- /huy drol"euh sis/, n., pl. hydrolyses /-seez'/.chemical decomposition in which a compound is split into other compounds by reacting with water.[1875-80; HYDRO-1 + -LYSIS]
* * *Chemical reaction in which water (H2O or HOH) and another reactant exchange functional groups to form two products, one containing the H and the other the OH. In most hydrolyses involving organic compounds, the other reactants and products are neutral; for example, an ester can be hydrolyzed to form a carboxylic acid and an alcohol.Such reactions are often accelerated by enzymes (as in much of digestion and metabolism in general) or other catalysts. In hydrolyses of compounds with ionic bonds, the nonwater reactants are salts, acids, or bases, participating in dissociation reactions.
* * *in chemistry and physiology, a double decomposition reaction with water as one of the reactants. Thus, if a compound is represented by the formula AB in which A and B are atoms or groups and water is represented by the formula HOH, the hydrolysis reaction may be represented by the reversible chemical equation AB + HOH ⇌ AH + BOH. The reactants other than water, and the products of hydrolysis, may be neutral molecules—as in most hydrolyses involving organic compounds—or ionic molecules, as in hydrolyses of salts, acids, and bases.Hydrolysis involving organic compounds may be illustrated by the reaction of water with an ester of a carboxylic acid; all such esters have the general formula RCO−OR′, in which R and R′ are combining groups (for example, if R and R′ both represent the methyl group, CH3, the ester is methyl acetate). The hydrolysis involves several steps, of which the slowest is the formation of a covalent bond between the oxygen atom of the water molecule and the carbon atom of the ester. In succeeding steps, which are very rapid, the carbon–oxygen bond of the ester breaks and hydrogen ions become detached from the original water molecule and attached to the nascent alcohol molecule. The whole reaction is represented by the equationRCO−OR′ + H2O → RCO−OH + R′−OH, in which RCO−OH denotes a molecule of a carboxylic acid, R′−OH denotes a molecule of an alcohol, and the dashes represent covalent bonds that are broken or formed during the reaction.A characteristic feature of the hydrolysis of esters (ester) and of most other organic compounds is that a third substance, ordinarily an acid or a base, increases the rate at which the chemical change takes place. In the biochemical process of digestion, enzymes (enzyme) secreted by the digestive tract catalyze the hydrolysis of complex molecules into forms that the body organisms can assimilate. Proteins are decomposed to amino acids, fats to fatty acids and glycerol, and starches and complex sugars to glucose and other simple sugars; enzymes such as lipases, amylases, and proteinases catalyze the hydrolysis of fats, carbohydrates, and proteins, respectively.Hydrolysis involving ionic compounds may be illustrated by the chemical changes occurring in an aqueous solution of the salt sodium acetate. In solution, the ionic constituents of the salt (the acetate ion and the sodium ion) separate; water molecules combine with the acetate ions to form acetic acid and hydroxide ions. Acetic acid dissociates reversibly into acetate ions and hydrogen ions, but only to a very small extent, so that the ionic content of the solution is largely sodium and hydroxide ions. Hence, the solution exhibits basic properties (i.e., turns red litmus paper blue).
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Hydrolysis — is a chemical reaction during which one or more water molecules are split into hydrogen and hydroxide ions which may go on to participate in further reactions. [Compendium of Chemical Terminology, [http://goldbook.iupac.org/H02902.html… … Wikipedia
Hydrolysis — Hy*drol y*sis, n. [Hydro , 1 + lysis.] (Chem.) A chemical process causing the splitting of a chemical bond by the addition of the elements of water. Where the bond which is split is not part of a ring structure, this process causes formation of… … The Collaborative International Dictionary of English
hydrolysis — hydrolysis. См. гидролиз. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) … Молекулярная биология и генетика. Толковый словарь.
hydrolysis — chemical decomposition by water, 1880, formed in English from HYDRO (Cf. hydro ) + Gk. lysis a loosening, a dissolution, from lyein to loosen, dissolve (see LOSE (Cf. lose)) … Etymology dictionary
hydrolysis — ► NOUN Chemistry ▪ the chemical breakdown of a compound due to reaction with water. DERIVATIVES hydrolytic adjective … English terms dictionary
hydrolysis — [hī dräl′ə sis] n. pl. hydrolyses [hī dräl′isēz΄] [ HYDRO + LYSIS] a chemical reaction in which a substance reacts with water so as to be changed into one or more other substances, as a starch into glucose, natural fats into glycerol and fatty… … English World dictionary
hydrolysis — n. (pl. ses ) chemical decomposition by addition of water. ♦ hydrolysate, n. product of hydrolysis. ♦ hydrolyse, v.t. ♦ hydrolytic, a … Dictionary of difficult words
hydrolysis — hidrolizavimas statusas Aprobuotas sritis pašarai apibrėžtis Medžiagos skaidymas į paprastesnius cheminius junginius, naudojant tam tikrus apdorojimo vandeniu, rūgštimis, šarmais ar kitais reagentais būdus. atitikmenys: angl. hydrolysis vok.… … Lithuanian dictionary (lietuvių žodynas)
hydrolysis — hidrolizė statusas T sritis chemija apibrėžtis Skaidymas vandeniu. atitikmenys: angl. hydrolysis; hydrolytic cleavage rus. гидролиз; гидролитическое расщепление ryšiai: sinonimas – hidrolizinis skaidymas … Chemijos terminų aiškinamasis žodynas
hydrolysis — hidrolizė statusas T sritis chemija apibrėžtis Grįžtamoji jonų reakcija su vandeniu. atitikmenys: angl. hydrolysis rus. гидролиз … Chemijos terminų aiškinamasis žodynas