TY - GEN AB - The Bacillus cereus group represents a serious risk in powdered and amylaceous foodstuffs. Cold plasma (the fourth state of matter) is emerging as an alternative effective nonthermal technology for pasteurizing a wide range of matrices in solid, liquid, and powder form. The present study aims to evaluate the mechanisms involved in Bacillus cereus inactivation via cold plasma, focusing on (i) the technology’s ability to generate damage in cells (at the morphological and molecular levels) and (ii) studying the effectiveness of cold plasma in biofilm mitigation through the direct effect and inhibition of the biofilm-forming capacity of sublethally damaged cells post-treatment. Dielectric barrier discharge cold plasma (DBD-CP) technology was used to inactivate B. cereus, B. thuringiensis, and B. mycoides under plasma power settings of 100, 200, and 300 W and treatment times ranging from 1 to 10 min. Inactivation levels were achieved in 2–7 log10 cycles under the studied conditions. Percentages of sublethally damaged cells were observed in a range of 45–98%, specifically at treatment times below 7 min. The sublethally damaged cells showed poration, erosion, and loss of integrity at the superficial level. At the molecular level, proteins and DNA leakage were also observed for B. cereus but were minimal for B. mycoides. Biofilms formed by B. cereus were progressively disintegrated under the DBD-CP treatment. The greater the CP treatment intensity, the greater the tearing of the bacteria’s biofilm network. Additionally, cells sublethally damaged by DBD-CP were evaluated in terms of their biofilm-forming capacity. Significant losses in the damaged cells’ biofilm network density and aggregation capacity were observed when B. cereus was recovered after inactivation at 300 W for 7.5 min, compared with the untreated cells. These results provide new insights into the future of tailored DBD-CP design conditions for both the inactivation and biofilm reduction capacity of B. cereus sensu lato species, demonstrating the effectiveness of cold plasma and the risks associated with sublethal damage generation. AD - Universitat de València, Valencia, Spain AD - School of Engineering, HES-SO Valais-Wallis, HEI, HES-SO University of Applied Sciences and Arts Western Switzerland AD - Departamento de Conservación y Calidad de los Alimentos, IATA-CSIC, Paterna, Spain AD - Departamento Tecnología de Alimentos, Instituto Universitario de Ingeniería de Alimentos-FoodUPV, Valencia, Spain AD - Universitat de València, Valencia, Spain AD - Universitat de València, Valencia, Spain AU - Eced-Rodríguez, Laura AU - Beyrer, Michael AU - Rodrigo, Dolores AU - Rivas, Alejandro AU - Esteve, Consuelo AU - Consuelo Pina-Pérez, Maria CY - Basel, Switzerland DA - 2024-10 DO - 10.3390/foods13203251 DO - DOI EP - 3251 ID - 15258 JF - Foods KW - sublethal damage KW - cold plasma KW - bacillus cereus KW - viability KW - biofilm KW - food safety KW - powder products L1 - https://arodes.hes-so.ch/record/15258/files/Beyrer_2024_sublethal_damage_caused_cold_plasma_bacillus_cereus_cells.pdf L2 - https://arodes.hes-so.ch/record/15258/files/Beyrer_2024_sublethal_damage_caused_cold_plasma_bacillus_cereus_cells.pdf L4 - https://arodes.hes-so.ch/record/15258/files/Beyrer_2024_sublethal_damage_caused_cold_plasma_bacillus_cereus_cells.pdf LA - eng LK - https://arodes.hes-so.ch/record/15258/files/Beyrer_2024_sublethal_damage_caused_cold_plasma_bacillus_cereus_cells.pdf N2 - The Bacillus cereus group represents a serious risk in powdered and amylaceous foodstuffs. Cold plasma (the fourth state of matter) is emerging as an alternative effective nonthermal technology for pasteurizing a wide range of matrices in solid, liquid, and powder form. The present study aims to evaluate the mechanisms involved in Bacillus cereus inactivation via cold plasma, focusing on (i) the technology’s ability to generate damage in cells (at the morphological and molecular levels) and (ii) studying the effectiveness of cold plasma in biofilm mitigation through the direct effect and inhibition of the biofilm-forming capacity of sublethally damaged cells post-treatment. Dielectric barrier discharge cold plasma (DBD-CP) technology was used to inactivate B. cereus, B. thuringiensis, and B. mycoides under plasma power settings of 100, 200, and 300 W and treatment times ranging from 1 to 10 min. Inactivation levels were achieved in 2–7 log10 cycles under the studied conditions. Percentages of sublethally damaged cells were observed in a range of 45–98%, specifically at treatment times below 7 min. The sublethally damaged cells showed poration, erosion, and loss of integrity at the superficial level. At the molecular level, proteins and DNA leakage were also observed for B. cereus but were minimal for B. mycoides. Biofilms formed by B. cereus were progressively disintegrated under the DBD-CP treatment. The greater the CP treatment intensity, the greater the tearing of the bacteria’s biofilm network. Additionally, cells sublethally damaged by DBD-CP were evaluated in terms of their biofilm-forming capacity. Significant losses in the damaged cells’ biofilm network density and aggregation capacity were observed when B. cereus was recovered after inactivation at 300 W for 7.5 min, compared with the untreated cells. These results provide new insights into the future of tailored DBD-CP design conditions for both the inactivation and biofilm reduction capacity of B. cereus sensu lato species, demonstrating the effectiveness of cold plasma and the risks associated with sublethal damage generation. PB - MDPI PP - Basel, Switzerland PY - 2024-10 SN - 2304-8158 SP - 3251 T1 - Sublethal damage caused by cold plasma on bacillus cereus cells :impact on cell viability and biofilm-forming capacity TI - Sublethal damage caused by cold plasma on bacillus cereus cells :impact on cell viability and biofilm-forming capacity UR - https://arodes.hes-so.ch/record/15258/files/Beyrer_2024_sublethal_damage_caused_cold_plasma_bacillus_cereus_cells.pdf VL - 2024, 13 Y1 - 2024-10 ER -