Process Biochemistry, Vol.64, 213-220, 2018
The effect of immobilization, drying and storage on the activity of proteinases immobilized on modified cellulose and chitosan
Nowadays the wound healing dressings based on modified cellulose, chitosan and various immobilized therapeutic agents are commonly used. This study disclosed the preparation of dialdehyde cellulose (DAC), immobilization of chitosan and different enzymes (trypsin, bromelain, and proteolytic complex from hepatopancreas of crab) and demonstrated the analysis of enzymatic activity of obtained materials during immobilization, drying and storage. The research also covered a possible structural scheme of obtained material and the methods of its production. The exponential equations were presented as a model, developed as a mathematical description of enzymatic activity loss, which was studied during the stated processes. The optimal conditions for the product with the preservation of enzymatic activity were chosen on the basis of developed equations. It was stated that chitosan stabilizes the analyzed proteinases during drying and storage: for proteolytic complex from hepatopancreas of crab (PC) over 150%, and for bromelain - 600%. The main destructive factor for the obtained enzymatic preparation during storage is water (in immobilized products). The humidity of the used materials was 5%, therefore 50 mg of water per 1 mg of immobilized protein was reported to be the critical concentration that caused the loss of enzymatic activity of the studied enzymes.
Keywords:Immobilization;Chitosan;Chitosan-coated dialdehyde cellulose;Hydrolases;Wound healing;Drug design