Submerged Fermentation of <i>Rhizopus</i> sp. for l‑asparaginase Production in Lymphoma Therapy.

Abstract

l-asparaginase (L-ASNase) has garnered considerable interest in lymphoma therapy due to its mechanism of action, which involves depleting the availability of circulating l-asparagine, a crucial nutrient for malignant cells. Given the notable side effects of commercially available bacterial L-ASNase and the existing challenges in large-scale industrial production, this study focused on identifying and optimizing novel fungal sources for the enzyme. The research methodology involved initial strain screening, development and optimization of a bioreactor system, and subsequent evaluation of enzyme production within a bioprocess. A comprehensive screening of various fungal strains revealed that <i>Rhizopus</i> sp. UPX271019 exhibited the highest specific activity, indicating its significant potential for therapeutic and industrial applications. The study investigated the performance of various bioreactor configurations. A fixed-bed airlift hybrid bioreactor (FB-ALR), operated with an aeration rate of 0.75 vvm, demonstrated superior hydrodynamic and mass transfer performance. A critical observation was the significant role of biofilm formation by <i>Rhizopus</i> sp. UPX271019 within the FB-ALR, which was instrumental in achieving substantial L-ASNase production. The bioprocess yielded an average enzyme activity of 2475 ± 701 U, highlighting the system's effectiveness. These results suggest that the FB-ALR operating with such a strain grown as biofilm is a highly suitable system for future industrial scale-up.