单增李斯特菌非可培养状态的诱导与PMA-qPCR检测

Induction and PMA-qPCR detection of Listeria monocytogenes in viable but non-culturable state

摘要: 在9%（w/v）NaCl条件下,通过温度、pH两种因素诱导一株单增李斯特菌进入"活的非可培养"（viable but non-cuturable,VBNC）状态。通过LIVE/DEAD Baclight活菌检测试剂盒检测细菌总数与活菌数,比较单增李斯特菌状态及数量的差异与变化。结果显示,在2℃、pH6.0条件下单增李斯特菌活菌全部进入VBNC状态。用PMA-qPCR对经诱导的四份菌液进行检测,结果表明该方法能快速、准确地测出死菌背景下的活的单增李斯特菌。

Abstract: Under the condition of 9% ( w /v) NaCl, the induction of “viable but non culturable” ( VBNC) Listeria monocytogenes was undertaken by investigating two factors, temperature and pH. In order to compare the changes of bacteria state and numbers caused by different inducing conditions, the LIVE/DEAD  BacLightTM Bacterial Viability Kit was used for enumeration of total cells and viable cells. The results showed that all viable Listeria monocytogenes were induced into the VBNC state at 2℃, pH6.0.PMA- qPCR was proposed to detect the Listeria monocytogenes experienced different inductions.It was indicated that PMA-qPCR was an effective method to detect viable Listeria monocytogenes even if undering the dead cells background.