摘要
Understanding how digestion-derived nutrients influence probiotic and pathogen behavior is essential for designing functional foods and microbiome-targeted formulations.This study developed a dynamic in vitro fermentation platform to quantify how milk digestion products and substrate composition regulate the growth and metabolism of Lacticaseibacillus rhamnosus GG(LGG),Bifidobacterium animalis subsp.lactis BB-12(BB-12),and Escherichia coli(E.coli).Digestates from human milk(HM),infant formula(IF),and a defined control milk(CM)were fermented under batch and semi-continuous conditions.Compared with static batch culture,semi-continuous fermentation increased probiotic viability by up to 5.8 log CFU/mL and reduced E.coli by approx-imately 1.0 log CFU/mL,demonstrating that dynamic nutrient exchange enhances ecological stability.Glucose-enriched media(CBM-G)rapidly produced lactic and acetic acids,driving competitive exclusion of E.coli,whereas lactose-based media(CBM-L)slowed acidification but sustained probiotic metabolism through gradual carbohydrate hydrolysis.The mucin-tryptone-glucose formulation(CBM-MTG)generated the most metaboli-cally diverse environment,enriched in bile acid derivatives,peptides,and flavonoid glycosides,which correlated with improved metabolic resilience.These results highlight that fermentation mode and substrate complexity synergistically determine microbial competition,metabolic pathways,and functional metabolite production.The developed platform provides an engineering framework to predict nutrient-microbe interactions and guide substrate optimization for next-generation probiotic formulations and infant nutrition research.
基金
supported by the National Natural Science Foundation of China(Grant No.22078212)
Experimental work was conducted at Pro-health(Suzhou)Instrumentation Co.,Ltd.,with additional financial support provided by the company.
