接种量对单增李斯特菌生长期及生长界面的影响
Effect of inoculum size on growth phase and growth interface of Listeria monocytogenes under different cultural conditions
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摘要: 为了初步了解接种量对单增李斯特菌生长状况及生长/非生长界面的影响,本实验对单增李斯特菌在0、4、10、25℃下通过培养菌液在600nm下的吸光光度值对其生长周期曲线分别进行了测定,并分析了不同接种量的单增李斯特菌菌液在25℃下的生长周期状况,探讨了纯培养条件下不同盐度和pH下,接种量对单增李斯特菌生长/非生长状况的影响。结果表明:不同的温度下,单增李斯特菌的生长周期有很大的差别;而在相同温度下,接种量对单增李斯特菌的生长周期有较大的影响,随着接种水平的降低,菌种生长所需的延滞时间越长,接种量为107CFU/mL时,其生长延滞期为0~4h,而当接种量减少为10CFU/mL时,其生长延滞期为0~16h;而对于单增李斯特菌的生长/非生长界面而言,接种量对其也有一定的影响,但其作用机制还有待进一步深入的研究。Abstract: To preliminary understanding the influence of inoculation level on growth/no growth interface of Listeria monocytogenes, the experiment was carried on 0, 4, 10, 25℃ under 600 nm absorption values to determine its growth phase by its turbidity of bacteria liquid respectively, and the growth state of Listeria monocytogenes in different inoculum size under 25℃ was analyzed, and the effect of inoculation level on growth/no growth interface of Listeria monocytogenes under pure cultivation combined with different salinity and pH was discussed.The results showed that there was a big difference among the growth of Listeria monocytogenes under different temperatures. And at the same temperature, inoculation level had a great influence on the growth of Listeria monocytogenes. With the decrease of inoculation level, the lag phase required for bacterial growth was prolonged. When the inoculation level was 107CFU/mL, its lag phase was 0 ~4h. However, its lag phase increased to 0~16h when the inoculation level reduced to 10CFU/mL In terms of growth/no growth of Listeria monocytogenes, inoculum size also had certain influence on its interface, but the mechanism requires further specific studies.