To explore the hydroxy-alpha-sanshool (HAS) effects on the intestinal metabolites of insulin-resistant mice, the blank group (BG), model group (MG), and HAS dose group (DG) were designed. The insulin resistance (IR) model was induced through streptozotocin (STZ) combined with a high-fat and high-sugar diet. Based on the availability of the model, the HAS dose was given by gavage for 28 days. The determination of cecum and key serum indexes was made, including the contents of insulin (INS), triglycerides (TG), total cholesterol (TC), glycosylated serum protein (GSP), and glycosylated hemoglobin (GHb). The changes in gut microbiota and metabolites in cecal contents were detected by 16S rRNA gene amplicon sequencing and UPLC/HRMS technology, respectively. The results that the levels of GSP, GHb, TG, and TC were significantly increased; this was not the case for INS; or for the changes in the gut microbiota and metabolites in MG. However, the intervention of HAS effectively reversed these changes, for instance, it decreased levels of GSP, GHb, TG, TC, and alterations of metabolite composition for linoleic acid and tyrosine metabolism and recovered trends of declining species diversity and richness of the gut microbiota in MG. It was indicated that HAS alleviated IR by regulating the gut microbiota and metabolites and affecting lipid and amino acid metabolism pathways.

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To explore the mechanism of Rosa roxburghii juice browning, this experiment was based on nontargeted metabolomics to study the effects of browning on the nutrition, flavor, metabolites, and metabolic pathways of R. roxburghii juice before and after storage. The results showed that the total soluble solids, superoxide dismutase (SOD), vitamin C (VC), total phenol, and total flavonoid of R. roxburghii juice decreased significantly before and after storage. The color difference value ∆E, browning index, and flavor and taste of R. roxburghii juice changed significantly (p < 0.05). A total of 541 metabolites were detected before and after browning of R. roxburghii juice by nontargeted metabolomics, including 435 differential metabolites, of which 221 were upregulated, and 214 were downregulated. The differential metabolites were mainly amino acids and peptides, carbohydrates, and carbohydrate conjugates. There were a total of 76 metabolic pathways enriched by differential metabolites, involving mainly galactose metabolism; alanine, aspartate and glutamate metabolism; and pantothenate and CoA biosynthesis. The experimental results showed that after browning of R. roxburghii juice, VC, total phenol, total flavonoid, and SOD activity were seriously lost, and the flavor deteriorated. The contribution of differential metabolites and metabolic pathways to the browning of R. roxburghii juice was sugar metabolism > amino acid metabolism > ascorbate and aldarate metabolism > phenols.