Experiment 3. Qualitative reactions to vitamin D (calciferol) with aniline.

Laboratory work 6. Vitamins

Vitamins are organic compounds required in the diet in small amounts. They ensure the normal development of human and animal, and an adequate rate of biochemical and physiological processes.

Avitaminosis (vitamin deficiency) is a disease that occurs in the absence of food vitamins or in total violation of assimilation of any vitamin. Hypovitaminosis is insufficient intake of vitamins with food or their incomplete assimilation. Hypervitaminosis is pathological state associated with large quantities of vitamins in the organism. The causes of vitamin deficiency in humans and animals are usually divided into exogenous and endogenous. An exogenous factoris insufficient intake of vitamins or their complete absence in the diet. Endogenous factors are increased requirement for vitamins in certain physiological and pathological conditions or violation of the process of absorption of vitamins.

The classification of vitamins is based on the solubility of the vitamins: fat soluble vitamins and water soluble vitamins.

Experiment 1. Qualitative reactions to vitamin A (retinol) with sulfuric acid (Drummond’s reaction). Dissolve 1 drop of fish liver oil (or vitamin A solution) in 4 drops of chloroform and add 2 drops of concentrated sulfuric acid. The reactions is based on the dehydrating influence of sulfuric acid on vitamin A.

Vitamin A (retinol)

Experiment 2. Qualitative reactions to vitamin E (tocopherol) with concentrated nitric acid. Add 0,5 ml of concentrated nitric acid to 6 drops of 0,1% alcochol tocopherol solution in a dry test tube and shake. You will get a gradually layered emulsion the upper layer of which is red. The coloring is caused by tocopherol oxidation.

a-tocopherol a-tocohinon (toco-red)

Experiment 3. Qualitative reactions to vitamin D (calciferol) with aniline.

Pour 0.5 ml of fish liver oil and 0.5 ml of aniline and concentrated hydrochloric acid mixture into a dry test tube (15:1), mix properly, heat carefully and boil for a minute. Leave the test tube at the room temperature.

Vitamin D (calciferol)

Дата добавления: 2015-10-26