Relationship between membrane damage, leakage of intracellular compounds, and inactivation of Escherichia coli treated by pressurized CO2.

The relationship between membrane damage, leakage of intracellular compounds, and inactivation of Escherichia coli treated by pressurized CO2 was investigated by assessing the inactivation, bacterial cell membrane permeability, the leakage of protein, nucleic acid, and K(+) and Mg(2+) of E. coli. The results indicated that pressurized CO2 treatment induced the leakage of protein in E. coli, but the time of leakage was lagged behind the time of 99% E. coli inactivation, so it was only the secondary phenomenon of inactivation. The inactivation of E. coli was related to the leakage of nucleic acid, K(+) , Mg(2+) induced by the pressurized CO2 treatment. There was direct relationship between the inactivation of E. coli and the damaging effect of pressurized CO2 treatment on the cell membrane of E. coli.