Store desiccated at -15℃ or below. Allow to come to room temperature before opening. Before returning to storage, redesiccate under vacuum over silica gel for a minimum of four hours. Re-seal before returning to -15℃ or below.
Unit definition:
That amount of enzyme that will catalyse the production of 1mg of purpurogallin from pyrogallol in 20 seconds at 20℃ and pH 6.0.
Activity:
Not less than 250U/mg material
RZ (E403/E275):
Greater than 3.0
Solubility:
Dissolves readily at 5mg/ml in 0.1M Potassium phosphate buffer, pH 6.0, to give a clear solution.