Fusarium sp. L-Asparaginases: purification, characterization and potential assessment as anti-leukemic chemotherapeutic agent

Asparaginases play an important role in the treatment of leukemia. It is part of chemotherapy in the treatment of leukemia in the last three decades. L-Asparaginase isolated from Fusarium sp. isolated from soil and purified using ammonium sulfate precipitation and Sephadex G 100. Characterization of the crude enzyme revealed it is a metalloprotease inhibited by EDTA. Hg2+, Cd2+, and Pb2+ also inhibited the enzyme. Mg2+, Zn2+ and Ca2+ activated L. asparaginase. Further, the kinetic studies of purified enzyme were carried out. Vmax and Km and were 0.031 M and 454 U/mL, respectively. The optimum temperature was 30°C, optimum pH was 7. Concerning substrate specificity; gelatin and casein in addition to L-asparagine were tested. The enzyme was found to be non-specific, could hydrolyze all tested substrates at different rates. Maximum enzyme activity was recorded in the case of L-asparagine, followed by Casein and gelatin, respectively. The molecular weight of L-Asparaginase was 22.5 kDa. The Anti-leukemic cytotoxicity assay of the enzyme against RAW2674 leukemic cell lines by MTT viability test was estimated. The enzyme exhibited anti-leukemic activity with IC50 of 70 Uml− 1 and relative viability 70 % of control. The current work presents additional information regarding the purification and characterization of the enzyme produced by Fusarium sp. and its evaluation as a potential anti-leukemic chemotherapeutic agent.

Synthesis, characterization and cytotoxicity of palladium(II) complex of 3-[(2-hydroxy-benzylidene)-amino]-2-thioxo-imidazolidin-4-one

The polydentate ligand, 3-[(2-hydroxy-benzylidene)-amino]-2-thioxo-imidazolidin-4-one, was synthesized by intermolecular cyclocondensation reaction of 2-hydroxybenzaldehyde thiosemicarbazone and ethylchloroacetate. Novel palladium(II) complex was obtained by nucleophilic substitution of both DMSO ligands from cis-[Pd(DMSO)2Cl2] with iminic nitrogen and thiolactamic sulfur from ligand. The structure of compounds was characterized on the basis of their spectral data. The cytotoxic activity of the ligand and palladium(II) complex was studied on tumor cell lines: human colon carcinoma HCT-116 and SW-480 cells using MTT viability test. The results show that investigated palladium(II) complex has significantly greater cytotoxic effect compared to ligand.