Low-cost agro-industrial sources as a substrate for the production of l-asparaginase using filamentous fungi

Synergistic effects of ternary mixture formulation and process parameters optimization in a sequential approach for enhanced L-asparaginase production using agro-industrial wastes

A novel ternary mixture of inexpensive and nutrient-rich agro-substrates comprising groundnut de-oiled cake, corn gluten meal, and soybean meal has been explored to enhance the L-asparaginase production in solid-state fermentation. To achieve the aim, a hybrid strategy was implemented by utilizing a combination of a mixture design and artificial neural networks. The study initiated with the judicious selection of the agro-substrates based on their low C/N content in comparison to the control using the CHNS elemental analysis. The mixture composition of soybean meal (49.0%), groundnut de-oiled cake (31.5%), and corn gluten meal (19.5%) were found optimum using the simplex lattice mixture design. The agro-industrial substrates mix revealed synergistic effects on the L-asparaginase production than either of the substrates alone. The maximum L-asparaginase activity of 141.45 ± 5.24 IU/gds was observed under the physical process conditions of 70% moisture content, autoclaving period of 30 min and 6.0 pH by adopting the machine learning-derived artificial neural network (ANN) methodology. The ANN modeling showed excellent prediction ability with a low mean squared error of 0.7, a low root mean squared error of 0.84, and a high value of 0.99 for regression coefficient. Moisture content (%) was assessed to be the most sensitive process parameter in the global sensitivity analysis. The net outcome from the two sequential optimization designs is the selection of the ideal mixture composition followed by the optimum physical process parameters. The application of the enzyme demonstrated significant cytotoxicity against leukemia cell line and therefore exhibited an anti-cancer effect. The present study reports a novel mixture combination and methodology that can be used to lower the cost and enhance the production of L-asparaginase using an agro-industrial substrate mixture.

Enzyme Engineering Strategies for the Bioenhancement of L-Asparaginase Used as a Biopharmaceutical

Over the past few years, there has been a surge in the industrial production of recombinant enzymes from microorganisms due to their catalytic characteristics being highly efficient, selective, and biocompatible. L-asparaginase (L-ASNase) is an enzyme belonging to the class of amidohydrolases that catalyzes the hydrolysis of L-asparagine into L-aspartic acid and ammonia. It has been widely investigated as a biologic agent for its antineoplastic properties in treating acute lymphoblastic leukemia. The demand for L-ASNase is mainly met by the production of recombinant type II L-ASNase from Escherichia coli and Erwinia chrysanthemi. However, the presence of immunogenic proteins in L-ASNase sourced from prokaryotes has been known to result in adverse reactions in patients undergoing treatment. As a result, efforts are being made to explore strategies that can help mitigate the immunogenicity of the drug. This review gives an overview of recent biotechnological breakthroughs in enzyme engineering techniques and technologies used to improve anti-leukemic L-ASNase, taking into account the pharmacological importance of L-ASNase.

Characterization, Anti-proliferative Activity, and Bench-Scale Production of Novel pH-Stable and Thermotolerant L-Asparaginase from Bacillus licheniformis PPD37

Bacterial L-asparaginase (LA) is a chemotherapeutic drug that has remained mainstay of cancer treatment for several decades. LA has been extensively used worldwide for the treatment of acute lymphoblastic leukemia (ALL). A halotolerant bacterial strain Bacillus licheniformis sp. isolated from marine environment was used for LA production. The enzyme produced was subjected to purification and physico-chemical characterisation. Purified LA was thermotolerant and demonstrated more than 90% enzyme activity after 1 h of incubation at 80 °C. LA has also proved to be resistant against pH gradient and retained activity at pH ranging from 3.0 to 10. The enzyme also had high salinity tolerance with 90% LA activity at 10% NaCl concentration. Detergents like Triton X-100 and Tween-80 were observed to inhibit LA activity while more than 70% catalytic activity was maintained in the presence of metals. Electrophoretic analysis revealed that LA is a heterodimer (~ 63 and ~ 65 kDa) and has molecular mass of around 130 kDa in native form. The kinetic parameters of LA were tested with LA having low K_m value of 1.518 µM and V_max value of 6.94 µM/min/mL. Purified LA has also exhibited noteworthy antiproliferative activity against cancer cell lines-HeLa, SiHa, A549, and SH-SY-5Y. In addition, bench-scale LA production was conducted in a 5-L bioreactor using moringa leaves as cost-effective substrate.