The catalyst also known as catalyst, in the definition of the junior middle school stage is to change the rate of a chemical reaction, and quality, chemical composition and properties of the material itself remained unchanged before and after participating in a chemical reaction. For example, manganese dioxide can be used as hydrogen peroxide (hydrogen peroxide) decomposition catalysts. The catalyst consists of positive catalysts and inverse catalyst, catalyst to contribute to the reaction to the positive direction, help to reverse direction in the inversecatalyst reaction.
Enzymes are biocatalysts, organic plant, animal and microorganism has a catalyticability (the vast majority of proteins. But a small amount of RNA also has abiological catalysis), formerly known as enzyme. Chemical reactions of the bodyalmost all in under the catalysis of enzyme.
The enzyme catalysis has a selectivity. For example, starch. Enzymes that catalyze the hydrolysis of starch into dextrin and maltose, protease catalyzed hydrolysis of proteins into peptides. Living organisms use them to accelerate the chemicalreactions in the body. Without the enzyme, many chemical reactions in living organisms will be slow, difficult to sustain life. At about 37 ℃ temperature (body temperature), enzyme working condition is the best.
If the temperature is higher than 50 ℃ or 60 ℃, enzyme will be destroyed and can no longer function. Therefore, using biological detergent enzymes to break downstains on clothing, the use of the most efficient at low temperature. Enzyme inphysiology, medicine, agriculture, industry and so on, are of great significance. At present, the application of enzyme preparation is more widely. For example:enzyme preparation can be used as a catalyst in industry, some enzyme orprecious medicine.