L-asparaginase by filamentous fungi and yeasts from lichens and soils across maritime Antarctic islands

This study aimed to evaluate L-asparaginase (L-ASNase) production by fungi isolated from soils across different Antarctic islands. Out of 138 isolates, 33 filamentous fungi and 5 yeasts exhibited enzymatic activity in solid culture media. Filamentous fungi were identified by sequencing the Internal Transcribed Spacer (ITS) region, while yeasts were identified using the D1/D2 domains of the 26 S rDNA gene. The blue filamentous fungus Antarctomyces F13.CR.LASP exhibited a maximum L-ASNase productivity of 0.76 U/L. Regarding the yeasts, the isolate Vishniacozyma victoriae G.L11 reached a productivity of 0.17 U/L, while corresponding values for glutaminase and urease were 0.11 and 0.06 U/L, respectively. Furthermore, V. victoriae G.L11 was capable of producing the enzyme using different low-cost substrates, particularly pineapple peel waste, which yielded 5.17 U/L. In this scenario, future optimization could further enhance L-asparaginase production levels by these fungi, providing valuable insights into the biotechnological potential of Antarctic fungi.