Comparison of Yeast Inactivation Treated in He,Air and N_2 DBD Plasma  

作　　者：金英 任春生 修志龙 王德真 王友年 于红 

机构地区：[1]State Key Laboratory of Material Modification by Electron, Ion and Laser Beams,Dalian University of Technology, Dalian 116023, China

出　　处：《Plasma Science and Technology》2006年第6期720-723,共4页等离子体科学和技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant No.10275010)

摘　　要：In this paper, the mechanism of yeast inactivation in low temperature atmospheric pressure helium, nitrogen and air plasmas generated by dielectric barrier discharge is analysed and compared. The results show that all the three gas plasmas have a high germicidal efficiency. The morphology of the yeast is observed by scanning electron microscopy, which reveals that the yeast treated in helium plasma is ruptured completely but there are only some flaws on the cell walls in the nitrogen and air plasma treated samples. Also, the flaws on the cell walls treated by air plasma are more significant than that by nitrogen treatment. Simultaneously, the pH values of the samples after 5 rain nitrogen and air plasma treatment have no remarkable change either, while the sample treated with helium plasma descends below 4.0, which is beyond the optimum one for the yeast＇s living environment. The difference in pH values may be caused by the treatment effect and the degree of the cell＇s rupture when the gas discharge plasma treatment is applied.In this paper, the mechanism of yeast inactivation in low temperature atmospheric pressure helium, nitrogen and air plasmas generated by dielectric barrier discharge is analysed and compared. The results show that all the three gas plasmas have a high germicidal efficiency. The morphology of the yeast is observed by scanning electron microscopy, which reveals that the yeast treated in helium plasma is ruptured completely but there are only some flaws on the cell walls in the nitrogen and air plasma treated samples. Also, the flaws on the cell walls treated by air plasma are more significant than that by nitrogen treatment. Simultaneously, the pH values of the samples after 5 rain nitrogen and air plasma treatment have no remarkable change either, while the sample treated with helium plasma descends below 4.0, which is beyond the optimum one for the yeast＇s living environment. The difference in pH values may be caused by the treatment effect and the degree of the cell＇s rupture when the gas discharge plasma treatment is applied.

关 键 词：dielectric barrier discharge YEAST INACTIVATION electrostatic tension pH 

分 类 号：O53[理学—等离子体物理]