Effects Of Jerusalem Artichoke From Saline-alkali Land On Metabolism And Gut Microecology In Diabetic Mice And Development Of Product

In this study,inulin(SI,HI,HNI,NXI and SXI)were extracted from Jerusalem artichoke in different saline-alkali regions by thermal maceration.Fourier infrared spectroscopy,X-ray diffraction,high-performance gel permeation chromatography and high-performance liquid chromatography were used to investigate the basic structural properties and physiological activities of inulin.The mouse model of type 2 diabetes(T2D)was established to study the effects of SI and HI on fasting blood glucose,serum biochemical indices,cardiac inflammatory factors and pathological sections of T2 D mice.The effects of SI and HI on gut microbiota and metabolites in T2 D mice were explored by 16 S r DNA sequencing and metabolomics technologies to further develop their intervention mechanisms.In addition,HI was chosen as the raw material for jelly sweets,and the products were evaluated by texture,sensory evaluation,freeze-thaw stability and glucose generation rate.The main research contents and results include the following:1.Preparation of inulin from different saline-alkali soils and their structure and properties analysisThe inulin(SI,HI,HNI,NXI and SXI)was prepared from saline-alkali Jerusalem artichoke by thermal maceration.The structures and properties of SI,HI,HNI,NXI and SXI were researched,the results showed that all five groups of samples were pyran polysaccharides linked by α-glycosidic and β-glycosidic bonds;the monosaccharide composition was all fructose and glucose;their crystals were all amorphous;the molecular weights of the samples were 535 Da,3236 Da,2916 Da,720 Da and 514 Da,respectively,sequentially.The in vitro digestibility and antioxidant activity of the five groups of samples were measured,and the results showed that at sample concentrations up to 5 mg/m L,the scavenging rates of DPPH,ABTS and hydroxyl radicals reached59.09%,39.96% and 29.95% for SI;62.97%,44.56% and 31.97% for HI;51.93%,37.74%and 27.07% for HNI;55.98%,40.57%,and 30.12% for NXI and 58.73%,41.64%,and30.87% for SXI,respectively.It showed that the samples all had some antioxidant capacity.The reducing saccharide content of SI,HI,HNI,NXI and SXI samples were not significantly modified during simulated gastrointestinal digestion,indicating that these were not available for gastrointestinal digestion and had potential prebiotic properties.2.Effect of different molecular weights of inulin on physiological indexes of T2 D miceA STZ-induced T2 D mouse model was constructed,and the changes of fasting blood glucose,serum biochemical indexes,cardiac inflammatory factors and pathological sections of T2 D mice were observed after 6 weeks of dietary intervention with SI and HI with different molecular weights,respectively.The results showed that both SI and HI could effectively improve the symptoms related to T2 D,and the levels of fasting blood glucose,serum biochemical indexes and cardiac inflammatory factors were effectively improved,and the morphological lesions such as myocardial cell necrosis an d edema were effectively alleviated.Among them,the intervention effect of HI was better.3.Effects of different molecular weights of inulin on gut microorganisms and metabolites in T2 D miceThe effects of SI and HI on gut microorganisms and their metabolites in the feces of T2 D mice were examined by 16 S r DNA sequencing analysis and metabolomic analysis.The results showed that the structural diversity of the gut microbiota was significantly improved after SI and HI interventions,mainly by decreasing the abundance of Clostridium sensu stricto 1 and increasing the abundance of Muribaculum,while correlation analysis showed that the alterations in the abundance of these two genera were significantly correlated with TC,LDL-C,TGF-β,CK-MB,LDH,IL-1β,TNF-α and SDF-1β.The main differential metabolites were indole-3-pyruvvic acid,DL-tryptophan,kynurenic acid,bile acid,lithocholic acid,deoxycholic acid,leukotriene f4,arachidonic acid,prostaglandin i2,prostaglandin h2,sphingosine,D-erythro-sphinganine-1-phosphate and psychosine,and the metabolic pathways involved were tryptophan metabolism,bile acid metabolism,arachidonic acid metabolism and sphingolipid metabolism.4.Product development of edible jelly sweets with inulinSingle-factor and orthogonal experiments were conducted to determine the best solution for jelly sweets,which was then evaluated for the product.The results showed that the optimized solution with 60% HI content,4% vanillin content and 8% sodium carbonate content produced better jelly sweets in terms of hardness,chewiness,freezethaw stability and slowed glucose production compared with a commercially available gel product.