The Regulation Effect Of Flavonoids From Huyou And Probiotic Fermented Huyou Juice On Lipid-lowering And Intestinal Microbiota

Grapefruit is a special fruit variety originated in Zhejiang Province,which has rich nutrients and pharmacological effects.In order to develop the healthy functions of Huyou products,the bioactive substances of flavonoids and probiotic fermented Huyou juice were taken as the research objects.By using the high-throughput sequencing technology,the regulation of human intestinal microbiota was studied to provide theoretical basis for weight loss and health functions of Huyou.The ultrasonic-assisted ethanol extraction method was used to extract flavonoids from Huyou.The extraction process was investigated by single factor experiments and optimized by response extraction surface analysis method.The optimal extraction process was determined as follows: the ratio of material to liquid was 1:12,the concentration of ethanol was 70%,the extraction time was 20 minutes,and the total flavonoid content in Huyou flavonoid extract was 3.72mg/g.Obesity mice model was established by high-fat diet induction.After 8 weeks' administration of Huyou flavonoids,we observed a significantly decrease in weight of the mice.Huyou flavonoids significantly decreased the contents of serum TC,TG and LDL-C,increased the content of HDL-C,and the level of blood lipid returned to normal.16S rDNA sequencing technology was used to analyze the fecal intestinal microbiota of mice.The results showed that flavonoids from Huyou significantly increased the diversity of intestinal microbiota in obesity mice,increased the relative abundance of Bacteroidetes,and decreased the relative abundance of Firmicutes.By increasing the relative abundance of beneficial bacteria such as Bifidobacterium,Blautia,Akkermansia,etc.,the intestinal microbiota of mice is changed favorably,and metabolic disorder caused by obesity was improved.Humanized intestinal microbiota obesity mice model was established.The mice were fed with fermented and unfermented Huyou juice for 8 weeks,which significantly relieved the weight gain and abnormal blood lipid levels of obese mice,and the antioxidant level of liver was improved.We observed a decrease both in the accumulation of fat in liver tissue and the levels of AST and ALT,but they cannot be completely restored to the normal state,which reduced liver damage caused by obesity to a certain extent,and the effect of fermented Huyou juice was better.16S rDNA sequencing technology was used to analyze the intestinal microbiota of obese mice.The intervention of fermented Huyou juice significantly improved the diversity of intestinal microbiota,and played an active role in regulating the composition and structure of intestinal microbiota at different levels of phylum,order,family and genus,respectively.The relative abundance of beneficial bacteria such as Bacteroides,Roseburia,Butyrivibrio,Lactobacillus,Akkermansia,etc.increased,which had a positive impact on the metabolism of obese hosts through the production of short-chain fatty acids,enhancing intestinal barrier,and reducing intestinal inflammation.