Inactivation characteristics of Bacillus thuringiensis spore in liquid using atmospheric torch plasma using oxygen

The atmospheric plasma torch produced by a barrier discharge using air and oxygen as working gases is adopted to inactivate microorganisms in a liquid. The inactivation characteristics of bacillus spore are investigated and compared with the heat sterilization method, and sterilization factors are active species with short-lifetimes produced in water. The population of Bacillus thuringiensis spore in pure water decreases 10−3 times within 20 min, and the obtained result is equivalent to the heat sterilization of 95 °C.

► Plasma irradiation effect is equivalent to the heat inactivation with 95 °C.
► Survival curve with the plasma treatment are similar to that with heat treatment.
► Inactivation mechanism by the plasma would be decomposition of cell wall proteins.