Presentation

10. 11. 2005

Libor Zouhar

L – Ascorbic acidL – Ascorbic acid

Vitamin C

L – Ascorbic acid

Chemical formulas

Summary formula:

Geometrical formulas:

C6H8O6

The effective form for treatment of colds and flu is the ascorbate form.

The bioactive form of vitamin C is only the L-form (synthetic ascorbic acid: 50 % L-form + 50 % D-form; natural sources of vitamin C contain only the L- form).

Chemical and physical properties

Molecular Weight:

Density:

176,13 g/mol

1,65 g/cm3

pH: 2,2-2,5 (50 g/l, 20 °C)

Solubility in water: 330 g/l (24 °C)

Melting point: 190-192 °C

LD50 (oral, rat) : 11900 mg/kg

Vitamin C is destroyed by oxygen, heat (above 70 °C), light, freeze and reductans.

- Hungarian Nobel Laureate in Medicine (1937)

Albert von Szent-Györgyi Nagyrapolt (1893-1986)

He was the first who isolated vitamin C (in 1926).

Deficiency of vitamin C knew people much more before as a scurvy. Scurvy killed more sailors than were lost in all sea battles.

scurvy = kurděje

Why is vitamin C „VITAMIN“ for man?

Man is one of the four mammalian species, who cannot produce own vitamin C.

Mammalians need the four enzymes to make vitamin C.

We have the first three enzymes. The fourth enzyme we lost somewhere in our evolution and so ascorbic acid became a vitamin for us.

mammalian species = savčí druhy

to obtain = získat

We have to obtain the vitamin C from our diet.

Vitamin C should be consumed every day because it cannot be stored for later use.

RDA = 60 mg vitamin C

Sources of Ascorbic acid

Ascorbic acid is widely distributed in fresh fruits

and vegetables.

Rosehips

Amount of vitamin C[mg / 100 g food]

Rosehip 2000Kiwifruit 90Broccoli 90

Orange juice (3/4 cup) 75Strawberry 50

Orange 50Lemon 40

1 potato 25Banana 9Apple 6

Plant sources

"Vitamin C should be given to the patient while the doctors found the diagnosis."

People who have high blood levels of vitamin C live 6 years

longer than those who have lower blood levels.

Vitamin C is one of the most important vitamins.

Functions of vitamin C

The main function of Vitamin C in the body is the manufacture of collagen, the main protein substance of the human body. This protein makes up the structures that hold our bodies together, such as connective tissues, cartilage or tendons.

____________________________________________________________connective tissue = pojivová tkáň

cartilage = chrupavka

tendon =šlacha

Vitamin C is essential for wound repair and healthy gums.

Vitamin C plays an important role in all immune system functions. It helps reduce cholesterol levels and high blood pressure. Vitamin C is required for synthesis of dopamine, noradrenaline and adrenaline in the nervous system. Vitamin C is also needed to synthesise carnitine, important in the transfer of energy to the cell mitochondria.

……essential = základní, nezbytný

wound = zranění

gum = dáseň

Vitamin C is also a highly effective antioxidantantioxidant =

it can absorb free oxygen radicals. Even in small amounts vitamin C can protect indispensable molecules in the body, such as proteins, lipids, carbohydrates, and nucleic acids (DNA and RNA) from damage by free radicals.

indispensable = nepostradatelný

Thank you for your attention.