Purification and characterization of L-Amino acid oxidase from Aspergillus terreus MZ769058

L-Amino acid oxidase has significant values in different biotechnology sectors. In this study, Aspergillus terreus MZ769058 was reported as new fungal isolate for production of this enzyme. It was purified with high degree of purification fold (2.55) and high specific activity (132.5 U/mg protein). Electrophoresis confirmed its homodimer nature with molecular weight of whole enzyme as 180 kDa and its subunit as 90 kDa. This enzyme showed maximum activity of 193.5 U/l at optimum value of pH 6.0. The enzyme was active throughout a wide range of temperatures and showed maximum activity (227.08 U/l) at optimum temperature 30 °C. The value of Michaelis parameters of K_m and V_max was estimated as 26 mM and 250 µmole/min/mg proteins, respectively. The catalytic efficiency of this enzyme (K_cat) value was determined as 2.5 µmole/min/mg. Metal salts like FeSO₄ (85.4%), Na₂MO₄ (81.2%), and CuSO₄ had showed negative effect on its activity. This enzyme was strongly inhibited with α-napthol (34.4%), EDTA (34.2%), Glycine (39%) sodium azide (41.4%), and riboflavin (85.3%). Fourier transform infrared spectroscopy had confirmed the presence of the amine and aldehyde groups with C-H stretch, C = O stretch, C–O stretch at peak of 2927.95, 1745.25, and 1078.64 cm⁻¹. This enzyme showed greater zone of inhibition against growth of Bacillus subtillis ATCC 11774 (6 ± 0.14) and Staphylococcus aureus ATCC 25923 (12.00 ± 0.12). This enzyme could be used for effective therapeutic agent in biotechnological sector.