Abstract:

In order to explore the resuscitative capability of viable but nonculturable (VBNC) Escherichia coli O157:H7,
the bacteria were induced into LB broth and physiological saline at low temperatures (－18 ℃) respectively. Plate count,
scanning electron microscope and qPCR technique were used to detect the VBNC cell populations on the 15th and 18th days,
respectively. Resuscitation of VBNC samples within 2 d was achieved by direct heating to 37 ℃, addition of 25% yeast
extract at 25 ℃, or addition of 8% Tween-80 at 37 ℃. The pattern of the resuscitated VBNC cells was similar to that of the
normal cells. However, the bacteria could not resuscitate after the VBNC state was kept for 15 d.

Key words: VBNC state, E. coli O157:H7, resuscitation, detection