SONG Shuxia, ZHU Yue, REN Guangyue, YOU Xiaoyan
Akkermansia muciniphila (Akk), a potential probiotic within the gut microbiota, plays a role in regulating mucus layer homeostasis and host metabolism.However, its strain safety and probiotic efficacy require systematic evaluation for food-based applications.This study comprehensively assessed the probiotic properties of Akk ATCC BAA835 through in vitro assays, including adhesion (biofilm formation, self-aggregation, hydrophobicity), antioxidant activity (DPPH free radical/hydroxyl radical/superoxide anion scavenging), acid/bile salt tolerance, and gastrointestinal survival simulation.Additionally, antibiotic susceptibility tests and acute/subacute toxicity animal trials were conducted to evaluate safety.Key findings revealed that Akk ATCC BAA835 did not form biofilms, exhibited a self-aggregation rate of 37.97% (24 h, moderate), and displayed hydrophobicity exceeding 50% in xylene, hexadecane, and octane solutions (up to 70.42% in xylene at 8 h).The strain fermentation broth demonstrated superior scavenging capacity for DPPH free radical and superoxide anions compared to bacterial suspensions and cell-free supernatants.Survival rates exceeded 88% under pH 2.0 and 3 mg/mL bile salt conditions, with >95% viability in simulated gastrointestinal fluids, indicating robust environmental tolerance.Antibiotic susceptibility testing showed resistance to aminoglycosides.Acute toxicity tests at 1×1011 CFU/kg body weight caused no mortality or organ damage in animals, while serum total cholesterol levels significantly decreased versus controls.In subacute toxicity trials, high-dose females (1×1010 CFU/kg/d) exhibited slightly elevated kidney organ coefficients, though histopathological analysis (H&E staining) revealed no abnormalities.Notably, red blood cell distribution width values declined significantly, suggesting improved erythrocyte physiology.This systematic evaluation of Akk ATCC BAA835’s probiotic traits and safety provides critical data to support its development as a functional probiotic and offers reference for future applications in functional foods.