Enzymes are special types of proteins, present in all living organisms, that facilitate the acceleration of chemical reactions. In these reactions, enzymes act upon specific molecules, called substrate, which are converted into different molecules called products.
Enzymes are involved in many different processes. We will now focus on the roll that enzymes have in the digestive system. Digestive enzymes are capable of degrading large molecules as starch or protein, into smaller ones, so that they can be absorbed in the gastrointestinal tract. This improves the nutrient digestibility.
Different organs of the gastrointestinal tract produce the enzymes that are involved in the digestive process. These are called endogenous enzymes, as they are produced by the animal. Feed enzymes are known as exogenous enzymes, as they are added to the diet to aid the endogenous enzymes in the digestive process.
Exogenous enzymes are selected from nature and processed into a commercial product that can be used as feed enzymes. In this process “Source microorganisms” are selected. These are the microorganisms from which gene expression the desired enzymes are extracted. Additionally,“Expression microorganisms” are selected to scale up the production of enzymes using the submerged fermentation process