Studies on the stability of protease from Bacillus sp. and its compatibility with commercial detergent

Abstract

Enzymes, and particularly proteases, have become an important and indispensable part of industrial processes such as laundry detergents, pharmaceuticals and food products. Detergents such as Tide®, Ariel® and Biz® contain proteolytic enzymes, most of them produced by members of the genus Bacillus. This paper describes the compatibility of protease produced by the thermophilic Bacillus sp, with commercial laundry detergent. Stability studies indicated that this enzyme retained about 95% and 74% of its maximum activity after 1h at 60oC in the presence of glycine in combination with MnSO4 and CaCl2, respectively. No inhibitory effect was observed at 1.0-5.0 mM of EDTA. Triton X-100 inhibited the enzyme in all the concentrations tested. The enzyme was unstable in a 5% (v/v) concentration of peroxide solution. The protease retained more than 80% and 65% of its activity after 30 min incubation at 60oC in the presence of Tide® and Cheer® detergents, respectively. After supplementation of CaCl2 (10 mM) and glycine (1 mM), the enzyme in Tide® detergent retained more than 85% of its activity after 1h. Based on these findings, Bacillus sp. protease shows a good potential for application in laundry detergents.