosis - Pancreatic insufficiency leads to Significant Malabsorption of fat Dr. N.Sivaranjani
  • 18. The major end products of the digestion of TAG : 2-MAG (78%), 1-MAG (6%), Glycerol and FFA (14%). Dr. N.Sivaranjani
  • 19. Colipase • secreted by the pancreas as a zymogen • activated in the intestine by Trypsin • binds with the lipase at a ratio of 1:1 • Colipase binds at the lipid-aqueous interface and helps to anchor and stabilize lipase to its substrate TAG. • Enterostatin – acts as satiety signal for lipids. Procolipase Colipase 5 a.a Enterostatin Trypsin Dr. N.Sivaranjani
  • 20. Activity of the enzyme is increased in the presence of bile salts Pancreatic Cholesterol ester hydrolase or Cholesterol esterase Dr. N.Sivaranjani
  • 21. R2-C-O-CH CH2-O-P-N-base CH2-O-C-R1 O =O = HO-CH CH2-O-P-N-base CH2-O-C-R1 O = Glycerophospholipid Lysophospholipid Fatty acid H2O R2-COOH Phospholipase-A2 requires bile salts for optimum activity Enzyme is secreted as Zymogen form and activated by Trypsin Dr. N.Sivaranjani
  • 23. • C2 FA-is frequently Arachidonic acid in cell membrane – synthesis of Eicosinoids • Lysolecithin - is a detergent and hemolytic agent. • The Phospholipase-A2 enzyme is present in the venom of viper snakes. • In viper poisoning -hemolysis and consequent renal failure is seen. Dr. N.Sivaranjani
  • 24. R2-C-O-CH CH2-O-P-O-C-C-N-CH3 CH2-O-C-R1O = Glycerophospholipid Site of action of phospholipases O = O = O CH3 CH3H2H2 Phospholipase-A1 Phospholipase-A2 Phospholipase-D Phospholipase-C + Dr. N.Sivaranjani
  • 25. • Micelles are molecular aggregate, having a disk / spherical shape containing : Interior (hydrophobic) – 2 MAG, LCFA, cholesterol & phospholipids (hydrophobic part) Exterior (hydrophilic) - bile salts and hydrophilic part of cholesterol and PL. • SCFA & MCFA do not require the assistance of mixed micelles for absorption by the intestinal mucosa. Dr. N.Sivaranjani
  • 26. Bile salts are reabsorbed in lower part of SI and return to the liver by portal vein for resecretion into bile – Enterohepatic circulation Dr. N.Sivaranjani
  • 27. Mixed micelles serve as the major vehicles for the Absorption of lipids from the intestinal lumen to the intestinal cells Essential for the absorption of fat-soluble vitamins such as vitamin A, D and K. Dr. N.Sivaranjani
  • 28. • Digestion – Emulsification by bile salts, pancreatic enzymes • Absorption – by micelle formation with bile salts • Post-absorption – re-esterification inside Intestinal cells • Transport – chylomicrons Transport Dr. N.Sivaranjani
  • 29. Long chain Fatty acids 2-MAG Cholesterol Short chain Fatty acids & glycerol Portal circulation Lymphatic system Blood Peripheral tissues Thiokinase Carried by Albumin Re-esterification Inside the Intestinal mucosal Cell Dr. N.Sivaranjani
  • 30. Interior (hydrophobic) – 2 MAG, LCFA, cholesterol & Phospholipids Exterior (hydrophilic) - bile salts and hydrophilic part of cholesterol and PL Chylomicrons composed of: Triacylglycerols (85-90%) Cholesterol & ChE (5%) Phospholipids (7%) Apolipoprotein-B48 (1-2%) ApoB48 Dr. N.Sivaranjani
  • 31. • Lipids that are resynthesized in the intestinal cells are hydrophobic in nature, so surrounded by Apolipoproteins (apoA and B-48) and phospholipids at the exterior to form Chylomicrons. • This formation stabilizes the droplets and increases their solubility. Dr. N.Sivaranjani
  • 32. The chyle (milky fluid) from the intestinal mucosal cells loaded with chylomicrons are transported through the lacteals into the thoracic duct and then emptied into lymph circulation. Postprandial Lipemia - The serum may appear milky after a high fat meal due to the presence of chylomicrons in circulation. Normally the lipemia clears within a few hours by the uptake of chylomicrons by tissues by LPL (lipoprotein lipase enzyme) . Dr. N.Sivaranjani
  • 34. • Fate of the Chylomicrons: • Chylomicrons are the transport form of dietary triglycerides from intestines • Adipose tissue - storage • Muscle and Heart - for their energy needs. Dr. N.Sivaranjani
  • 35. • Fate of free fatty acids – • Carried by Albumin • Taken by Muscle or Adipocytes, • Oxidized to produce energy • Fate of glycerol – • Taken by liver to produce glycerol 3-phosphate • Which enters Gluconeogenesis / Glycolysis or used for TAG / PL synthesis in liver. Dr. N.Sivaranjani
  • 36. Abnormalities in lipid digestion & absorption Dr. N.Sivaranjani
  • 37. Steatorrhoea – Greek word, "stear", means fat large amount of fat or FA excreted in feces >6g day. Most common cause : Defective digestion - Pancreatic enzyme deficiency – pancreatitis cystic fibrosis Defective absorption – Celiac disease, Surgical removal of intestine, Bile salt deficiency – liver disease obstruction in bile duct due to gall stones or Ca head of pancreas. Defective chylomicron synthesis – congenital abetalipoproteinemia – defect in ApoLP synthesis.Dr. N.Sivaranjani
  • 38. In pancreatic deficiency: unsplit fat is present in stools. When bile is not available - Absorption is defective; split fat is present in stools; defective absorption of vitamin K leads to prolonged prothrombin time. Dr. N.Sivaranjani
  • 39. Pancreatin / Enzyme Supplements -Trypsin + Lipase Steatorrhea – Rx Dr. N.Sivaranjani
  • 40. • Chyluria - Abnormal connection b/w urinary tract & lymphatic drainage system of intestine. • Urine appears milky due to lipid droplets. • Chylothorax - Abnormal connection b/w the pleural cavity and thoracic duct - Milky pleural effusion. Dr. N.Sivaranjani
  • 41. Drugs used in Obesity • Orlistat is a powerful inhibitor of pancreatic lipase,hence prevents fat digestion and absorption. • Olestra is a synthetic lipid, produced by esterification of natural fatty acids with sucrose (instead of glycerol). Olestra tastes like a natural lipid. However, it cannot be hydrolysed and therefore, gets excreted. Dr. N.Sivaranjani
  • 42. Gall stones Supersaturation of cholesterol in bile Due to high conc. of cholesterol to PL & Bile Salts Cholesterol crystallise out Gall stones Small GS – no complication - pass easily from CBD into intestine Large GS – block opening of GB or CBD - inhibits secretion of bile - impaired dig & abs of fats - bilirubin accumulate - jaundice Treatment - Chenodeoxycholic acid – dissolve Gall Stones - Removal of inflamed GB / stonesDr. N.Sivaranjani
  • 45. Steps of lipid digestion and absorption Step Location Enzymes 1. Minor digestion (TAGs  DAGs + FFA) Mouth and stomach lingual/ gastric lipase 2. Emulsification Duodenum Bile salts, PL, Peristalsis 3. Major digestion TAG  MAG + 2FFA (PL) CE  chol. + ester (CE) PL  FA + lysoPL (PLA) lumen of the small intestines Pancreatic lipase (+colipase) Cholesterol esterase Phospholipase A2 4. Formation of mixed micelles and passive absorption lumen of the small intestines Bile salts , 2MAG, PL, chE 5. Re synthesis of lipids Intestinal epithelial cell 6. Assembly and export of chylomicrons from Intestinal cells to the Lymphatics Apolipoproteins and TAG, chE, PL Dr. N.Sivaranjani
  • 46. Lipases Site of action Preferred substrate Products Lingual lipase Gastric lipase Mouth Stomach TAGs with SCFA / MCFA FFA + DAG Pancreatic lipase + colipase Small intestine TAGs with LCFA FFA + 2MAG Intestinal lipase with bile acids Small intestine TAGs with MCFA 3 FFA+ glycerol Phospholipase A2 + bile acids Small intestine PLs with PUFA at 2nd C LysoPL + FFA Important lipases for digestion of lipids Dr. N.Sivaranjani