Riboflavin (B2) Flashcards
1
Q
How is riboflavin absorbed?
A
HCl in the stomach splits riboflavin from food components
Free riboflavin is absorbed by active or passive diffusion depending on concentrations. Between 60-65% absorbed
2
Q
How is riboflavin transported through the body?
A
By riboflavin carriers in the blood
3
Q
What is the coenzyme form of riboflavin?
A
FMN and FAD
4
Q
Where is riboflavins stored?
A
Small amounts in the liver, kidneys, heart
5
Q
How is it excreted?
A
In urine, causes it to become bright yellow with supplements
6
Q
What are the functions of riboflavin?
A
- The formation of niacin from tryptophan requires FAD
- Formation of vitamin B6 coenzyme requires FMN
- Synthesis of glutathione requires a FAD containing enzyme (glutathione reductase)
- FMN has a key role in energy metabolism: shuffles hydrogen atoms into the ETC
- Required for beta-oxidation
7
Q
What occurs with riboflavin deficiency
A
- Affects mouth, skin , red blood cells
- Glossitis
- Scaley skin, anemia, fatigue
Increased risk of deficiency with chronic alcoholism, oral contraceptives, stress, age
8
Q
What foods are good sources of Riboflavin?
A
- milk (dairy products)
- beef liver
- meat
- eggs
