15:00 〜 15:15
▲ [16p-2V-5] Effect of Dielectric Barrier Discharge on Spore Common in Buckwheat Powder
キーワード: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.