Isolation of L-Asparaginase-Producing Actinomycetes from Soil in Qom: Characterization and Anticancer Activity of L-Asparaginase Against MCF-7 Breast Cancer Cells

Introduction Actinomycetes play an important role in the pharmaceutical and biotechnology industries due to their ability to produce secondary metabolites. Among the most important enzymes they produce is L-asparaginase, a key drug used to treat blood cancer such as acute lymphoblastic leukemia. However, its production is costly and resource-intensive, highlighting the need for the identification of new sources and optimization of its production. The present study aimed to isolate and identify L-asparaginase-producing actinomycetes collected from soil samples in Qom City, Qom, Iran, optimize the conditions for enzyme production, and assess its anticancer effects on the MCF-7 Breast Cancer (BC) cell line in vitro . Materials and Methods In this laboratory study, soil samples were collected from various locations in Qom. Specific culture methods were used to isolate L-asparaginase-producing actinomycetes. The production conditions of the enzyme were optimized with respect to temperature, pH, and carbon and nitrogen sources. The effect of L-asparaginase on the MCF-7 cell line was tested for anticancer activity by the MTT method. Results Among the 65 isolated colonies, three colonies showed the ability to produce L-asparaginase, and the superior strain with higher activity, Streptomyces flavoviridis , was identified. The specific activity of the enzyme increased to 415.25 mg protein/unit after purification, and the analysis by SDS-PAGE indicated a 30 kDa protein band. The enzyme extracted inhibited the growth of MCF-7 BC cells in a dose- and time-dependent manner, with IC 50 of 25.46 and 16.54 µg/mL at 24 and 48 h, respectively. Discussion The findings showed that actinomycetes are suitable sources for producing L-asparaginase with anticancer effects. Conclusion The strains identified in this study could be a suitable solution for the industrial production of this enzyme with lower cost and greater effectiveness.