Lipids, lipid structure, fatty acids, TAG, + phospholipids

T/F Are lipids generally soluble in H2O?

False

What are the 6 thongs that lipids do?

1. important source of energy

2. a part of the cell membrane

3. supply essential fatty acids

4. allows for the absorption of fat soluble vitamins

5. increase palatability of food/feed

6. condition the feed

What is the importance of the lipids supplying essential fatty acids?

used for synthesis of hormones

What happens if there is too much fat & who specifically doesn’t like added fat?

too much fat decreases palatability and ruminants especially dislike added fat

What does conditioning the feed mean?

decrease dust, decrease fines + decrease sorting

What are the fat soluble vitamins?

ADEK

What are fatty acids made up of?

straight chains of hydrocarbons

What are the 2 types of fatty acids?

saturated fatty acids (SFA) + unsaturated fatty acids (UFA)

Describe saturated fatty acids (SFA).

no C=C bonds

contain all of the hydrogens they can contain

Describe the unsaturated fatty acids (UFA).

contain 1 or more C=C bonds

missing 2 hydrogens per double bonds

Which type of fatty acid (SFA or UVA) gives the most energy and why?

SFA contains the maximum energy value because it hasn’t lost hydrogens due to double bonds.

UFA contains less energy because they lose 2 hydrogen per double bond

What are the 2 types of UFA?

1. monounsaturated fatty acids (MUFA)

2. polyunsaturated fatty acids (PUFA)

What is the difference between MUFA & PUFA?

MUFA contains 1 C=C bond & only missing 2 hydrogens

PUFA contains >1 C=C bonds & missing 2 hydrogens per C=C bond

What are the 2 “functional groups” on either side of the TAG structure?

carboxylic acid (-COOH) & methyl (-CH3)

example: CH3-(CH2)11-COOH

What determines the fluidity of the lipid?

the # of double bonds

Increasing the # of double bonds does what?

decreases the melting point

Are oil and fat the same at room temperature and if not what causes them to be different?

Oil is liquid at room temp due to it having many more double bonds

Fat is solid at room temperature due to it having few double bonds

What is 95% of the lipid consumed?

triacylglycerol (TAG)

What does triacylglycerol with lipase + 3H2O result in?

3 fatty acids + 1 glycerol backbone

The 3 fatty acids + 1 glycerol backbone with acyl CoA synthetase results in what?

TAG synthesis (dehydration) + 3H2O

What is the structure of phospholipids?

Sn1 position = SFA

Sn2 position = MUFA or PUFA

Sn3 position = polar head group

What is hydrophobic in the phospholipid?

The SFA @ Sn1 & the MUFA or PUFA @ Sn2

What is hydrophilic in the phospholipid (i.e. what will interact with the water)?

the polar head group