Preparation of Chitosan Conjugated Protease Used for Shrink Resistance of Wool and Its Properties

Abstract:

Chitosan was covalently coupled to protease(Savinase 16L) with water-soluble carbodiimide to enlarge its molecular weight,with the purpose of reducing enzymatic damage to wool fibres in anti-felting finishing.It was found that the secondary and the whole structures of the modified protease were much more regular and compact than the native one.The conjugated protease presented a lower affinity towards casein with an increase in Km from 20.62 g/L to 35.21 g/L.There was no change in optimum temperature(55 ℃)for the modified protease while its thermal stability at 55 ℃ was improved.Compared to the native enzyme,the modified protease displayed higher stability above 70℃.