4th Eurasia Biochemical Approaches & Technologies, Antalya, Türkiye, 3 - 06 Kasım 2022, ss.250
L-asparaginase (L-ASNase, EC3.5.1.1) can specifically catalyze L-asparagine conversion to ammonia and
L-aspartic acid. Due to its antineoplastic ability, L-asparaginase has been widely studied as a potential
treatment for acute lymphoblastic leukemia and lymphosarcoma.
1 Although it has the potential to be
widely used in the food and pharmaceutical industries, free L-asparaginases have some disadvantages,
such as short half-life, low stability at high temperature, and lack of reusability. Enzyme immobilization
is a widely used technique to eliminate the drawbacks of free enzymes in industrial applications. Fe3O4
nanoparticles are widely used supports in enzyme immobilization since they have a large surface area
and are easily separated from reaction system by magnet.2 In this study, L-asparaginase was covalently
immobilized on modified Fe3O4 nanoparticles. The optimum pH and temperature of free and
immobilized L-asparaginase preparations were determined as 8.5 and 50 C for the both preparations.
The thermal stability experiments showed that the thermal stability of immobilized L-asparaginase
increased by 30 folds at 50 °C compared to the free enzyme. The immobilized L-asparaginase remained
80% of its initial activity after 10 reuses.