| R.roxburghii is a key medicinal and edible plant resource developed in Guizhou Province.It contains vitamin C,superoxide dismutase(SOD),polysaccharides,flavonoids and other functional ingredients.It has outstanding effects in antioxidant,lipid-lowering,anti-aging,anti-tumor and other aspects.The project team’s preliminary research found that the R.roxburghii juice fermented by Lactobacillus paracasei SR10-1(FR)had a significant enhancing effect on immunocompromised mice,and further exploration of the functional components of FR is needed.Therefore,the effect of FR on the remission of ulcerative colitis induced by sodium dextran sulfate(DSS)in mice and its regulatory effect on gut microbiota was mainly studies in this thesis;At the same time,the characteristic metabolites and related metabolic pathways of FR were studied using the UHPLC-QTOF-MS metabonomics method to clarify the main functional components of FR.The main research results and conclusions are as follows:(1)The effects of FR on the physiological status of ulcerative colitis mice were studied.The results showed that FR could improve the symptoms related to colitis in mice including reducing disease activity index,increasing colon length and reducing spleen coefficient.SR10-1 fermented R.roxburghii juice high-dose group(RH)and Vc control group(Vc)can significantly reduce the level of MPO(P<0.05),while the group P,group RL,group RM,group RH,group R and Vc can significantly reduce the content of IL-1 β,IL-6,IFN-γ and MDA(P<0.05).The content of IL-17 and IL-10 in group RH were significantly decreased(P<0.05);Group RL,RM,RH,R and Vc could significantly increase the activity of SOD(P<0.05);Group RL and RH could significantly increase the content of GSH(P<0.05).Group P,RM,R,CL and Vc could significantly increase the expression of MUC2(P<0.05).Group P,RL,RM,RH and R group could significantly increase the expression of Claudin-3(P<0.05),group RL,RM,R and CL could significantly increase the expression of ZO-1(P<0.05),group RL,RM and CL could significantly reduce the expression of Nrf2(P<0.05);Group P,RM,RH,R and Vc could improve the pathological damage of colon mucosa in mice.The above results indicated that FR could alleviate ulcerative colitis of mice by regulating the expression of inflammatory factors,oxidative stress indicators and intestinal barrier related genes in mice with colitis.Among them,the group RH was the best one.(2)The effect of FR on the gut microbiota of mice with ulcerative colitis was studied by analyzing the structure and composition of gut microbiota in mice.The results showed that FR could increase the diversity of gut microbiota and regulate the imbalance of gut microbiota in mice with colitis.Compared with the model group,at the phylum level,the relative abundance of Proteobacteria and Actinobacteria in the group RM decreased,while the relative abundance of Firmicutes increased;At the family level,the relative abundance of Odoribacteraceae,Desulfovibrionaceae,Chitinophagaceae and Clostridiaceae decreased in the groups RM and RH;At the genus level,the relative abundance of Desulfovibrio,Ruminococcus and Odoribacter were decreased in the group RM;At species level,the relative abundance of Desulfovibrio C21＿c20 in group RM and RH decreased,and the relative abundance of B.acidifaciens increased;Through functional prediction analysis,group RH could significantly improve cell apoptosis,endocytosis,meiotic yeast and p53 signal pathway.(3)The quality of FR was analyzed by using the metabolomics of UHPLC-QTOF-MS.The results showed that functional differential metabolites such as Erythromycin D,20,26-dihydroxyecdysone,Sambutoxin,Corchoruside C,European Ia1,Dolastatin 11,Phaeanharine,Swainsonine,Goyaglycoside g and Gracilin in FR were upregulated compared with R.roxburghii juice.The main metabolic pathways related to the FR included monoterpene biosynthesis,amino acid biosynthesis,flavonoid biosynthesis,flavonoid and flavonol biosynthesis,alanine,aspartic acid and glutamic acid metabolism,arginine and proline metabolism,tyrosine metabolism,etc.Among them,the functional metabolic substances related to the FR were mainly monoterpenes(menthol,linalool,geniposide),flavonoids(phloretin,geranium),amino acids(L-isoleucine,citrulline,L-histidine,L-aspartic acid),etc. |
