PARABEN (synonym: n-aminobenzoic acid, vitamin H 1 ) — growth a factor for a number of microorganisms, the metabolic predecessor of the folic acid synthesized by these microorganisms. Animals and the person are not capable to use P. to. for synthesis folic acid (see), to-ruyu shall receive with food therefore P. to. for animals and the person vitamin is not. P.'s action to. as growth factor of a number of pathogenic microorganisms is suppressed with sulphamide drugs what their broad use as pharmaceuticals is based on.
In the medical practician P. to. as did not find individual substance of the broad use though it was used as medicine at a sapropyra (in doses of 4 — 6 g a day) and at poisonings with drugs of arsenic, antimony, mercury, boric to - you. In the form of 15% of ointment P. to. apply at sunblisters. In pharmaceutical industry of P. to. use at synthesis of mestnoanesteziruyushchy means; the hydrochloride of its diethylaminoethyl ether (novocaine) is widely used in medicine.
The item to. represents white crystal matter, t ° pl 186 — 187 °, badly a rastvorima in water, well a rastvorima in ethanol and ether. Pier. weight (weight) 137. The item to. — chemically resistant substance: does not collapse at boiling in acid and alkaline environments. The item to. receive oxidation of n-nitrotoluene with the subsequent recovery of the n-nitrobenzoic to - you.
The item to. it is eurysynusic in the nature. It contains in animal and vegetable fabrics, in foodstuff, in microorganisms. In significant amounts of P. to. it is found in a liver, kidneys, milk, yeast, mushrooms, rice bran, etc.
by P. to., got into a human body with food, it is partially soaked up in a small bowel, partially used by microflora of a large intestine for synthesis folic to - you.
Blood of the person contains from 2 to 70 mkg of P. to. in 100 ml. A significant amount of P. to. it is removed with a stake (to 250 mkg a day) and urine. P.'s maintenance to. in blood and removal with urine increase at patients with cardiovascular diseases, decrease at hron, hepatitis, cholecystitis and inf. hepatitis.
Standard daily rate of P. to. for the person it is not established. Reliable methods of definition of P. to. in biol, substrates is not present.
Bibliography: Vitamins, under the editorship of M. I. Smirnov, page 460, M., 1974.
V. B. Spirichev.