植物乳杆菌9-4的分离鉴定及其对小鼠结肠炎缓解作用的研究OA

To develop probiotic products capable of regulating oxidative stress and alleviating intestinal inflammation in animals,Lactobacil⁃lus plantarum strain 9-4 was isolated and screened from fresh wild boar feces through in vitro antioxidant tests.Antibacterial activity of the strain was detected via the Oxford cup method,and its tolerance to artificial gastrointestinal fluids and bile salts was evaluated.Then,a mouse colitis model was established using 3％dextran sulfate sodium(DSS),and the effects of L.plantarum 9-4 intervention on clinical symptoms,intestinal inflammation,and serum oxidative stress levels in colitis mice were analyzed.The results were as follows:L.plantarum 9-4 exhibited inhibitory effects on Escherichia coli,Salmonella,and Staphylococcus aureus,and maintained a high survival rate in artificial gastric juice,artificial intestinal fluid,and 0.3％bile salt.Intervention with L.plantarum 9-4 significantly increased the body weight of the colitis mice(P<0.001),reduced the disease activity index(DAI)(P<0.001)in the rodents,and attenuated their colon length shortening(P<0.05).Additionally,L.plantarum 9-4 intervention significantly decreased the serum malondialdehyde(MDA)levels in the mice(P<0.01),while the superoxide dismutase(SOD),catalase(CAT),and glutathione peroxidase(GSH-Px)levels in them showed an upward trend.Moreover,the mRNA expression levels of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),and interleukin-6(IL-6)in the colon tissue of the mice were significantly downregulated(P<0.05).In conclusion,L.plantarum 9-4 possessed antioxidant and anti- inflammatory effects and promised a potential to be developed into probiotic preparation for use in livestock and poultry farming.