GLYCERIN (Glycerinum; synonym: glitserol, trioksipropan, 1,2, Z-propantriol) — triatomic alcohol, CH 2 OH — CHOH — CH 2 OH, the most important component of seed and animal fats and other lipids. Is biol, substrate for many enzymatic reactions proceeding in animal and vegetable organisms and microorganisms, napr, reactions of transformation of G. into beta and hydroxy-propanoic aldehyde, to-ruyu catalyzes a glitseroldegidrataz (KF 220.127.116.11), the reaction of transfer of phosphate from ATP to G. catalyzed by glitserolkinazy (KF 18.104.22.168), etc.
G. represents a viscous sweet, colorless liquid, [and] 20 t ° is equal 1,26, kip 290 °, t ° pl 17,9 °. It is very hygroscopic, with water and alcohol mixes up in any relations, it is not ether-soluble, chloroform, benzene.
Receive G. saponification of fats, in the course of fermentation, and also synthesize from propylene. In the industry glycerin is received by hl. obr. as by-product of soap-producing production.
At soft oxidation of G. mix of glyceraldehyde and dihydroxy acetone is formed. Both of these connections «in the form of phosphoric ethers are intermediate products fermentations (see) and glycolysis (see). Full ester G. and nitric to - you — nitroglycerine (see). G. received by nitration — strongly explosive liquid; nitroglycerine is used in medicine as vasodilating medicine. Mix of nitroglycerine with infusorial earth (dynamite) is applied - to blasting.
In G.'s organism the lipase of enzymatic disintegration of glycerides and ethers G. in fabrics is constantly formed in the course of digestion of fats in a small intestine under action. This G., as well as G. accepted with food is exposed to oxidation to carbonic acid and water with allocation of energy and is partially used for resynthesis of fats (see. Lipometabolism ).
It is used in biochemistry for extraction of enzymes from fabrics.
Use of glycerin in medicine
In pharm, practice glycerin is used as an izvlekatel, solvent (phenol, boric to - you, etc.), a basis for preparation of ointments, linimentums, a collodion, etc. Glycerin is added also to the pilyulny weight, weight for vulval balls for the purpose of giving of plasticity to them. In pure form G. causes irritation of skin and mucous membranes. At addition of water (to 30 — 50%), alcohol, vaseline, lanolin this its property disappears. At the same time G. reduces irritant action of many drugs. It is almost not absorbed by skin, but well absorbed by mucous membranes. The hl is applied. obr. as outside, is more rare as a purgative (on 2 — 5 ml in candles and enemas), for treatment of a trichinosis (on 50 — 150 ml inside), for stimulation of reduction of a uterus. At absorption in blood has toxic effect (causes hemolysis, a haemoglobinuria, metgemoglobinovy heart attacks of kidneys).
Use of glycerin in the histologic equipment
In mix with solution gelatin uses glycerin for filling of the fixed pieces of fabric and for the conclusion gistol, drugs which for some reason or other are undesirable for dehydrating in ethanol. A. L. Shabadash (1939) recommended the drugs painted methylene blue for the best safety of coloring to conclude in glycerin-picrate-gelatin. Can replace ethanol and ether alcohol during the filling of pieces of fabric in photoxylin. Or gelatin with glycerin uses mix of chicken protein for a sticker of cuts on glass. Glycerin is a part of a number of the paints applied in histology. M. A. The baron (1949) suggested to apply to an enlightenment and storage of mikrotrakhiskopichesky drugs of mix of water solutions of glycerin and potassium acetate. At last, glycerin is a part of the Wednesdays used for storage of museum pathoanatomical drugs and for embalming of corpses. See also Histologic methods of a research .
Bibliography: Karrer P. A course of organic chemistry, the lane with it., L., 1960; H of the EU me yanova. N inesmeyanovn. A. Beginnings of organic chemistry, book 1, page 103, M., 1974; Pearce E. A histochemistry, the lane with English, M., 1962.
I. B. Zbareky; K. S. Shadursky (pharm.), Ya. E. Hesin (gist.).