TY - JOUR
T1 - The role of humidity and UV-C emission in the inactivation of B. subtilis spores during atmospheric-pressure dielectric barrier discharge treatment
AU - Kogelheide, Friederike
AU - Voigt, Farina
AU - Hillebrand, Bastian
AU - Moeller, Ralf
AU - Fuchs, Felix
AU - Gibson, Andrew R.
AU - Awakowicz, Peter
AU - Stapelmann, Katharina
AU - Fiebrandt, Marcel
N1 - Publisher Copyright:
© 2020 The Author(s). Published by IOP Publishing Ltd.
PY - 2020/5/19
Y1 - 2020/5/19
N2 - Experiments are performed to assess the inactivation of Bacillus subtilis spores using a non-thermal atmospheric-pressure dielectric barrier discharge. The plasma source used in this study is mounted inside a vacuum vessel and operated in controlled gas mixtures. In this context, spore inactivation is measured under varying nitrogen/oxygen and humidity content and compared to spore inactivation using ambient air. Operating the dielectric barrier discharge in a sealed vessel offers the ability to distinguish between possible spore inactivation mechanisms since different process gas mixtures lead to the formation of distinct reactive species. The UV irradiance and the ozone density within the plasma volume are determined applying spectroscopic diagnostics with neither found to fully correlate with spore inactivation. It is found that spore inactivation is most strongly correlated with the humidity content in the feed gas, implying that reactive species formed, either directly or indirectly, from water molecules are strong mediators of spore inactivation.
AB - Experiments are performed to assess the inactivation of Bacillus subtilis spores using a non-thermal atmospheric-pressure dielectric barrier discharge. The plasma source used in this study is mounted inside a vacuum vessel and operated in controlled gas mixtures. In this context, spore inactivation is measured under varying nitrogen/oxygen and humidity content and compared to spore inactivation using ambient air. Operating the dielectric barrier discharge in a sealed vessel offers the ability to distinguish between possible spore inactivation mechanisms since different process gas mixtures lead to the formation of distinct reactive species. The UV irradiance and the ozone density within the plasma volume are determined applying spectroscopic diagnostics with neither found to fully correlate with spore inactivation. It is found that spore inactivation is most strongly correlated with the humidity content in the feed gas, implying that reactive species formed, either directly or indirectly, from water molecules are strong mediators of spore inactivation.
KW - atmospheric pressure
KW - Bacillus subtilis spores
KW - controlled atmosphere
KW - dielectric barrier discharge
KW - inactivation experiments
KW - spectroscopy
UR - http://www.scopus.com/inward/record.url?scp=85085611271&partnerID=8YFLogxK
U2 - 10.1088/1361-6463/ab77cc
DO - 10.1088/1361-6463/ab77cc
M3 - Article
AN - SCOPUS:85085611271
SN - 0022-3727
VL - 53
JO - Journal of Physics D: Applied Physics
JF - Journal of Physics D: Applied Physics
IS - 29
M1 - 295201
ER -