ANTIOXIDANT AND FREE RADICALS Flashcards
what is uv radiation?
high energy form of light present in sunlight
what can uv light do to molecules and the skin?
enough energy to break chemical bonds in molecules in the skin and DNA
what can uv radiation cause?
sunburn skin cancer photoaging
what are the 3 stages of uv radiation
initiation, propagation, termination
what is a free radical?
a very unstable atom or molecule with one or more unpaired electrons
Example of an anti-oxidant / free radical scavengers
Vitamin C (in food and cosmetic product)
What is an anti-oxidant?
Molecule that will get oxidised instead of an other molecule.
As it get oxidised, an anti-oxidant is a reducing agent
Which molecule is more volatile?
The one on the left as it’s smaller so will evaporate more easily
What can be done to prevent oxidation of food?
Use anti-oxidants (e.g: Vitamin C)
Pack in Nitrogen instead of air that contain oxygen
Vaccum pack to remove the air and therefore the oxygen
Cool is down to reduce the rate of reaction (Oxidation of food is a chemical reaction)
What does it mean when food is rancid?
Oxidation of food that give an unpleasant smell and taste
Name this step
Initiation
Name this step
propagation
Name this step
Termination
What is a free Radical Scavengers?
molecules like anti-oxidant that react with free radicals to form stable molecules and prevent chain reactions from occurring.
