China GMP Manufacturer Vitamin C

• Varieties: Vitamins
• Component: Vitamins
• Type: The First Class
• Pharmacodynamic Influential Factors: Repeated Medication
• Storage Method: Moisture Proof
• Transport Package: Carton
• Specification: 25kg
• Origin: China

Product Description

 Vitamin C

Vitamin C occurs in two forms, namely L-ascorbic acid (reduced form) and dehydro-L-ascorbic acid (oxidized form). Although in nature the vitamin is primarily present as ascorbic acid, both forms are biologically active. The L-isomer of ascorbic acid is biologically active; the D-isomer is not. In nature, the reduced form of ascorbic acid may reversibly oxidize to the dehydroxidized form, the dehydroascorbic acid is irreversibly oxidized to the inactive diketogulonic acid. Since this change takes place readily, vitamin C is very susceptible to destruction through oxidation, which is accelerated by heat and light. Reversible oxidation-reduction of ascorbic acid with dehydroascorbic acid is the most important chemical property of vitamin C and the basis for its known physiological activities and stabilities (Moser and Bendich, 1991). Vitamin C is the least stable and, therefore, most easily destroyed of all the vitamins. Vitamin C is a white to yellow-tinged crystalline powder. It crystallizes out of water as square or oblong crystals (Illus. 6-1), slightly soluble in acetone and lower alcohols. A 0.5% solution of ascorbic acid in water is strongly acid with a pH of 3. The vitamin is more stable in an acid than an alkaline medium. A number of chemical substances, such as air pollutants, industrial toxins, heavy metals and tobacco smoke, as well as several pharmacologically active compounds, among them some antidepressants and diuretics, are antagonistic to vitamin C and can lead to increased requirements for the vitamin.