Abstract

Endophytic fungi have emerged as valuable reservoirs for discovering bioactive compounds with significant biological properties. In this study, a novel endophytic fungus, Talaromyces pinophilus 47 K9, was isolated from Prosopis stephaniana. The antimicrobial enzyme glucose oxidase was purified from the culture medium of T. pinophilus 47 K9 through a series of techniques, including 70 % ammonium sulfate precipitation, solid-phase extraction, ultrafiltration, ion-exchange chromatography, and gel filtration. The enzyme was identified using SDS-PAGE and proteomic analysis via MS/MS sequencing. Biochemical characterization revealed a molecular weight of 65.8 kDa and an enzymatic activity of 0.71 U/mL when glucose served as a substrate. The glucose oxidase demonstrated broad stability within a pH range of 3 to 10, though it was thermally unstable at temperatures exceeding 60 °C. Substrate specificity tests indicated that glucose served as the optimal substrate for H₂O₂ production, which subsequently improved antimicrobial efficacy. Notably, the glucose oxidase exhibited broad-spectrum antimicrobial activity, effectively inhibiting five Candida species, six phytopathogenic fungi, and both Gram-positive and Gram-negative bacteria. Given its potent antimicrobial properties, high substrate specificity, and stability across diverse conditions, glucose oxidase from T. pinophilus 47 K9 holds potential as a viable alternative antimicrobial agent.