Evaluation of biochemical properties of the purified trypsin from common kilka (Clupeonella cultriventris caspia) intestine

In this work, the biochemical properties of the purified trypsin from common kilka (Clupeonella cultriventris caspia) intestine including optimum temperature and pH, thermal and pH stability, effect of inhibitors, metal ions, oxidizing agents and surfactants were assayed. According to the obtained results, optimum temperature and pH of the trypsin were recorded at 60°C and 8 respectively. The stability of the trypsin was well preserved at temperatures of up to 50°C and pH from 7.0 to10.0. SBTI and TLCK, two specific trypsin inhibitors, had a completely inhibition effect on the enzymatic activity (P<0.05). The enzyme activity was significantly increased in the presence of Ca+2 and Mg+2 and decreased by Cu+2, Ba+2, Co+2 , Zn+2 , Fe+2 and Al+3 (P<0.05). Na+and K+ did not show any significant effect on the activity of trypsin (P>0.05). The enzymatic activity was significantly increased in presence of surfactants including saponin and sodium cholate and showed a significant decrease in presence of SDS and oxidizing agents like sodium perborate and hydrogen peroxide (P<0.05). Therefore, the results of our study can contribute to the clear understanding of the purified trypsin from common kilka intestine for application in different industries in future.