Oxidative damage of Bacillus cereus spores by atmospheric pressure plasma jet: Structural integrity and metabolic pathways

Bacillus cereus is a prevalent pathogen within the food supply chain. Through comparing spore morphology and the changes in metabolic pathways after heat and plasma treatment, this study clarified the oxidative damage process of spores caused by atmospheric pressure jet plasma (APPJ). The results showed that after APPJ treatment, spores aggregated and structure was damaged from the outside in to varying degrees, resulting in a significant reduction of approximately 60 % in resistance to heat. The rupture of the inner membrane led to the entry of active material produced by APPJ into the core, thereby oxidative damaging the macromolecular substances within the spores. Through the combined analysis of proteomics and metabolomics, it was observed that the impairment of proteins related to amino acid synthesis and energy metabolism were common responses exhibited by spores under stressful conditions. However, the disruption of signal transduction, breakdown of antioxidant systems, and impaired nucleic acid repair represented unique oxidative damage processes induced in spores by APPJ. The present study results further improved the inactivation mechanism of spores by APPJ, thereby establishing a theoretical basis for the application of plasma technology in the deactivation of bacterial spores.