Hoda M. Soliman, Noura El-A. El-Naggar* and Sara M. El-Ewasy Pages 23 - 37 ( 15 )
Background: L-asparaginase is one of the most widely used chemotherapeutic agents for the treatment of a variety of lymphoproliferative disorders and particularly acute lymphoblastic leukemia. Due to increased applications of L-asparaginase in several industrial fields including food processing and medical fields, its production needs to be increased to several folds.
Objectives: The aim was (i) to identify the significant factors which affect L-asparaginase production by Streptomyces fradiae NEAE-82 and (ii) to achieve higher production of L-asparaginase.
Methods: Sixteen assigned factors and three dummy factors were screened using Plackett-Burman experimental design to determine the most important factors for the production of L-asparaginase by Streptomyces fradiae NEAE-82.
Results: L-asparagine was determined to be the most significant positive independent factor (P-value 0.0092) affecting L-asparaginase production by Streptomyces fradiae NEAE-82 followed by pH and NaCl with significant P-values of 0.0133 and 0.0272; respectively. These factors were further optimized by Box-Behnken experimental design. The optimized fermentation conditions, which resulted in the maximum L-asparagine activity of 53.572 UmL-1 are g/L: dextrose 4, L-asparagine 15, KNO3 2, MgSO4.7H2O 0.5, K2HPO4 1, FeSO4.7H2O 0.02, NaCl 0.2, ZnSO4 0.01 and inoculum size 2 %, v/v for 7 days incubation at temperature 37°C, agitation speed 100 rpm, pH 8.5.
Conclusion: A total of 3.41-fold increase in the production of L-asparaginase was achieved in the medium after statistical improvement (53.572 UmL-1) as compared to the unoptimized basal medium used prior to the application of Plackett-Burman (15.704 UmL-1).
L-asparaginase production, Streptomyces fradiae NEAE-82, Plackett-Burman, Box-Behnken designs, lymphoblastic leukemia, lymphocytes.
Department of Botany, Faculty of Science, Mansoura University, Mansoura 35516, Department of Bioprocess Development, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, Alexandria 21934, Department of Bioprocess Development, Genetic Engineering and Biotechnology Research Institute, City of Scientific Research and Technological Applications, Alexandria 21934