Egypt. J. Vet. Sci. Vol. 53, No. 1, pp. 9-14 (2022) Introduction L-asparaginase (L-a) is an anti- neoplasm agent which is widely isolated from microbial sources with specifc physicochemical properties. Lymphoblastic leukemia (ALL) is a leukemia only ripens in infant [1,2]. The enzyme L-asparaginase is used to treat ALL [3]. Seek evacuation From asparagine, regular cells are synthesized through synthesis [4,5]. Cancer cells still lack asparagine synchronization, Ultimately causes defcit of asparagine in these cells leads to the unavailability of asparagine for synthesis of protein become to their death [6-8]. L-asparaginases are widely distributed and are the main origin of L-asparaginase for the testing of Escherichia coli and Erwinia bacteria [9,10]. L-asparaginase has been observed in many bacterias, the purifcation and characterization of this enzyme from bacteria around plant roots are important because in plants, L-a is the famous store of nitrogen and the presence of enzyme-producing bacteria around plant roots is higher [11,12]. Therefore, screening of samples from new and diverse sources is required to isolate microbes that have the ability to produce enzymes with new properties [13,14]. The aim of this study was to isolate bacteria from different soil sources and fnally produce L-asparaginase from it for anti- cancer purposes. L -ASPARAGINASE is an anti-neoplasm agent. This agent is classifed as an enzyme compound. L-asparaginase is used in medicine as well as in the food industry. Microbial strains that are producing L-Asparaginase can be found in many habitats such as soil. The aim of this study was to fnd isolates producing L-asparaginase enzyme with high ability to inhibit cancer cells. Bacteria of the Actinobacter family were isolated from the soil samples around the roots of the plants in the actinomycet isolation medium. Then, the bacteria were isolated and extracted by screening in M9 medium. Isolates were identifed using16S PCR sequencing method. Three isolates of ASP and B and C showed the highest enzyme production, which showed a molecular weight of 43 kDa and in terms of enzymatic activity112. 572 IU/ml, 99.706 IU/ml, 138.572 IU/ml respectively. These three isolates with sequence analysis was similar to Streptomyces favoviridis and Streptomyces griseus and Streptomyces hypolyticus respectively. Isolate C showed good effects in inhibiting cell MCF-7, HepG-2. There are various isolates enzyme production power in nature and Actinobacter family has shown more ability to produce various enzymes and metabolites and the isolates isolated in this study are used for industrial enzyme production. Keywords: L-Asparaginase, Anti-cancer activity, Actinobacteria, Rhizosphere, Plants. 2 Manufacture of L-Asparaginase by Actinobacteria Isolated from Rhizosphere of Plants in Tehran with Strong Anti-cancer Activity Masoumeh Davarpanah 1 , Ronak Bakhtiari 1 , Ali Javadi 2 and Seyyed Saeed Eshraghi 1 1 Department of Pathobiology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. 2 Department of Basic Medical Sciences, Qom Medical Sciences Branch, Islamic Azad University, Qom, Iran. Egyptian Journal of Veterinary Sciences https://ejvs.journals.ekb.eg/ Corresponding author: Seyyed Saeed Eshraghi, E-mail: esraghi1398@gmail.com, Tel: +98-2188994823 (Received 11/08/2021; accepted 25/08/2021) DOI. 10.21608/ejvs.2021.89728.1263 ©2022 National Information and Documentation Centre (NIDOC)