Development Of Millet Bran Dietary Fiber Meal Replacement Powder And Its Preventive Effects Against Colitis

Rationales:Millet bran is the by-product produced in the process of millet milling and is rich in dietary fiber and other active ingredients.However,millet bran is mostly used as animal feed,which is not processed and utilized in more depth,resulting in the waste of millet bran.Dietary fiber is the main component of millet bran,which is a carbohydrate that is difficult to be digested and absorbed by intestine.It can promote intestinal health,such as promoting defecation,regulating intestinal flora,and reducing intestinal mucosal inflammation.Living conditions such as sedentary,negative emotions and a high-fat,highsugar diet can easily lead to slow intestinal peristalsis,dysbiosis of intestinal flora and damaged intestinal barrier,and even further induce ulcerative colitis.Ulcerative colitis is difficult to cure and easy to relapse,and its prevalence and incidence are increasing year by year,which brings life and economic burden to patients.Therefore,in this study,millet bran was developed as meal replacement powder which is beneficial to intestine and has certain function of preventing ulcerative colitis,which provides a basis for industrial development of millet bran and improves the economic benefit of millet bran.Objective: To prepare millet bran dietary fiber and meal replacement powder by optimizing the extraction process and formula,and to evaluate its preventive effect on ulcerative colitis.Methods:(1)Orthogonal tests was used to determine the optimal conditions for the extraction of dietary fiber from millet bran by α-amylase and papain with the content of reducing sugar after millet bran hydrolysis and the yield of soluble dietary fiber/protein in the products as indicators,and the composition of monosaccharides and physical and chemical properties of the dietary fiber products were determined.(2)To determine the optimal formula of cereal bran dietary fiber meal replacement powder,which composed of defatted millet bran superfine powder served as the base material,and grain powder,fruit powder and sweetener,and sensory evaluation,water absorption index and water solubility index were used as the indexes.The quality and safety tests were tested to evaluate its consumption safety.(3)DSS was employed to induce ulcerative colitis,and the preventive effects of millet bran dietary fiber,millet bran dietary fiber meal replacement powder and commercially available Nutrilite fiber powder on ulcerative colitis were evaluated from the aspects of disease activity index,colonic inflammation status,intestinal barrier function and intestinal secretory function in mice.Fecal metabolomics and microbiomics were performed to focus on the potential biomarkers and metabolic pathways.Results:(1)The best conditions for extracting dietary fiber from millet bran were α-amylase(350 U/g,70 ℃,p H 7.0,2.5 h)and papain(100 U/g,60 ℃,p H 7.0,1.5 h).The monosaccharide composition of dietary fiber was rich and different from different sources.Soluble dietary fiber mainly contains glucose,and a small amount of galactose,arabinose and xylose,while insoluble dietary fiber mainly composed of arabinose,xylose,and a small amount of glucose and galactose.Compared with rice bran dietary fiber and wheat bran dietary fiber,the water holding capacity and swelling capacity of millet bran dietary fiber showed no statistically significant difference,suggesting that millet bran dietary fiber could be used in the development of meal replacement meal powder as rice bran and wheat bran.(2)The best formula of millet bran dietary fiber meal replacement powder was 30%defatted bran ultra-fine powder,25% soybean powder,20% tartary buckwheat powder,15%corn powder,0.06% cysiae and 9.94% apple powder.The results of quality and safety test showed that the mycotoxins(zearalenone,ochratoxin and aflatoxin),pesticide residues(carbendazim,imidacloprid,acetamidine,organophosphorus and carbamate pesticides)and pollutants(lead,chromium,cadmium,mercury and arsenic)in the millet bran were all in line with the national standards,which proved the edible safety of the millet bran and meal replacement powder.(3)Millet bran dietary fiber,meal replacement powder and commercial Nutrilite fiber powder can all relieve hematochezia,immune disorders,abnormal colonic morphology and intestinal barrier damage in mice with ulcerative colitis to different degrees.This results indicate that millet bran dietary fiber and meal replacement powder have a certain role in preventing ulcerative colitis.Further fecal metabolomics and microbiome correlation analysis focused on the phenylalanine,tyrosine,and tryptophan biosynthetic pathway,which may be one of the mechanisms of dietary fiber diet in preventing ulcerative colitis.In the 12 different bacteria,g＿Lactobacillus can alleviate colon inflammation,f＿Moraxellaceae can promote inflammation.While o＿Bacteroidales and g＿Corynebacterium contained both beneficial and opportunistic bacteria,which could inhibit and promote inflammation.Pathway analysis combined with correlation analysis with the microbiota suggests that a high dietary fiber diet may improve ulcerative colitis by promoting indole metabolism and kynurenic acid metabolism of tryptophan,regulating intestinal microbial homeostasis,inhibiting inflammation,and promoting intestinal barrier repair.This indicates that the millet bran meal replacement powder can be used as a supplementary source of dietary fiber,and has a certain role in protecting intestinal tract and preventing ulcerative colitis.Compared with millet bran dietary fiber and Nutrilite fiber powder,millet bran dietary fiber meal replacement powder has a wider regulatory effect on the body,and its preventive effect on ulcerative colitis is better than the former two.Conclusion: In this study,the extraction conditions of millet bran dietary fiber were optimized,and the millet bran dietary fiber meal replacement powder was prepared.The millet bran and meal replacement powder can be used as a supplementary source of dietary fiber,which has certain effects of protecting intestine and preventing ulcerative colitis.It provides an experimental basis for the industrial development and application of millet bran.