Abstract
Cell suspellsion (108.5±0.1 colony-fbrming units/ml) was maintained tightly in an aluminum container and exposed to shock pressures generated by hitting the alulninum container with a projectile. In the presence of sodium ascorbate, a potent radical scavenger, the drastic reduction in the number of colony-fbrming cells was observed at a projectile velocity of more than 196m/s, for which the estimated maximum value of shock pressures was 421 MPa. In the absence of sodium ascorbate, however, colnplete killing of the cells has been obtained even at 115m/s. Burst of the cell wall was seen after exposure to shock pressures at 267m/s, regardless of the presence of sodium ascorbate. These results strongly indicate that shock pressures with the complete killing effect on the cells have a potential to generate radlcal species in seawater as well as inflict some structural damage to the cell wall.
