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bioRxiv · 10.1101/2020.02.04.934851

Lactobacillus curvatus Strains Specifically Show High Levels of Tolerance to Freeze-Thaw Stress

Ikai, R.·Tanabe, K.·Shima, J.
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Abstract

Tolerance to freeze-thaw stress is an important characteristic in recent fermentation processes. To gain insight into the freeze-thaw tolerance of lactic acid bacteria (LAB), we performed screening experiments and observed that several Lactobacillus curvatus strains showed high freeze-tolerance even in the absence of cryoprotectants. These Lb. curvatus strains also showed high levels of freeze tolerance in a milk fermentation process. Lactobacillus sakei (closely related to Lb. curvatus) was not revealed to be a freeze-thaw tolerant strain. These data indicate that Lb. curvatus has specific mechanisms underlying its tolerance to freeze-thaw stress. ImportanceOur findings demonstrate that Lb. curvatus strains frequently show high levels of freeze-thaw tolerance in both culture and milk and that Lb. curvatus strains are suitable as a model species for investigations of the molecular mechanisms underlying freeze-thaw tolerance in LAB and for applications in fermentation industries.

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Ikai, R., Tanabe, K., Shima, J.. 2020-02-05. Lactobacillus curvatus Strains Specifically Show High Levels of Tolerance to Freeze-Thaw Stress. https://doi.org/10.1101/2020.02.04.934851

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