In this study,with Lactobacillus rhamnosus GG (LGG) as control strain,probiotic probiotic Lactobacillus plantarum BF_15,isolated from breast milk infant,was used as the research object to evaluate its antioxidant activity in vitro,safety and alleviation of the DSS-induced oxidative damage in the colon of mice.The results show that the test strain Lactobacillus plantarum BF_15 could tolerate high concentrations of H2O₂ (3.5 mmol/L).In the fermentation supernatant,the scavenging ability of strain BF_15 on DPPH was lower than that of the control strain LGG (P＜0.01);the scavenging ability of oOH was higher than LGG (P＜0.05);the scavenging ability of ·O₂- was higher than LGG (P＞0.05);anti-lipid peroxidation ability was lower than LGG (P<0.01).In the bacterial suspension,the scavenging ability of strain BF_15 on DPPH and ·O₂- was higher than that of the control strain LGG (P>0.05);the scavenging ability on ·OH was higher than LGG (P＜0.01);the anti-lipid peroxidation ability was lower than LGG (P<0.01).Meanwhile,Neither the test strain BF_15 nor the control strain LGG produced harmful metabolites (bioamine,nitrite,indole),and had hemolytic properties.In animal experiments,the strain BF_15 could reduce the degree of intestinal mucosal damage and inflammatory cell infiltration,increase the activity of superoxide dismutase (SOD) (P<0.01),and reduce the level of malondialdehyde (MDA) content (P<0.01) through early intragastric administration,which effectively alleviated the symptoms of DSS-induced oxidative damage in the colon of mice;its effect was equivalent to that of the control strain LGG (P>0.05).This study provided a scientific basis for the development and application of probiotics derived from human breast milk infants and their early intervention to relieve intestinal diseases such as ulcerative colitis(UC).This study laid a solid foundation for probiotics in the prevention of intestinal diseases such as ulcerative colitis (UC),and provided a reference guide for oxidative stress as a new therapeutic target.