Thank you for reporting, we will resolve it shortly
Q.
The optimum $pH$ for pepsin is
AMUAMU 2015Digestion and Absorption
Solution:
Pepsin is a protease enzyme that functions in acidic environment of stomach having $pH$ of about $1.5-2$. It exhibits maximal activity at $pH\, 2.0$ and is inactive at $pH\, 6.5$ and above. However, pepsin is not fully denatured or irreversibly inactivated until $pH\, 8.0$ is reached.