Lipids (fats and oils)

1
Lipids (fats and oils)

• The formation of a triglyceride
• one molecule three molecules one
  molecule water
• of glycerol of fatty acids of a triglyceride
• H H
• H C OH HOOC.R1 H C
  OOC.R1
• H C OH HOOC.R2
  H C OOCR2 3H2O
• H C OH HOOC.R3
  H C OOC.R3
• H H

2
Ester link

• The reactions between the fatty acids and
  glycerol are examples of condensation reactions
  i.e. water is eliminated.
• The glyceride molecule is always the same but the
  fatty acids vary.
• The condensation reaction occurs between the
  carboxyl group (COOH) of the fatty acid and the
  hydroxyl group (OH) of the glycerol.
• H O
  H O
• H C OH HO C R H
  C O C R
  
• ester link

3
Phospholipids

• Phospholipids are important componants of the
  cell membrane.
• One of the glycerol hydroxyl groups is esterified
  by phoshoric acid (H3PO4) rather than by a fatty
  acid
• ester links ( O )

H H H C OH
HOOC.R1 H C OOC.R1 H C OH
HOOC.R2 H C
OOCR2 3H2O H C OH
HO P OH H C
OP O(H) H OH
O H OH O
4
Simplified structure

• fatty acids -
• 
  non-polar
• glycerol
  hydrophobic (repels water)

phosphate group - polar hydrophilic (attracts
water)