lipids

• LIPIDS

  • soluble in organic solvents
  • insoluble in water
• LIPID

  • contains NON-POLAR C-C & C-H bonds
• HYDROLYZABLE LIPIDS

  • waxes
  • triacylglycerides
  • phospholipids
• HYDROLYSIS OF LIPIDS

  • involve enzyme: lipase
  • H2O + enzyme
  • converted into smaller molecules
• NONHYDROLYZABLE LIPIDS

  • cannot be broken down into smaller molecules by aqueous hydrolysis
• HYDROLYZABLE LIPIDS

  • CAN be broken down into smaller molecules by HYDROLYSIS
• NONHYDROLYZABLE LIPIDS

  • steroids
  • fat-soluble vitamins
  • eicosanoids
• LIPIDS = monomer: fatty acids
• fatty acids in lipids = carboxylic acids ; long C chains ; 12-20 C atoms
• POLAR PORTION = HYDROPHILIC

  NON-POLAR PORTION = HYDROPHOBIC

  
• TRIACYLGLYCERIDES = MORE THAN 10+ C
• naturally occurring fatty acids = EVEN number of C atoms
• SATURATED FATTY ACIDS = NO DOUBLE BONDS
• UNSATURATED FATTY ACID = 1 or more DOUBLE bonds (cis)
• increase number of double bonds = melting point decreases
• STEARIC ACID = SATURATED FATTY ACID
• OLEIC ACID = UNSATURATED FATTY ACID
• STEARIC ACID = SOLID AT ROOM TEMP
• OLEIC ACID = LIQUID AT ROOM TEMP
• STEARIC ACID & OLEIC ACID = 18 C atoms
• OLIVE OIL = UNSATURATED
• LAURIC ACID = DODECANOIC ACID

  • 12 C atoms
• MYRISTIC ACID = TETRADECANOIC ACID

  • 14 C atoms
• PALMITIC ACID = HEXADECANOIC ACID

  • 16 C atoms
• STEARIC ACID = OCTANOIC ACID

  • 18 C atoms
• ESSENTIAL FATTY ACIDS = LINOLEIC & LINOLENIC ACIDS
• LINOLEIC ACID = OMEGA-6 ACID

  • 2 double bonds
• LINOLENIC ACID = OMEGA-3 ACID

  • 3 double bonds
• OLEIC ACID = 1 double bond

  • double bond at C9
  • 18 C
• LINOLEIC = OMEGA 6

  • 2 double bond
  • double bond at C9 & C12
• LINOLENIC = OMEGA 3

  • 3 double bonds
  • double bond at C9, C12, C15
  • polyunsaturated
• WAXES = ESTERS
• WAXES = forms fatty acids + alcohol
• formation of WAXES

  
• WAXES = 16-30 C atoms
• SPERMATI WAX = heads of sperm whales

  • palmitic acid + cetyl alcohol = cetyl palmitate
• WAXES = HYDROPHOBIC

  • non-polar C chains
• WAXES = form protective coatings

  • make up beeswax
  • sheep's wool
  • bird's feathers
• palmitic acid + myricyl alcohol = myricyl palmitate ( BEESWAX )

  • hydrophobic = palmitic acid
  • hydrophilic = myricyl alcohol

  
• TRIACYLGLYCEROLS = TRIGLYCERIDES