Enzyme Unit Definition Conversions
Dispase CHNP Thermolysin Azocasein Units (AUC) One AUC catalyzes an A440 equivalent to 1mg/mL
of azocasein per mL per minute at 37°C

1 Dispase Unit = 181   Protease Units (PU)
Neutral Protease Units
(NPU)
An increase of 1 fluorescent unit per minute at 35°CBSAfromconjugatethecleava.
Protease units (PU) One protease unit catalyzes the hydrolysis of
casein to produce color equivalent to 1.0 µmole tyrosine per min at pH 7.5 at 37°C.
Dispase Unit One dispase unit catalyzes the hydrolysis of
casein to produce 181 µmole tyrosine per min at pH 7.5 at 37°C.
DMC-U units One DMC-U catalyzes the cleavage of 1 μmole of peptide bonds from dimethyl case in (DMC), at  25°C, pH 7.0
Caseinase Units One caseinase unit will hydrolyze casein to
produce color equivalent to 1.0 µmole (181 µg) of  tyrosine per 5 hours at pH 7.5 at 37°C
Table 3: Summary of common neutral protease specific activity units [42-45].