Abstract: In response to nutrient limitation, Bacillus and Clostridium can form metabolically dormant spores, which are extremely resistant to a variety of environmental stresses. The ubiquitousness of spores in the environment makes it inevitable for them to enter the food processing chain. Once suitable conditions are available, spores will rapidly germinate to resume vegetative growth, thereby causing food spoilage. Since germination induces the loss of stress resistance in dormant spores, germination-inactivation strategy has been developed to mildly kill spores while maintaining food quality. Understanding the spore germination process of diverse bacterial species, the related signal transduction mechanism and the factors impacting the germination process are beneficial to develop efficient and precise strategies for inducing spore germination and raising the efficiency of inactivation, which is of great significance to the control of spores in foods. This review describes the mechanisms of the spore germination of Bacillus subtilis, Clostridium perfringens and C. difficile in terms of spore germination receptor activation and signal transduction. Moreover, inducers and inhibitors of spore germination of diverse bacterial species are also comprehensively summarized. This review provides a theoretical foundation for effectively controlling bacterial spores in foods and ensuring food quality.

Key words: Bacillus spores; Clostridium spores; germination mechanism; germinant; germination receptors; signal transduction