Q. Do enzymes act better under basic or acid pH?

Most enzymes act in pH between 6 and 8, a range that corresponds to the general acidic level of blood and cells. There are enzymes, however, that act only under very basic or very acid pH. So enzyme activity depends on pH interval.

In the stomach, for example, the gastric juice has a very low pH, around 2, and there the enzyme pepsin acts to intensively absorb proteins. In the duodenum, pancreatic secretions increase the pH of the enteric juice for the action of other digestive enzymes, for example, trypsin.