3.1. Characterization of viscera enzyme extract
3.1.1. SDS-PAGE and zymography of the crude alkaline protease
A preliminary study on the characterization of the crudeenzyme extract was carried out. In order to estimate the num-ber of proteases in the alkaline crude enzyme extract, samplewas separated by SDS-PAGE, and then the proteolytic activ-ity was revealed by casein zymogram activity staining. Fig. 1shows the separation of various protease bands. The crudeenzyme extract showed three clear zones of protease activitywith different molecular weights. This result suggests that atleast three major proteinases were present in S. scrofa viscera.