Transcriptomic analysis of inhibitory effects of isothiazolone antimicrobial agents on Aspergillus amstelodami ZR.

The preservation of marine specimens requires effective methods to ensure research accuracy and ecological sustainability. However, conventional preservatives (e.g., formaldehyde) pose environmental and health risks due to their toxicity. In this study, we isolated Aspergillus amstelodami from the surface of Oreochromis mossambicus specimens and evaluated the antifungal potential of 1,2-benzoisothiazolin-3-one and Kathon. Both agents exhibited strong inhibitory effects on fungal growth, as evidenced by clear inhibition zones. Transcriptomic analysis revealed: (1) upregulation of detoxification-related genes, including cytochrome P450-mediated xenobiotic/drug metabolism, ABC transporters, and two-component systems, and (2) downregulation of ribosome biogenesis genes, impairing protein synthesis in Aspergillus amstelodami. In conclusion, this study provides novel insights into the molecular antifungal mechanisms of isothiazolone antimicrobial agents in combating contamination of marine biological specimens caused by Aspergillus amstelodami.