title: Effect of water-surface discharge on the inactivation of Bacillus subtilis due to protein lysis and DNA damage.
abstract: The effect of water-surface discharge on the inactivation of Bacillus subtilis ATCC6633 in water was examined by using a very short high-voltage pulse generator. The surviving number of spore cells at 10(4) CFU/ml in initial concentration exponentially decreased with increasing discharge-treatment time. The input energy into the water-surface discharge under an O(2) gas flow for reduction in the survival number to 10% was lower than that under an air flow because many oxidation agents such as ozone and OH radical were produced under the O(2) gas flow. The input energy density for the one-tenth reduction depended not only on the spore state but also on the initial cell concentration. The input energy for the high-concentration spore cells (10(7) CFU/ml) was much higher than that for the low-concentration spore cells (10(4) CFU/ml). Cellular proteins and DNA were degraded by a 30-min discharge treatment of vegetative cells, whereas DNA of the high-concentration spore cells was relatively resistant.
authors.affiliation: Graduate School of Science and Engineering, Department of Electrical and Electronic Engineering and Computer Science, Ehime University, 3 Bunkyo-cho, Matsuyama, Ehime 790-8577, Japan. kadowaki.kazkunori@eng.ehime-u.ac.jp
authors.forename: Kazunori
authors.initials: K
authors.lastname: Kadowaki
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Sone
authors.forename: Takashi
authors.initials: T
authors.lastname: Kamikozawa
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Takasu
authors.forename: Satoru
authors.initials: S
authors.lastname: Suzuki
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000378:metabolism*; D004249:DNA Damage; D004269:DNA, Bacterial / Q000187:drug effects*; D004203:Disinfection; D004591:Electrophoresis, Polyacrylamide Gel; D006868:Hydrolysis; D017665:Hydroxyl Radical; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D014867:Water; D017665:Hydroxyl Radical