Characteristics Of Probiotic Fermented Whole Soymilk And Its Effect On Blood Lipids And Intestinal Flora In Hyperlipidemic Mice

Probiotics are a class of active microorganisms that can improve the ecological balance of microorganisms,regulate intestinal flora,reduce cholesterol,and promote human health.Probiotics can maintain the permeability of the intestinal mucosa,resist cancer and mutation,improve alcoholic liver damage,reduce serum cholesterol levels,anti-inflammatory,anti-tumor,and lower blood pressure.Fermented soymilk refers to a fermented milk product with soy flavor formed by the fermentation of sterilized soymilk by probiotics.It retains the original nutritional value of soymilk while producing active peptides that have a therapeutic effect on high blood pressure.Oligosaccharides that help digestion and absorption of the gastrointestinal tract,?-aminobutyric acid that stimulates neurons to keep excited,and other biologically active substances that are beneficial to the health of the body.In addition,through the fermentation of probiotics,the bound soy isoflavones are converted into free soy isoflavones,making it easier to be absorbed by the human body.At present,there are very few reports on the combination of probiotics and fermented soymilk in regulating blood lipid metabolism and intestinal flora structure in hyperlipidemia mice.Therefore,this article first selects casei,L.acidophilus,and L.plantarum to ferment whole soymilk to study its fermentation characteristics.Through comparison,the most suitable fermented whole soymilk is obtained.Secondly,three strains of probiotics were used to ferment whole soymilk separately to interfere with high-fat diet mice.The experiment is divided into 6 groups:normal control group(A),high-fat model group(B),L.casei fermented soymilk intervention group(C),L.acidophilus fermented soymilk intervention group(D),L.plantarum fermented soymilk The intervention group(E)and the unfermented soymilk intervention group(F)were given intragastric administration for 8 weeks.Explore its effect on blood lipid levels and liver oxidative damage in hyperlipidemia mice,and its regulatory effect on the structural disorder of intestinal flora in mice caused by hyperlipidemia.The results are as follows:(1)During the fermentation of the three probiotics,the pH of the soymilk decreased significantly,while the titer acidity and apparent viscosity increased significantly,and the number of viable bacteria of the fermented whole soymilk could reach 108 cfu/mL.At the end of fermentation,the content of free soy isoflavones in whole soymilk fermented by L.plantarum was significantly higher than that of the other two strains.The content of daidzein reached 10.53 ?g/mL,3.4 times that of the unfermented soymilk,and the highest genistein was 19.91 ?g/mL,which is 8.4 times that of the unfermented soymilk.Therefore,L.plantarum is suitable for fermenting soymilk with high nutritional value.The fermented whole soymilk obtained by fermentation of L.casei has a smooth and firm appearance,soft color,good product shape retention,a small amount of whey precipitates,a suitable ratio of sweet and sour,no beany taste,delicious taste,and conforms to popular tastes.Therefore,L.casei is more suitable for fermenting and exporting soymilk with good taste.(2)Through the determination of experimental animal liver slices,body weight intake,blood lipid levels and liver oxidative damage indicators,the effects of three probiotic fermented whole soymilk on the improvement of hyperlipidemia-induced disorders of blood lipid metabolism in mice were analyzed.The results show that three probiotics fermented whole soymilk can effectively reduce weight gain caused by high-fat diet and improve liver damage.Significantly reduce the levels of TC,TG,LDL-C in the serum and liver of hyperlipidemia mice(P<0.05),increase the level of HDL-C in the serum(P<0.05),and significantly reduce the serum levels of hyperlipidemia mice ALT and AST levels(P<0.05),reduce lipid oxidation product MDA levels(P<0.05),increase the activity of SOD and GSH-Px enzymes in the liver,thereby improving blood lipid metabolism disorders in mice caused by hyperlipidemia.By comparison,the intervention effect of Lactobacillus plantarum fermented whole soy milk group was the best.(3)Through 16S rRNA sequencing technology,the changes of mouse intestinal flora were analyzed.To evaluate the regulating effect of three strains of probiotics fermented whole soy milk on the intestinal flora disorder of mice caused by hyperlipidemia.The results showed that the high-fat diet would cause the structure of the intestinal flora in mice to be messy,and the F/B value was significantly higher than that of the normal group(P<0.01),while the F/B value of the three probiotics fermented whole soymilk group was significantly lower In the high-fat group(P<0.05).Compared with the high-fat group,the three probiotics fermented whole soymilk group can increase the relative abundance of probiotics(Lactobacillus-Lactobacillus),(Bacteroides-Norank_fMuribaculaceae)and acid chain fatty acid-producing bacteria(Laospirillum-Lachnospiraceae_UCG-006,Lachnospiraceae_NK4A136_group),but reduce Relative abundance of pathogenic bacteria(Lacunar-Lachnoclostridium,Broutella-Blautia).Improve the intestinal flora disorder of mice caused by hyperlipidemia.In summary,L.casei is more suitable for fermenting soymilk with good taste.Three probiotics fermented whole soymilk can effectively reduce the increase in blood lipid levels in hyperlipidemia mice,improve liver damage caused by hyperlipidemia,and enhance the antioxidant capacity in the body.Among them,the L.plantarum fermented whole soymilk group has the best effect excellent;In addition,the three probiotics fermented whole soymilk group has a regulatory effect on the changes in the structure of the intestinal flora in mice caused by hyperlipidemia,and promotes the development of the intestinal flora in mice in a healthy direction.