来源:灰色链霉菌。 Unite definition: The unit of non-specific protease activity is in general the enzyme activity that increases the rate of release of folin-positive amino acids and peptides from casein at a temperature of 40°C and pH 7.5 by a quantity equivalent to a given amount of tyrosine per minute. For the unit designated ‘U’, that quantity of tyrosine is 1 µmol/min