560C Test 2 Flashcards
active vitamin C isomer
L isomer
Vitamin C role in collagen
3 hydroxylation reactions require Vitamin C.
Vitamin C primary role as antioxidant
- Reducing agent or electron donor and thereby has antioxidant activity or functions.
- Regenerates viatmin E and glutathione
What is the Body pool of vitamin C
2g
RDA of vitamin C
- Men 90 mg
* Women 75 mg
UI of Vitamin C
2g
Vitamin C deficiency
Scurvy symptoms - fatigue, enlarged hair follicles, red skin discoloration, ruptured blood vessels, easy bruising - joint pain - oral changes
functions of vitamin C
collagen synthesis, carnitine synthesis, tyrosine synthesis and catabolism and neurotransmitter synthesis
mineral interference with vitamin C
iron and copper
vitamin C absorption rates
• Absorption of vitamin decreases with increased intake
o 16% is absorbed at high intakes (~12g) vs 98% at low intakes (<20 mg)
Thaimin B?
B1
Riboflavin B?
B2
Niacin B?
B3
Pantothenic Acid B?
B5
Pyridoxine B?
B6
Biotin B?
B7
Folate B?
B9
Cobalamin B?
B12
thaimin Major function
• Metabolism of carbohydrates, branched chain amino acids and fatty acids – energy
o Energy transformation (coenzyme role)
o Synthesis of pentoses and NADPH: (coenzyme role)
o Membrane and nerve conduction (non coenzyme)
Riboflavin Major function
o Oxidation-reduction (redox) reactions metabolism of carbohydrates, lipids, and proteins. Glutathione reductase o Metabolism of other vitamins Conversion of B6 to
Niacin Major function
- 200 enzymes require NAD and NADP
- redox role
- NADPH, Acts as a reducing agent in many biosynthetic pathways such as fatty acid, cholesterol and steroid hormone synthesis
Pantothenic Acid Major function
- Component CoA and 4’phosphopantethenine
- Acetylates nutrients including sugars and proteins among others
- Metabolism of carbs, lipids and protein
- critical to the manufacture of red blood cells, as well as sex and stress-related
Pyridoxine Major function
- amino acid metabolism
- gene expression
- schiff base
- First step in synthesis of heme
- Niacin synthesis from tryptophan requires PLP
Biotin Major function
- help the body to convert food (carbohydrates) into fuel (glucose), which is used to produce energy.
- metabolize fats and protein.
- biotin required for cells to progress normally
Folate Major function
o One carbon metabolism o Nucleic acid metabolism DNA metabolism • Synthesis of DNA from precursors • Synthesis of methionine from homocysteine • SAM o Amino acid metabolism
Cobalamin major functions
o conversion of homocysteine into methionine,
o converts L methylmalonyl-CoA to succinyl-CoA
Thiamin stored
• Human body contains about 30mg of thiamin,
o High but small concentrations in liver, skeletal muscles, heart, kidneys and brain
o Skeletal muscles are thought to contain half of body’s thiamin
Riboflavin stored
o greatest amount found in liver, kidneys and heart
Niacin stored
• NAD or NADP trapped in cell
Pantothenic Acid stored
- Pantothenic acid is free in blood, primarily within red blood cells
- Most Pantothenic acid is used to synthesize or resynthesize CoA, found in high concentrations in the liver, adrenal gland, kidney, brain and heart
Pyridoxine B6 stored
• Muscles are major storage site, 75-80%
o 40-185 mg
Bitoin stored
- Biotin found in plasma is mostly free (~ 80%), unbound state with lesser amount bound to plasma proteins,
- Stored in small quantities in muscle, liver and brain
Folate stored
o ½ stored in liver
B12 stored
mainly in liver
• Small amounts in muscle, bone, kidneys, heart, brain and spleen
