Effect of High Pressure Homogenization on the Activity and Stability of Protease from Bacillus Licheniformis LBA 46 in Different pH Values

Alkaline proteases have great importance in the pharmaceutical, textile, food industries and research studies. High pressure is an emerging and relatively new technology that is capable of modifying various molecules. The use of High Pressure Homogenization (HPH) has been widely evaluated in the modulation of enzyme activity, either to inactivate, improve or stabilize its activity. The effect of HPH treatment on Bacillus licheniformis LBA 46 semi-purified protease activity was investigated at different pH values and temperatures of activity. The enzyme was treated up to 200 MPa at pH 4, 7 and 9 and the residual activity was evaluated on the day of the treatment and after 24 h of refrigerated storage. The protease activity and stability measured at 40, 60 and 90°C between the control and the treated samples showed similar residual activity values. This suggests that the enzyme was resistant to the HPH treatment (50-200 MPa). Though HPH is a promising method to change enzymes characteristics, it was not able to change the protease from Bacillus licheniformis LBA 46.