What would you expect the pH optimum to be for an enzyme secreted into your stomach?

Question

What would you expect the pH optimum to be for an enzyme secreted into your stomach?

Answer 1

anywhere from pH2 to pH4--depends on where exactly in the stomach--fundus, body, antrum, etc

Answer 2

The stomach is usually a highly acidic environment due to gastric acid production and secretion which produces a luminal pH range usually between 1 and 4 depending on food intake and other factors. Such an environment is able to break down large molecules (such as from food) to smaller ones so that they can eventually be absorbed from the small intestine. The stomach can produce and secrete about 2 to 3 litres of gastric acid per day

pH in the stomach is very acidic and inhibits the breakdown of carbohydrates while there. The strong acid content of the stomach provides two benefits, both serving to denature proteins for further digestion in the small intestines, as well as providing non-specific immunity, retarding or eliminating various pathogens.


The enzymes that get secreted in the stomach are called gastric enzymes. These are the following:

1.Pepsin is the main gastric enzyme. As it breaks proteins into smaller peptide fragments, it is a peptidase.
2.Gelatinase, degrades type I and type V gelatin and type IV and V collagen, which are proteoglycans in meat.
3.Gastric amylase degrades starch, but is of minor significance(because the high acid content of the stomach inhibits the enzyme activity).
4.Gastric lipase is a tributyrase by its biochemical activity, as it acts almost exclusively on tributyrin, a butter fat