Sodium ion stress accelerates cell lysis in Bacillus coagulans by exacerbating energy deficit during carbon source transition.

Sodium hydroxide induces 45% higher cell lysis in Bacillus coagulans during fermentation by causing energy deficits under carbon source transition.

• Why it matters: Choosing the appropriate pH neutralizer is crucial for optimizing fermentation efficiency and cell survival, yet the impact of sodium versus calcium hydroxide on cellular health remains unclear.
• What they did: The study compared fermentation with sodium hydroxide and calcium hydroxide, using physiology, ion experiments, and multi-omics analyses to assess phenotypic and metabolic responses in Bacillus coagulans.
• The result: Sodium hydroxide stress led to energy deficits that caused widespread cell lysis, while calcium hydroxide maintained cell stability, informing strategies for process optimization and strain engineering.