Hydrolysis
The hydrolysis ( ancient Greek ὕδωρ hydor "water" and λύσις Lysis " solution, dissolution, termination ") is the cleavage of a ( bio) chemical compound by reaction with water. Here (formal) is given a hydrogen atom to the a " split-off piece ," bound the remaining hydroxyl radical to the other cleavage product. The reversal of hydrolysis, a condensation reaction. If in the reaction, the solvent is water, one of the hydrolysis to the solvolysis.
Notwithstanding the above definition, the term hydrolysis, also Salzhydrolyse was called, used by Arrhenius to describe basic or acidic reactions that occur upon release of salts, the acid or base residues are derived from weak acids or weak bases. The hydrolysis is here a reversal of neutralization. See also acid-base concept according to Arrhenius.
Examples
- Hydrolysis of alkyl fluorides
- Hydrolysis of the carboxylic acid chlorides and carboxylic acids to hydrogen chloride
- Hydrolysis of benzyl chloride to benzyl alcohol and hydrogen chloride
- Hydrolysis of calcium carbide to acetylene and calcium hydroxide
- Hydrolysis of carboxylic acid amides to carboxylic acids
- Hydrolysis of carboxylic anhydrides to give carboxylic acids
- Hydrolysis of vegetable or animal fats to glycerol and fatty acids
- Ester hydrolases catalyze the hydrolysis of one enantiomer of a chiral ester to carboxylic acid and alcohol, the other enantiomer is not hydrolyzed
- Hydrolysis of acetals to aldehydes and alcohols
- Hydrolysis of ketals to ketones and alcohols
- Hydrolysis of the Grignard compounds
- Hydrolysis of isocyanides
- Hydrolysis of isothiocyanates
- Hydrolysis of nitriles via carboxylic acid amides to carboxylic acids
- Hydrolysis of oximes to carbonyl compounds (aldehydes or ketones) and hydroxylamine
- Hydrolysis of imines to carbonyl compounds (aldehydes or ketones) and primary amines
- Hydrolysis of hydrazones to carbonyl compounds (aldehydes or ketones) and hydrazine
- Hydrolysis of ortho-carboxylic acid esters
- Hydrolysis of oxiranes
- Partial hydrolysis of peptides, in which only some of the peptide bonds are cleaved
- Hydrolysis of sulfonyl chlorides
- Hydrolysis of Tetrachlorosilane to silicon dioxide and hydrogen chloride
- Hydrolysis of tert -butyl chloride
Most of the above listed hydrolysis take place faster and better, if one carries out the reaction in acidic or basic medium, rather than at neutral pH. Examples include the acid hydrolysis of esters, which is the reverse reaction to the esterification, as well as running in the basic hydrolysis
Enantioselective hydrolysis
Esters of chiral carboxylic acids or chiral alcohols may be enantioselectively hydrolysed under the influence of lipases. Here, enantiomerically pure alcohols or enantiomerically pure carboxylic acids. Analogously, racemic amides enantioselectively hydrolyze in the presence of acylase. The method is industrially applied to the production of the amino acid L- methionine from N-acetyl -DL- methionine.
Hydrolysis of biomolecules
Hydrolysis many biomolecules (eg proteins, disaccharides, polysaccharides or lipids) are broken down into their components in metabolism (monomers ), usually catalyzed by an enzyme ( hydrolase ).
A significant hydrolysis reaction which are proteins energy to mechanical work, transport processes and the like, is the cleavage of ATP to ADP and phosphate radical.
In the analysis of amino acid composition of proteins, purified proteins are hydrolyzed under the exclusion of air and at temperatures > 100 ° C by high concentrations of hydrochloric acid. By the hydrolyzate of the protein can - under knowledge of the stability of the released amino acids under standard conditions and correction factors - are closed to the proportion of each amino acid in the peptide-bound structure of the protein.