3.2.2. Stability of the S. scrofa proteases in the presence ofsolid and liquid detergents
To check the compatibility and stability of S. scrofa proteasestoward detergents, enzymes were preincubated in the pres-ence of various commercial laundry detergents of differentcomposition for 1 h at 30 and 40◦C. The data presented inFig. 4a showed that S. scrofa proteases are highly stable in thepresence of solid detergents at a concentration of 7 mg/ml.These proteases exhibited higher stability in Ariel (100%),Axion (97%) and Shems (83%) but were less stable in NewDet(64%) and Nadhif (28%) at 30◦C. At 40◦C S. scrofa proteaseswere found to be less stable than that at 30◦C.Data presented in Fig. 4b also showed that S. scrofaproteases are extremely stable in the presence of liquid deter-gents, retaining 100% of their initial activity with Carrefour,95% with Lav+ and more than 80% with Tex’til and Nadhifperfect even after 1 h incubation at 30◦C.