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VITAMINS AND VITAMIN-CONTAINING DRUGS



Vitamins are organic substances, not synthesized with the body, that are essential in small amounts for the maintenance of normal metabolic functions. They do not furnish energy and are utilized as building units for cellular structure. The lack of specific vitamins leads to distinctive deficiency states such as beriberi, rickets, scurvy, and xerophthalmia, or to the conditions without definitive symptoms.

The term vitamin was derived in 1911 when an amine thought to prevent beriberi was isolated from rice bran; this essential or vital amine was called a vitamin. The term has been retained even though it is technically incongruous. Not all vitamins are amines; vitamins A, C, D, Е, К, and inositol lack a nitrogen function of any type. The vitamins are diverse chemically, ranging from a simple molecule such as niacin to a complex molecule such as cyanocobalamin. Vitamins are distributed widely and are normally ingested as constituents of various food substances. Fresh fruits, leafy vegetables, whole grains, eggs, and liver are rich dietary sources of vitamins. Standardized, partially purified concentrates and isolated vitamins can be obtained for commercial purposes from a variety of animal, microbial, and plant sources; however, chemical synthesis is more feasible for many of the vitamins. Vitamins obtained from natural sources and those prepared synthetically are indistinguishable biochemically, nutrutionally, and therapeutically.

Vitamins may be used as special dietary supplements or as drugs. Vitamin supplements are technically foods for special dietary needs and are unnecessary in most cases in which there is a balanced diet. Vitamins are considered drugs if they are taken to treat a condition of vitamin deficiency or to prevent imminent development of disease. Deficiency conditions are classic therapeutic uses for vitamins, but recognition of their utility in a variety of hereditary conditions (inborn errors of metabolism) is increasing. The risk to health associated with daily ingestion of unnecessary vitamins is undoubtedly less than with over ingestion of caloric foods, but the pharmacist and other health professionals must be alert to the need for detailed diagnostic assessment if an actual



deficiency is suspected.

The United States Food and Drug Administration (FDA) requires that vitamin products be labeled to show the percentage of the United States recommended daily allowance (US RDA) for each ingredients. The actual dietary needs depend on a number of variables, including age, illness, sex, stress, and weight. The US RDA guidelines are set sufficiently high to compensate for individual variations in the normal person. Extra strength formulations are frequently employed in situations of special need, such as pregnancy. When individual vitamins are used to treat inborn errors of metabolism, the dosage regimens are not related to the US RDA estimate.

It is convenient to classify the vitamins into two groups:

a) fat soluble - - vitamins A, D, Е, К;

b) water soluble - - vitamins В, С.

Vitamins don't yield energy but act as catalysts. They cannot be manufactured in the body, and are supplied from outside.

Write down what vitamins are described.

A.This vitamin is not found in very much food. It may also be produced by the body. It has been called the sunshine vitamin. Without this vitamin bones become very weak and the kidneys cannot work properly. It’s a white crystalline material, soluble in fat solvent and stable to heat, acids and oxidation.



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B.This vitamin is pale, viscous, fat soluble. It’s essential for tissues and is needed for cell growth. It helps maintaining resistance to infection. It helps in proper vision during light. Daily requirement of it is 3500 I.U. the important sources of this vitamin are cabbage, spinach, mint. Its deficiency leads to impairment of growth and reduced resistance to infection, night blindness.

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Complete the table

Food A B C D E
         
Vitamin’s action          
         

 

 

Task II. Read and translate the text«Fats and Oils »

Fats and Oils

Lipids are the compounds that can be extracted from cells and tissues by non-polar organic solvents. They are the water insoluble components derived from plants and animals.

The classification is rather unusual, since lipids. have no characteristic chemical or structural properties. The only common thread connecting the compounds in this group is their method of isolation and similar biogenetic origins. In many respects the lipid classification is a catch-hall for many diverse and inbiological molecules.

Fats and oils contain carbon, hydrogen and oxygen and they are the most esters of long-chain carboxylic acids. Because they can be formed from excess carbohydrates in living organisms, fats and oils function is a major storehouse of energy.

Fatsare solid triglycerides, whereas oils are liquids at typical room temperature. It is common practice to all viscous organic liquids oils.

The fatty acids of which fats and oils are composed are usually non-branched molecules containing from *4 to 22 carbon atoms. Interestingly, they almost always possess an even number of carbon atoms — a act that is related to their biosynthetic origin. Both saturated and unsaturated fatty acids are commonly recovered from the hydrolysis of lipid materials.

• Triglycerides may be esters of identical or different fatty acids. Natural fats and oils are mixtures of glycerol; esters in which one or two fatty acid components usually predominate. For example, olive oils contain a high percentage of oleic acid and corn oils are composed principally of linoleic and oleic acids, are the common unsaturated oils used in food preparation. Butter contains many fatty acids, most are saturated. Solid triglycerides (fats) normally have a higher percentage of saturated fatty acid.

It's the complete hydrolysis that provides the component fatty acids plus glycerol. Saponification of fats and oils is the industrially important method of making soap. The enzyme lipase hydrolyzes during the digestive process. Unsaturation in fats and oils is usually determined by quantitative addition of iodine to the double bond. Hydrogenation of the double bonds of unsaturated oils is the industrial method for converting oils to fats. It's oxidation associated with the double bond that is of commercial and biological importance. Controlled oxidation of oils is the problem in the long-term storage of foods; for it is an important pathway of biological degradation.

Answer the questions

1. What elements do fats contain?

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2. How are fats definite?

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3. What are fats characterized by?

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4. Does fat conduct heat poorly?

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5. Where is fat of the body deposited?

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Translate into English

1. Омилення жирів та масел є важливим процесом для виробництва мила.

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2. Серед інших олій оливкова містить багато олійної кислоти.

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3. Саме ліпаза гідролізує жири в процесі травлення їжі.

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4. Жири дійсно складаються з кисню,водню, вуглецю.

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Task IIІ. Read and translate the text«TINCTURES»

TINCTURES

Tinctures are alcoholic or hydroalcoholic solutions prepared from vegetable materials or from chemical substances.

The portion of drug represented in the different chemical tinctures is not uniform but varies according to the established standards for each. Traditionally, tinctures of potent vegetable drugs essentially represent the activity of 10 g of" the drug in each 100-ml of tincture, the potency being adjusted by the following assay. Most other vegetable tinctures represent 20 g of the respective vegetable material in each 100 ml of tincture.

The general processes to be employed for manufacture of tinctures, unless otherwise directed in the individual monographs, are as follows:

Process P - - Carefully mix the ground drug or mixture of drugs with a sufficient quantity of the prescribed solvent or solvent mixture to render it evenly and distinctly damp, allow it to stand for 15 min, transfer it to a suitable percolator, and pack the drug firmly. Pour on enough of the prescribed solvent or solvent mixture to saturate the drug, cover the top of the percolator and, when the liquid is about to drip from the percolator, close the lower orifice, and allow the drug to macerate for 24 hours or for the time specified in the monograph. If no assay is directed, allow the percolation to proceed slowly, or at the specified rate, gradually adding sufficient solvent or solvent mixture to produce 1000 ml of tincture, and mix. If an assay is directed, collect only 950 ml of percolate, mix this, and assay a portion of it as directed. Dilute the reminder with such quantity of the prescribed solvent or solvent mixture to produce a tincture1: that conforms to the prescribed standard, and mix.

Process M- - Macerate the drug vith 750 ml of the prescribed solvent or solvent mixture in a container tint сип be closed, and put in a warm place.Agitate it frequently during 3 days or until the soluble matter is dissolved.Transfer the mixture to a filter, and when most of the liquid has drainedаwaу, wash the residue on the filter with a sufficient quantity of the prescribed solvent or solvent mixture, combining filtrates, to produce 1000 ml of tincture, and mix.

Tinctures require storage in light, light-resistant containers, away from direct sunlight and excessive hot.

1. Answer the questions:

1. What are tinctures?

________________________________________________________

2. What is the traditional potency of tinctures from vegetable drugs?

________________________________________________________

3. Is the portion of drug in chemical tinctures uniform?

_________________________________________________________

4. Where should be tincture stored?

________________________________________________________

 


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