Fuente: PubMed "apiculture" Sci Rep. 2026 Jul 4. doi: 10.1038/s41598-026-58906-z. Online ahead of print.ABSTRACTPaenibacillus larvae, the causative agent of American foulbrood, poses a major threat to global apiculture. This study evaluated the antibacterial efficacy of plasma-activated water generated using air (PAW-Air) or argon (PAW-Argon) against vegetative P. larvae. PAW-Air contained higher concentrations of nitrate (NO₃⁻; 100-1,000 mg/L) and nitrite (NO₂⁻; 50-600 mg/L), whereas PAW-Argon contained higher concentrations of hydrogen peroxide (H₂O₂; 30-150 mg/L). Despite these physicochemical differences, both PAW-Air and PAW-Argon significantly reduced viable cell counts. Viable counts ranged from 4.65 to 4.74 log CFU/mL following PAW-Air treatment and from 4.54 to 4.67 log CFU/mL following PAW-Argon treatment. PAW exposure increased membrane-compromised cells and reduced relative membrane integrity to 35.87-37.47%, accompanied by enhanced leakage of intracellular nucleic acids and proteins, and severe morphological damage. Among representative long-lived reactive species, H₂O₂ exhibited dose-dependent antibacterial effects, whereas NO₃⁻ and NO₂⁻ showed comparatively weaker effects. In a honeybee larval infection model, larvae fed PAW-treated bacteria showed significantly reduced bacterial loads, with no detectable colonies in the PAW-Air groups and only 1.11 ± 0.67 CFU/larva in the PAW-Argon group. Larval survival was also improved in PAW-treated groups (59.38-60.42%) compared with untreated infection controls (43.23%). These findings suggest that PAW can reduce the culturability and infectivity of vegetative P. larvae, likely through oxidative membrane-associated damage, and provide a basis for further investigation of plasma-based strategies for American foulbrood control.PMID:42401629 | DOI:10.1038/s41598-026-58906-z