Answer: 1. The digestive power of pepsin is greatest at the acidity of normal gastric juice (pH 1.5–2.5). 1.0–2.0
The optimum pH for pepsin activity of 1.0–2.0 is maintained in the stomach by HCl. When the pH of the medium increases to values greater than 3.0, pepsin is almost completely inactivated. 2. The optimum pH for the enzymatic activity of salivary amylase ranges from 6 to 7. Above and below this range, the reaction rate reduces as enzymes get denatured. The enzyme salivary amylase is most active at pH 6.8. around 7
Salivary α‐amylase has a short‐lived action. In fact, it is swallowed with chewed food and subsequently inactivated by extremely low gastric pH; amylase in fact has an optimal pH around 7, and the pH of saliva is generally between 6.4 and 7.0.
