Stability of trypsin from Z. ophiocephalus in the presence of various commercial
laundry detergents. The enzyme at 200 U/ml was incubated 1 h at 30 and
40 ◦C and pH 9.0 in the presence of liquid detergents (a) diluted 100-fold in tap
water (1/100) and solid detergents (b) at a final concentration of 7 mg/ml, and the
remaining activities were determined at pH 9.0 and 60 ◦C using casein as a substrate.
Enzyme activity of control sample without any detergent, incubated under
the similar conditions, was taken as 100%.