[16p-2V-1~11] 8.6 Plasma life sciences

▲ [16p-2V-5] Effect of Dielectric Barrier Discharge on Spore Common in Buckwheat Powder

〇(D)Mohammad Pervez¹, Takanori Inomata¹, Tatsuo Ishijima¹, Makiko Kakikawa¹, Yasunori Tanaka¹, Yohishiko Uesugi¹, Toshihiro Yano², Shoji Miwa³, Akinori Noguchi⁴ (1.Kanazawa Univ., 2.Kanazawa Gakuin Junior College, 3.Ishikawa Agriculture Forestry Research Center, 4.Sodick Co., Ltd.)

Keywords:Plasma spore surface interaction,Pulsed Electric field,Inactivation

Bacillus lichenformis is a common spore found in buckwheat seeds and powder which contains ~ 10⁴ spores per g. In this study spores were spread on glass slide and placed in the treatment chamber to investigate direct DBD treatment effect. Spores in the chamber are exposed to various reactive species produced by DBD and the periodic variation of the electric field in discharge chamber which synergistically inactivate microorganism . Helium is used as main feed gas for DBD and small amount of O₂ is added in the feed gas flow to enhance reactive oxygen species production. Spores on glass slide are treated in the DBD chamber for different time duration while O₂ concentration in the feed gas flow is varied. Treated spores were examined by field emission scanning electron microscope (FE-SEM) to observe the spore surface. Influence of addition of O₂ in the feed gas is investigated by measuring inactivation efficiency.Increasing the O₂ concentration from 0.5% to 1%, increases inactivation efficiency but increasing O₂ concentration to 2% reduces inactivation effect.