Summary: | 碩士 === 東吳大學 === 微生物學系 === 88 === Vibrio parahaemolyticus is one of the most important foodborne pathogens in Taiwan. Bacteria can survive well in environment in a viable but non-culturable state (VNC), wherein the viable cells are no longer culturable on routine plating media but can be shown to remain viable. The aims of this investigation are on the formation and resuscitation of VNC state in V. parahaemolyticus. In this study, logarithmic-phase-grown cells of the estuarine bacterium V. parahaemolyticus ST550 became nonculturable in nutrient-limited modified Morita mineral salts solution (MMS) microcosms after 28-35 days at 4℃. When the nonculturable cells were subjected to temperature upshift by being placed at room temperature , resuscitation occured at the original bacterial numbers were detectable by plate counts after 3 days. Without the addition of nutrient suggested that temperature is be the determing factor in the resuscitation from the VNC state. About two weeks after into the VNC state, no cell can be recover. There are more tolerant to heating, sanility and acid treatment while VNC state . Different strains could reach the VNC stage between 28 to 49 days . Clinical Kanagawa positive strains lost culturability at low temperature.
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