Purification and Biochemical Characterization of L-Asparaginase from Aspergillus niger and Evaluation of Its Antineoplastic Activity

L-asparaginase is a chemotherapeutic drug used in the treatment of lymphoblastic leukemia. In the present study, the extracellular L-asparaginase produced by strain Aspergillus niger was purified, characterized. Moreover, its antiproliferative activity was evaluated. The apparent molecular weight of the enzyme was found to be 136 kDa. The optimal pH and temperature for the enzyme were 9.0C and 40C, respectively. The enzyme retained 100 % of the activity at 40C for 120 min. L-asparaginase against human normal cells did not show cytotoxicity. However, in the human leukemia cell line A431 the antiproliferative effects of L-asparaginase was observed after 96 h of incubation. For the first time, an L-asparaginase from fungus was evaluated as an antitumor agent in human cells lines and further investigations should be conducted to improve the knowledge about this enzyme.