Rosa roxburghii Tratt is abundant in a variety of active ingredients, which exhibit regulatory effects on gut microbiota, hypoglycemic and hypolipidemic activities, and antioxidant properties. However, the impact of probiotic-fermented Rosa roxburghii Tratt juice on obesity and related complications remains unclear. Thus, using a high-fat diet (HFD) mouse obesity model and comparing it to the model group after 56 d of consecutive gavage with probiotic fermented Rosa roxburghii Tratt juice (FRTJ), Rosa roxburghii Tratt juice (RTJ), saline, and orlistat, respectively, we investigated the effect of FRTJ on obesity and related complications in this study. In HFD-induced obese mice, FRTJ supplementation significantly reduced fat accumulation and improved dyslipidemia, liver inflammation, endotoxemia, and colonic mucosal damage compared to the model group (MC). Moreover, FRTJ treatment was superior to RTJ treatment. FRTJ intervention dramatically improved the diversity and changed the composition of gut microbiota for the better. Compared with the MC group, the ratio of Firmicutes to Bacteroidetes at least decreased by 40.93% after FRTJ supplementation. Additionally, the FRTJ intervention led to a significant enhancement in the presence of beneficial bacteria, including Bacteroidetes, Lactobacillaceae, Lachnospiraceae, Corynebacteriaceae, Lactobacillus, Akkermansia, and Clostridium_XlVa. Conversely, the relative abundance of harmful bacteria such as Firmicutes, Porphyromonadaceae, Desulfovibrionaceae, Erysipelotrichaceae, Allobaculum, Barnesiella, and Desulfovibrio was observed to decrease. The results of the correlation analysis revealed that the following bacteria had different relationships with body weight: Bacteroidetes, Acidobacteria, Proteobacteria, Lactobacillaceae, Lactobacillus, Tenericutes, and Saccharibacteria had negative correlations with body weight (P < 0.05), while Allobaculum, Paenalcaligenes, Barnesiella, SR1, Porphyromonadaceae, Firmicutes, and Deferribacteres were positively correlated with body weight (P < 0.05). In addition, we conducted antibiotic intervention experiments to assess the effects of FRTJ on the gut microbiota. The results showed that antibiotic treatment eliminated all metabolic improvements mediated by FRTJ, suggesting that the beneficial effects of FRTJ on obesity symptoms and associated metabolic disorders are exerted by regulating gut microbiota composition.

This study mainly investigated the regulatory effect of Rosa roxburghii Tratt fruit juice fermented by Lacticaseibacillus paracasei SR10-1 (LAB-RRTJ) on modulating gut microbiota in dextran sulfate sodium (DSS)-induced ulcerative colitis in mice. Compared to control group, DSS induction decreased body weight of mice, indexes of Shannon, Simpson, Chao1 and Faith_pd, and increased disease activity index (DAI) and levels of interleukin 1β (IL-1β), IL-6, tumor necrosis factor α (TNF -α) and interferon-γ (IFN-γ); And this induction also led to an increase in Proteobacteria, Verrucomicrobia and Actinobacteria at phylum level, harmful bacterial species richness at genus level, and relative richness of S. sciuri, Desulfovibrio C21_c20, R. gnavus and Akkermansia muciniphila at species level, and a decrease in Firmicutes at phylum level and relative richness of B. acidifaciens in mice. LAB-RRTJ increased body weight of mice with DSS induced ulcerative colitis (UC) and indexes of Shannon, Simpson, Chao1 and Faith_pd, reduced DAI and the content of four inflammatory factors and improved gut microbiota imbalance in DSS induced UC mice. Besides, the number of operational taxonomic units (OTUs) increased, α-diversity and β-diversity were restored and similar to those in mice in the control group after LAB-RRTJ treatment. Compared with the positive drug treatment group, LAB-RRTJ has a better effect on regulating gut microbiota diversity in colitis mice. Correlation analysis showed that inflammatory factors were positively correlated with harmful bacteria and negatively correlated with beneficial bacteria which commonly found in some colitis mice. Taken together, our study demonstrated that LAB-RRTJ could alleviate DSS-induced colitis in mice through the modulation of inflammatory cytokines and gut microbiota composition.