摘要
Clostridium perfringens is a common spore-forming pathogen in meat products.This study investigated the effect of different heat treatments on the germination and inactivation of C.perfringens spores and its mechanism.The results showed that the germination and inactivation behaviors of C.perfringens spores mainly depended on the heating temperature,and prolonging the treatment time increased its extent.Over 97%of C.perfringens spores germinated after heating at 80℃ for 40 min,as reflected by the amount of the spore inactivation and colony forming efficiency.It was found that the up-regulation of cspA,cspC and sleC genes expression of the spores may promote the synthesis of SleC,a cortex hydrolase,thereby enhancing cortex hydrolysis.These results were also supported by the increase of cortex fragments,pyridine-2,6-dicarboxylic acid release and adenosine triphosphate synthesis of the spores.Fluorescence photomicrographs also revealed that cortex hydrolysis of the spore was promoted,accompanied by significantly increase in the fluorescence intensity of SYTO 9 green nucleic acid stains.When treated at 100℃,most of C.perfringens spores became inactivated.This may be attributed to the disruption of their inner membrane and cortex,as shown by the increase in propidium iodide fluorescence and cortex fragments of the spores.This study elucidated the dual roles of different heat treatments on C.perfringens spores,providing more evidence for their germination and inactivation in meat processing.
基金
supported by the National Key R&D Program of China[grant no.2023YFF1103900]
the Key Science&Technology Project of Anhui Province[grant no.202423l10050057]
the Fundamental Research Funds for the Central Universities of China[grant no.JZ2024HGPB0264 and JZ2023HGQA0111].
