EFFECT OF HOMOGENEOUS AND INHOMOGENEOUS HIGH MAGNETIC-FIELDS ON THE GROWTH OF ESCHERICHIA-COLI

The growth of Escherichia coli B was investigated under homogeneous 7 Tesla (T) magnetic field, and inhomogeneous 5.2 similar to 6.1 T and 3 .2 similar to 6.7 T magnetic fields which are produced by a newly cons tructed superconducting magnet biosystem (SBS). These high magnetic fi elds adversely affected on the growth of the bacterium in the early lo garithmic growth phase. However, in the stationary phase, the cell num ber under a high magnetic held was about 2 similar to 3 times higher t han that of a control, indicating that the magnitude of the decrease i n the cell number was reduced by the high magnetic held. The effect of the inhomogeneous magnetic field was much stronger than that of the h omogeneous one. The high magnetic field was found to affect the cells of the bacterium differently, depending on the growth phases.