Pectin Depolymerase Activities Associated with Cell Walls from Cicer arietinum L. Epicotyl

Abstract

The hydrolytic activity of the proteins extracted with 3 M LiCl from chick-pea (Cicer arietinum) cell walls to pectic fractions extracted with 50 mM trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid (CDTA) and 50 mM sodium carbonate was studied. The pectic fractions contained acidic polysaccharides with high molecular mass (higher than 5 × 103 kDa), mainly composed of uronic acids, galactose, arabinose and rhamnose. The extracted proteins depolymerized the pectic polysaccharides and also a commercial preparation of polygalacturonic acid from citrus, detected by a decrease in their viscosity and a shift of their molecular mass distribution. The extract was able to depolymerize a uronic acid-rich component in all the cases, although in different extent. Also, with regard to the CDTA-soluble pectins, a degradation of polyuronide and a shift of the molecular mass distribution of arabinogalactan was observed.