1. Fat Soluble Vitamins Water Soluble Vitamins

2. Characteristics of Vitamins
Vitamins are micronutrients
Very small amounts are needed by the body (>1 gm)
Very small amounts are contained in foods.
Vitamins are essential.
The roles they play in the body are very important.
Most vitamins are obtained from the foods we eat.
Some are made by bacteria in the intestine
There is no perfect food that contains all the vitamins in the right amount.
Vitamins are non-energy producing
They do not contain kcalories.
Vitamins are classified according to how soluble they are in fat or water.

3. Fat Soluble Vitamins vs. Water Soluble Vitamins3

4. Fat-Soluble Vitamins

5. Fat-Soluble Vitamins Found in fats and oils
Require bile for absorption
Enter the lymph, then the blood
Held and stored in fatty tissues
Needed in small amounts
May reach toxic levels
Not readily excreted

6. Vitamin A 3 forms in the body Retinol Retinal Retinoic acid
collectively known as Retinoids
precursor: beta-carotene
derived from plant foods
can split and form retinol in intestine and liver
Beta-carotene
Dark leafy green vegetables
Deep orange veggies
Deep orange fruits

7. Vitamin A function Vision Maintain epithelial tissue and skin
Support reproduction and growth
Immune system
Bone development

8. Vitamin A Deficiency Infectious disease Keratinization Night blindness
Pneumonia, measles, diarrhea
Keratinization
Dry, rough, scaly skin
Night blindness

9. Vitamin D body can make vit D production occurs in liver and kidney
from sunlight
precursor made from cholesterol
production occurs in liver and kidney
diseases can affect activation
sources
fortified food: milk, margarine, cereals, beef, eggs
sun
storage from the summer does not last the winter

10. Vitamin D Production

11. function Vitamin D part of the bone-making/maintenance team
maintains blood concentrations of Ca & P
Mineralization of bones
raises blood calcium and phosphorus by increasing absorption from digestive tract
withdrawing calcium from bones
stimulating retention by kidneys
deficiencies
ultimately creates a calcium deficiency
osteomalacia or rickets

12. Vitamin E antioxidant defender against free radicals
polyunsaturated fatty acids
may reduce the risk of heart disease
widespread in food
easily destroyed by heat processing
deficiencies
rare
erythrocyte hemolysis
Maintenance of membranes - prevents oxidation of unsaturated fatty acids contained in the phospholipids (includes membranes of mitochondria and ER)
Reduced LDL oxidation; decreased plaque formation
Reduction in cataract formation
Reduced oxidation in diabetics
An antioxidant is a molecule that inhibits the oxidation of other molecules.

13. Vitamin K Aids in blood clotting and Bone mineralization
Deficiency causes hemorrhagic disease
Sources
Made by bacteria in GI tract
Absorbed and stored in liver

14. Water-soluble vitamins
B complex , c

15. Water soluble vitamins
The B-complex vitamins are often associated with giving a person more energy. This is due to the fact that these vitamins each play different roles with energy metabolism in the body. When they are present in the body, they allow energy to be used more readily by the body.
Since these vitamins are water soluble, they are not stored in the body like fat soluble vitamins. They dissolve in water and are excreted from the body in urine. Therefore, it is important to consume foods rich in these vitamins each day in order to fulfill the body’s need.

16. B Complex Vitamins Co-enzymes (activate enzymes)
Found in the same foods
Single deficiency rare
Act together in metabolism
Metabolic pathways used by protein, carbohydrate, and fat

17. B Complex Vitamins Thiamin (B1) Riboflavin (B2) Niacin (B3)
Pantothenic Acid
Biotin
Pyridoxine (B6)
Folate
Vitamin B-12

18. B Complex Primary Functions
Energy metabolism
Thiamin (B-1), Riboflavin (B-2), Niacin (B-3), Pyridoxine (B-6), Biotin, Pantothenic Acid
Red blood cell synthesis
Folate, B12
Homocysteine metabolism
Folate, B12, B6

19. Vitamin C Synthesized by most animals (not by humans)
Decrease absorption with high intakes
Excess excreted

20. Food Sources of Vitamin C
Citrus fruit
Potato
Green pepper
Cauliflower
Broccoli
Strawberry
Romaine lettuce
Spinach

21. Functions of Vitamin C Reducing agent (antioxidant)
Iron absorption (enhances)
Synthesis of collagen
Immune functions
Does not prevent colds, but may reduce duration of symptoms by a day
Wound healing
Easily lost through cooking
Sensitive to heat
Sensitive to iron, copper, oxygen

22. Vitamin C Deficiency: History of Scurvy
Vitamin C (ascorbic acid) deficiency leads to scurvy, a disease characterized by weakness, small hemorrhages throughout the body that cause gums and skin to bleed, and loosening of the teeth Sailors that were out at sea for months on end would often develop scurvy unless the captain had the foresight to pack limes and other citrus fruits.
In the U.S., deficiency is seen mostly in alcoholic persons with poor diets and older persons who eat poorly (no fresh fruits and vegetables)

23. Follicular Hemorrhages
Scurvy
Follicular Hemorrhages
Scorbutic Rosary

24. Vitamin C Excess Hemochromatosis Oxalate kidney stones
Vitamin C enhances iron absorption
Oxalate kidney stones
Erodes tooth enamel

25. Determination of Vitamin C (Ascorbic Acid) Concentration
by a Redox Titration with Potassium Iodate (KIO3)

26. Ascorbic Acid (Vitamin C) & Redox Titration With Potassium Iodate
is sometimes called an anti-oxidant. (i.e., a reducing agent!) by pharmacists and food nutritionists.
Iodometric titrations. In "iodometric" titrations, the analyte is first reduced with an excess of I-, producing I2 (actually, I3-) which turns blue in the presence of starch.
A suitable method for the determination of vitamin C (C6H8O6) quantities is a titration with potassium iodate (KIO3).
Iodine rapidly oxidizes ascorbic acid, C6H8O6, to produce dehydro-ascorbic acid
C6H6O6: C6H8O6 + I C6H6O6 + 2I. + 2H+

27. Objective: To determine vitamin C (C6H8O6) by potassium iodate titration and to master
Potassium iodate is used as a titrant and it is added to an ascorbic acid solution that contains strong acid and potassium iodide (KI).
Potassium iodate reacts with potassium iodide, liberating molecular iodine (I2):
As long as the solution contains ascorbic acid, the iodine produced in (1) is used up in a rapid reaction with ascorbic acid, during which dehydroascorbic acid and iodide ion are formed:

28. Potassium iodide must be added in excess to keep iodine dissolved.
Once all the ascorbic acid has been consumed, any excess iodine will remain in solution. Since aqueous iodine solutions are brown in colour, iodine can act as its own indicator.
However, it is quite difficult to detect endpoints using iodine coloration alone, and it is more usual to add starch, which forms an intensely blue coloured complex with iodine but not with the iodide ion.

29. The addition of acid is necessary to provide the acidic conditions required in reaction (1) above.
The endpoint of the titration is the first permanent trace of a dark blue-black colour due to the starch-iodine complex.

30. Note: The end point is reached when the solution turns a permanent, dark blue colour, due to the complex formed between starch and iodine.
During an iodometric titration an intermediate dark blue iodine-starch complex may form momentarily, before the iodine reacts with ascorbic acid.
However, if the colour disappears upon mixing, the end point has not yet been reached.
Thus, magnetic stirrers or glass rod are employed in the titration to ensure proper mixing and to facilitate the reaction of iodine with ascorbic acid.

31. Iodometric Titrations
Molecular iodine (I2) is only slightly soluble in water but adding iodide, I-, produces the "triiodide" ion (I3-) in solution. Thus, KI is almost always added when redox reactions of
I2 are involved in quantitative analysis.
I2(s) + I-(aq) I3(aq)
Iodine iodide triiodide
Starch is used as the indicator in most iodometric titrations because iodine (i.e., I3)forms an intense blue colored "starch-iodine complex."
Redox Indicator is a chemical compound that undergoes a color change as it goes from its oxidized form to its reduced form.

32. Experiment
Principle
1. KIO3 is used as a titrant and it is added to an ascorbic acid
solution that contains a strong acid and potassium iodide (KI).
2. KIO3 reacts with KI, liberating molecular iodine (I2):
KIO3 + 5KI + 6H+ → 3I2 + 6K+ + 3H2O ……………(1)
C6H8O6 + I2 → C6H6O6 + 2I- + 2H+ …………..(2)

33. According to the above reactions, each mole of potassium iodate added corresponds to 3 moles of ascorbic acid dehydrogenated in the sample.

34. Procedure
1. Pipette 25 ml of the provided ascorbic acid solution into a 250 ml conical flask,
2. Add  4 ml of 2M HCl,
3. Add  5 ml of potassium iodide (KI) solution and 3 ml starch solution.
4. Then titrate with the standard potassium iodate (KIO3) solution until the solution turns intense blue. Write down the standard potassium iodate (KIO3) solution volume.
5. Pipette 25 ml of an unknown ascorbic acid sample, a kind of juice, into a 250 ml conical flask, then follow the same procedure of steps 1-4 and write down the volume of the standard KIO3 solution determine the concentration (mol/ml) of ascorbic acid in the selected sample.

35. procedure

37. Take Care Of Your Vitamins Health