Dual role of cold plasma in suppressing the growth, remodeling cellular ultrastructure and stimulating metabolic response of Kazachstania exigua from transcriptomic insight.

This study aimed to investigate the regulating mode and underlying mechanism of cold plasma (CP) on growth, ultrastructure, and metabolic alterations of K. exigua by integrating physiological characterization, transcriptomic analysis and qRT-PCR validation. Results showed that CP delayed logarithmic phase, inhibited pectinase activity by 20.56%, and reduced flocculation by 78.46% of K. exigua. Cellular ultrastructure indicated cell wall delamination, membrane leakage, mitochondrial swelling, and nuclear damage of K. exigua by CP. Transcriptome analysis identified 2156 DEGs, which were significantly enriched in pathways of oxidative stress response, cell wall remodeling, lipid metabolism, mitochondrial function, and DNA repair. qRT-PCR analysis of representative DEGs further validated target genes of K. exigua regulated by CP included ENV9, NCP1, MET18, RAD9, GAS2, PXA1, ARE2 and COX15. CP upregulated genes associated with redox regulation and DNA repair, while downregulated flocculation, polysaccharide degradation, and cell wall biosynthesis. These results suggested CP triggered adaptive metabolic response of K. exigua by inducing multiplex stress response. This study exploited the dual role of CP for regulating growth and metabolic mode of yeasts in fermented food beyond mono-faced application for sterilization.