Module3_Lipids

• Lipids are biomolecules that are soluble in organic solvent like; ether, hexane, and chloroform, and insoluble in water. This if bcs of "like dissolves like".
• The main function of lipid is to store energy.
• There are two types of lipids; simple lipids (fats & oils), complex lipids (phospholipids).
• Simple Lipids - Fats and Oils
• Lipids contain many non-polar C-C and C-H bonds which result to their insolubility with water.
• Category of Lipids:

  • Hydrolyzable - these lipids can be converted into smaller molecules through hydrolysis (aided by acid, base, enzyme).
  • Non-hydrolyzable - lipids that cannot be cleaved into smaller molecules by aqueous hydrolysis.
• Hydrolyzable Lipids

  • Waxes
  • Triacylglycerols
  • Phospholipids
• Non-hydrolyzable:

  • Steroids
  • Fat-soluble vitamins
  • Eicosanoids
• Simple Lipids - Fats, waxes, oils, made up of glycerol and three fatty acids.
• Compound/Complex Lipids - lipoproteins, glycolipids, phospholipids, there are lipids that is joined with other molecules.
• Derived/Miscellaneous Lipids - steroids, hormones, fat-soluble vitamins.
• Major roles of Lipids:

  • They serve as structural components of biological membranes.
  • They provide energy reserves, predominantly in the form of triacylglycerols or triglycerides.
  • Serves as a vitamins and hormones
• Saponifiable lipids - can be hydrolysed by base (basic hydrolysis) ; example, simple and complex lipids.
• Non-saponifiable Lipids - not hydrolysed by a base, example, derived lipids.
• Hydrolyzable lipids are derived from fatty acids.
• Fatty acids are the building blocks of simple and complex lipids, they are carboxylic acid (RCOOH) with LONG and EVEN chains of carbon and hydrogen, around 12-20 C atoms.
• Polar portion - Hydrophilic

  Non-polar portion - Hydrophobic
• Naturally occurring fatty acids have an even number of C atoms.
• Saturated fatty acids have NO double bonds in their long hydrocarbon chains.
• Unsaturated fatty acids have 1 or MORE double bonds (generally cis) in their long hydrocarbon chains
• As the double bond of fatty acid INCREASES, the melting point DECREASES.
• CIS - same side

  TRANS - different/opposite side
• Essential fatty acid - are those that cannot be produced by the body and must be consumed.
• Essential fatty acids are omega-6 and omega-3
• Omega-6 because the first double bond is located at the 6th carbon.

  Omega-3 because the first double bond is located at the 3rd carbon.