Production and purification of nattokinase from <i>Bacillus subtilis</i>
Nguyen Hoang Minh, Huynh Thi Quynh Trang, Tran Bao Van, Nguyễn Hoàng Lộc
Abstract
The present study is focused on the production and purification of nattokinase, a fibrinolytic protease, from B. subtilis TH9 (NatTH9) based on an aqueous two-phase system (ATPS) technique. The results showed that the optimal ATPS for NatTH9 recovery was 20% (w/v) polyethylene glycol 6000 and 15% (w/v) potassium phosphate at pH 8. The partitioning coefficient, the partitioning yield, and the activity of NatTH9 were 6.25, 76.7%, and 547.02 U/mg, respectively. The purified NatTH9 demonstrated the ability to degrade fibrin and dissolve the clot. Fibrin zymography showed three clear zones on the gel with molecular weights of approximately 37, 27, and 21 kDa. The optimal pH and temperature of purified NatTH9 were 8 and 39°C, respectively.