A white or almost white, crystalline or amorphous powder. Chymotrypsin 1000USPis a proteolytic enzyme obtained by the activation of chrymotrypsinogen extracted from the pancreas of beef. In solution it has maximal enzymic activity at about pH8; the activity is reversibly inhibited at pH 3, at which pH it is most stable. The animals from which chymotrypsin is derived must fulfil the requirements for the health of animals suitable for human consumption to the satisfaction of the competent authority; furthermore the tissues used shall not include any relevant international or, where appropriate, national legislation. It must have been shown to what extent the method of production allows inactivation or removal of any contamination by viruses or other infectious agents.