LIPIDS
Lipids
Simple compound derived
Fats and oils wax Phospholipid glycolipid lipoprotein fatty acid cholesterol sterols
lecithin cerebrosides Saturated
Simple
unsaturated
Mixed plasmalogen gangliosides
mono
sphingomyelin
poly
Eicosanoids
Def:- Lipids are a group of heterogeneous organic hydrophobic (water insoluble) compounds that
are soluble in nonpolar solvents.
• Heterogeneous group of water-insoluble (hydrophobic) organic molecules
• Can be extracted from tissues by nonpolar solvents
• Body lipids are generally found compartmentalized
– membrane-associated lipids
– droplets of triacylglycerol in adipocytes
– These molecules are highly water-insoluble and must be transported in the
circulation in association with protein as in lipoprotein particles, or on albumin.
• Lipids either contain Fatty Acids or their derivatives
• Fatty Acids – Organic Acids
• Consists of a hydrophobic hydrocarbon chain with a terminal carboxyl group
• At physiologic pH, the terminal carboxyl group (–COOH) ionizes, becoming –COO -.
Importance of Lipids
● Major stored form of energy: Their oxidation provides energy (more energy / mole
than carbohydrates.
● Enzyme cofactors: Fat-soluble vitamins have regulatory or coenzyme functions
, LIPIDS
● In bio membranes: Provide the hydrophobic barrier that permits partitioning of the aqueous
contents of cells and subcellular structures
● Electron carriers: (Coenzyme Q) the lipid-soluble electron carrier
● Emulsifying agents
● Hormones/Signalling molecules
SIMPLE COMPOUND DERIVED
FATS PHOSPHOLIPIDS FATTY ACIDS
● Esters of fatty acids Present in large amounts in nerve By the hydrolysis of fats
and glycerol. tissue, brain , liver, kidney,
● Best reserve of pancreas and heart.
food material in Saturated Fatty acids- no
the human body double bonds
● In natural fats –
straight chain
derivatives with Unsaturated Fatty acids-
even number of C one or more double bonds.
atoms
(Cis more common than
trans)
1) MONO
2) POLY
3) EICOSANOIDS
WAXES Biological functions of MONOUNSATURATED FATTY
phospholipids: ACIDS
Esters of fatty acids and
higher alcohols other than ● Increase the rate of fatty -polyunsaturated fatty acids
glycerol acid oxidation
-monounsaturated fatty acids
● Help blood clotting
● Act as prosthetic group to ● Olive oil
certain enzymes
● Peanut oil
● Form structures of
membranes, matrix of cell ● Canola oil
wall, myelin sheath,
microsomes and (good for you)
mitochondria POLYUNSATURATED FATTY
ACIDS
EICOSANOIDS –
(prostaglandin,
thromboxanes, leukotriens,
prostacyclins)
Fatty acids
Lipids
Simple compound derived
Fats and oils wax Phospholipid glycolipid lipoprotein fatty acid cholesterol sterols
lecithin cerebrosides Saturated
Simple
unsaturated
Mixed plasmalogen gangliosides
mono
sphingomyelin
poly
Eicosanoids
Def:- Lipids are a group of heterogeneous organic hydrophobic (water insoluble) compounds that
are soluble in nonpolar solvents.
• Heterogeneous group of water-insoluble (hydrophobic) organic molecules
• Can be extracted from tissues by nonpolar solvents
• Body lipids are generally found compartmentalized
– membrane-associated lipids
– droplets of triacylglycerol in adipocytes
– These molecules are highly water-insoluble and must be transported in the
circulation in association with protein as in lipoprotein particles, or on albumin.
• Lipids either contain Fatty Acids or their derivatives
• Fatty Acids – Organic Acids
• Consists of a hydrophobic hydrocarbon chain with a terminal carboxyl group
• At physiologic pH, the terminal carboxyl group (–COOH) ionizes, becoming –COO -.
Importance of Lipids
● Major stored form of energy: Their oxidation provides energy (more energy / mole
than carbohydrates.
● Enzyme cofactors: Fat-soluble vitamins have regulatory or coenzyme functions
, LIPIDS
● In bio membranes: Provide the hydrophobic barrier that permits partitioning of the aqueous
contents of cells and subcellular structures
● Electron carriers: (Coenzyme Q) the lipid-soluble electron carrier
● Emulsifying agents
● Hormones/Signalling molecules
SIMPLE COMPOUND DERIVED
FATS PHOSPHOLIPIDS FATTY ACIDS
● Esters of fatty acids Present in large amounts in nerve By the hydrolysis of fats
and glycerol. tissue, brain , liver, kidney,
● Best reserve of pancreas and heart.
food material in Saturated Fatty acids- no
the human body double bonds
● In natural fats –
straight chain
derivatives with Unsaturated Fatty acids-
even number of C one or more double bonds.
atoms
(Cis more common than
trans)
1) MONO
2) POLY
3) EICOSANOIDS
WAXES Biological functions of MONOUNSATURATED FATTY
phospholipids: ACIDS
Esters of fatty acids and
higher alcohols other than ● Increase the rate of fatty -polyunsaturated fatty acids
glycerol acid oxidation
-monounsaturated fatty acids
● Help blood clotting
● Act as prosthetic group to ● Olive oil
certain enzymes
● Peanut oil
● Form structures of
membranes, matrix of cell ● Canola oil
wall, myelin sheath,
microsomes and (good for you)
mitochondria POLYUNSATURATED FATTY
ACIDS
EICOSANOIDS –
(prostaglandin,
thromboxanes, leukotriens,
prostacyclins)
Fatty acids
