The spores of bacillus subtilin were treated with the non-thermal plasma induced by the dielectric barrier discharge

and were observed with electron scanning microscope. It was shown that outer structure of spores was destroyed and the inclusion of spores was dissolved after the treatment of the discharge plasma. Two basic mechanisms are involved in the air plasma inactivation bacterium spores

i.e.

one is high-velocity species from air plasma knocked through the outer structure of bacterium spores; another is erosion of the surface structure of bacterium spores by high-energy radicals from air plasma.