Mass spectrometric study on inactivation mechanism of spore-forming bacteria by low-pressure surface-wave excited oxygen plasma

In this letter, the etching phenomena of the spore-forming bacteria by oxygen plasma were investigated by using quadrupole mass spectrometry. The etching by-products of H(2)O and CO(2) were obviously detected during the oxygen plasma irradiation by the multiple ion detection measurement. Inactivation of roughly 10(6) spores population was achieved under almost the same reduced spore shapes for three different incident microwave powers. It is considered from the present results that the oxygen radical etching could cause damage to the germinant receptors located in the inner membrane inevitable for germination of spores, without any damage of the DNA in the cores. (C) 2011 American Institute of Physics. [doi:10.1063/1.3588036]