A comparison of solid and liquid media for resuscitation of starvation- and low-temperature-induced nonculturable cells of Aeromonas hydrophila

Like many other gram-negative bacteria, starved cells of Aeromonas hydrophi la can be induced into a viable but nonculturable (VBNC) state by incubatio n at low temperature, as shown here by using various bacterial enumeration methods. Starved A. hydrophila strain HR7 cells at 4 degreesC reached the n onculturable stage in about 45 days. The cells were resuscitated by either a solid medium resuscitation method, using solid agar amended with H2O2-deg rading agents, catalase or sodium pyruvate, or a liquid medium resuscitatio n method, by incubating nonculturable cells in liquid media containing thes e compounds before spreading onto plates. The liquid medium resuscitation m ethod using catalase resulted in nearly complete recovery of nonculturable cells.