Lycopene

Question 1

What is lycopene?

Answer 1

• Lycopene is a red carotenoid pigment that colours tomatos and many other red, orange, yellow fruits/veg
• Has potential health benefits

Question 2

Lycopene solubility?

Answer 2

Not soluble in water and low solubility in solvents

Question 3

Lycopene polarity?

Answer 3

It consists entirely of carbon and hydrogen so is a non-polar hydro-carbon

Question 4

Lycopene melting point?

Answer 4

High at 172-173 degrees

Question 5

Moleculer structure of lycopene?

Answer 5

• Is polyunsaturated and in its natural form all the double bonds are in trans rather then cis form
• Has alternating double bonds
• In lycopene there are 22 carbon atoms in the conjugated
  system. This means that the bonding electrons for each of these carbons become “delocalised”. They are shared between all 22 of the carbon
  atoms which participate in this system and become a part of a molecular orbital (these factors make it different to most polyunsaturated acids)

Question 6

Significance of conjugation in lycopene?

Answer 6

• The conjugation makes the molecule linear and infexible with no free rotation
• Only van de waals forces
• Makes it quite insoluble
• Can absorb some wave lengths of light but not red which makes it a bright colour red
• Is stable
• Many possible isomers

Question 7

Lycopenes in health

Answer 7

• the molecule is an important intermediate in the
  biosynthesis of many other carotenoids including -
  carotene. It is often referred to as a phytochemical
  (simply meaning plant molecule) involved both in
  photosynthesis as well as photoprotection through its
  ability to minimise oxidative damage to the structure of
  the chlorophyll molecule
• powerful antioxidant and consumption is
  associated with reduced cancer risks and enhanced
  well-being. It is also amongst the phytochemicals
  thought to reduce the risks of cancers of the
  oesophagus, lungs, prostate and stomach

Question 8

Lycopene in food?

Answer 8

Low levels are found in
animal foods including chicken liver.
- Green vegetables can be significant sources.
Asparagus, parsley and basil are examples where the
red colour of lycopene is masked by the chlorophyll
present.

Question 9

Lycopene as a food additive?

Answer 9

Lycopene is sometimes used to colour food and it is an

approved food additive in some but not all countries

Question 10

Health benefits of antioxidants?

Answer 10

• Antioxidants are responsible for keeping high-energy reactions from damaging essential DNA and proteins.
• Lycopene
  and other carotenoids operate by a singlet quenching mechanism, which is a well-recognised mechanism of
  antioxidant action. They react with singlet oxygen, 1O2,
  returning it to the relatively unreactive triplet state

Lycopene may be the most powerful carotenoid
quencher of singlet oxygen [6]. Test tube studies
indicate that it is 100 times more efficient at quenching
singlet oxygen than vitamin E