ABSTRACT
The enzymes are either exoenzymes or endoenzymes. Exoenzymes, which are a few in number, are released from the cell and act on the substrates. Enzymes required for the hydrolysis of cellulose, starch, pectin, lipid, casein, and gelatin belong to the category of exoenzymes. Endoenzymes are also involved in carbohydrate fermentation, litmus milk reactions, hydrogen sulfide production, nitrate reduction, catalyzed reaction, urease test, oxidase test, IMViC test, and the triple sugar iron test. Amylase is an exoenzyme that hydrolyzes starch, a polysaccharide into maltose, a disaccharide and some monosaccharides such as glucose. Degradation of cellulose is brought about by microbes by the secretion of extracellular enzyme, cellulase. It is a complex enzyme composed of at least three components, viz., endoglucanase, exoglucanase and a ß-glycosidase. Intercellular enzymes are utilized by the cell for metabolic degradation of carbohydrates. Two examples of such enzymes are maltase and lactase.
