Where do enzymes function?
Enzymes are proteins and subject to the rigors of the digestive system, and are themselves digested. Prior to inactivation they must accomplish the degradation of the target substrate. A critical component is pH; enzymes will not function outside their preferred range, and will be progressively denatured outside this range. Food entering the anterior digestive tract (crop/proventricus/ventriculus in chickens; stomach in pigs) will initially be mildly acidic and near optimum for fungal enzymes (5.0-5.5). The pH will drop as the feed is acidified with gastric secretion, with activity declining and ultimately reaching a point where they activity is irreversibly lost. Only a fraction of the enzyme will escape to the small intestine. Which enzymes are preferred, fungal or bacterial? Most enzyme products offered by enzyme manufacturers for feed purposes are produced by fungi rather than bacteria. An exception is amylase which in many products is bacterial in origin. Fungi prefer a lower pH t
