Research And Development Of Biogenic Fermented Milk And Its Effect On Improving Lipid Metabolism In High-fat Diet Mice

Hyperlipidemia is a kind of metabolic disease that causes the disorder of lipid metabolism,and causes serious harm to human life and health.At present,the lipid-lowering function of prebiotics and probiotics has become a hot research topic.Biossein is a combination of prebiotics and probiotics.By organically combining the two,it maximizes its lipid-lowering function.In this paper,prebiotics and probiotics with the optimal lipid-lowering function and the most significant interaction between proliferation and interaction were screened out through in vitro lipid-lowering test and in vitro proliferation culture test.They were used as raw materials to develop synbiogenic fermented milk and optimize the process.Animal experiments were carried out to study the improvement of lipid metabolism in high-fat diet mice.The aim is to develop a syngenized fermented dairy product that can not only meet people’s taste needs but also play a role in reducing fat.The main results are as follows:(1)60 kinds of widely studied foodborne polysaccharides with lipid-lowering functions and 4 kinds of common prebiotics were selected as raw materials.In vitro lipid-lowering experiments,it was found that the binding rates of longan meat polysaccharides,flavanols polysaccharides and mulberries polysaccharides with sodium glycholic acid were the highest,which were 52.10%,51.69% and 49.86%,respectively.The highest binding rates of sodium taurocholate were 51.51%,50.91% and 50.60%,respectively.The inhibitory rates of longan meat polysaccharide,polyspermophyllum flavorum polysaccharide and mulberry polysaccharide on pancreatic lipase were 53.60%,51.09% and 50.75%,respectively.Therefore,these three kinds of foodborne polysaccharides were used as candidate test materials for lipid-lowering prebiotics.(2)The optimal temperature,growth curve,acid production,acid tolerance,bile salt tolerance,simulated human gastrointestinal environment,cholesterol lowering ability and triglyceride lowering ability of 32 strains of Lactobacillus plantarum were measured to evaluate their probiotic properties and lipid lowering function.The results showed that Lactobacillus plantarum FS5-5,Lactobacillus plantarum FSDJ-15-1,Lactobacillus plantarum WW and Lactobacillus plantarum FSDJ-5-1 all had good probiotic properties.The survival rates under acid condition were 59.73%,52.20%,47.65% and 49.15%,respectively.The survival rates under bile salt were 58.64%,53.58%,54.13% and 55.36%,respectively.The survival rates were 45.31%,38.88%,36.89% and 32.14% under simulated human gastrointestinal environment,respectively.Lactobacillus plantarum FS5-5,Lactobacillus plantarum WW and Lactobacillus plantarum FSDJ-15-1 all had good lipid lowering function.The removal rates of cholesterol were 81.11%,76.15% and 75.33%,respectively.The degradation rates of triglyceride were 45.38%,48.96% and 44.38%,respectively.Therefore,Lactobacillus plantarum FS5-5,Lactobacillus plantarum FSDJ-15-1 and Lactobacillus plantarum WW,which have the best probiotic properties and lipid lowering function,were selected as candidate materials of lipid-lowering probiotics.(3)The proliferation effects of three kinds of foodborne polysaccharides on three strains of Lactobacillus plantarum were compared by the proliferation index.The results showed that three kinds of foodborne polysaccharides had the most significant proliferation effects on Lactobacillus plantarum FS5-5 and Lactobacillus plantarum WW.The proliferation of Lactobacillus plantarum FS5-5 was ranked as Longan meat polysaccharide(2.79)>.Mulberry polysaccharide(1.99)& GT;Polygonatum polygonatum polysaccharide(1.10);The order of lactobacillus plantarum WW proliferation was Longan meat polysaccharide(2.36)>.Mulberry polysaccharide(2.08)& GT;Polygonatum polysaccharide(0.75).Because Lactobacillus plantarum FS5-5 has better probiotics and lipid lowering function than Lactobacillus plantarum WW,and longan meat polysaccharide can promote the proliferation of Lactobacillus plantarum FS5-5 to the greatest extent,so we selected Lactobacillus plantarum FS5-5 and Longan meat polysaccharide to jointly develop biogenic fermented skim milk and process optimization.On the basis of single factor test,response surface analysis method was used to determine the optimal concentration of fermented skim milk,the optimal inoculation amount of Lactobacillus plantarum FS5-5 and the optimal addition amount of longan meat polysaccharide were 21%,4% and 4%,respectively.(4)Animal experiments were carried out to evaluate the improvement of lipid metabolism in high-fat diet mice.The results showed that the biogenic fermented milk had the best lipid lowering function.Compared with high fat model group,the serum levels of TC,TG,LDL-C,ALT,AST,MDA and TBA in symbiosis fermented milk experimental group were decreased by 27.08%,17.88%,29.41%,45.04%,27.71%,28.44% and 26.43%,respectively.The levels of TC,TG,LDL-C,ALT and AST in liver of mice decreased by30.55%,22.64%,20.68%,19.15% and 28.22%,respectively.The level of HDL-C in serum and liver of mice increased by 67.85% and 60.00%,respectively.TC,TG and TBA levels in feces of mice increased by 38.63%,38.77% and 30.66%,respectively.