**3.1 Protopectinase**

Protopectinase, which catalyzes the solubilization of protopectin in the presence of water to release soluble pectin. The catalyzation process could occur through the reaction at sites having three or more non-methylated molecules of GalA, hydrolyzing the glycosidic bond [31]. According to the catalytic action, these enzymes are classified into two types:

