Effect Of Soluble Dietary Fiber On Intestinal Microflora In Fermented Soybean Residue By Neurospora

The soluble dietary fiber content was significantly increased after the fermentation of soybean residue.Soluble dietary fiber can play an important role in intestinal flora.In this study,soluble dietary fiber was used as a research object.The composition of oligosaccharides in fermented soybean residue was analyzed.The extraction process of polysaccharide in fermented soybean residue was optimized.The functional properties of oligosaccharides and polysaccharides in fermented soybean residue were studied by in vitro fermentation.The effects of soluble dietary fiber in fermented soybean residue on serum biochemical parameters and intestinal microbial diversity were studied by animal experiments.The main results are as follows:1.The composition of the oligosaccharides of fermented soybean residue was sucrose,raffinose and stachyose,and the percentage was 40.3%,5.1%,15.6%respectively.The optimum process parameters were obtained by single factor experiment and orthogonal experiment.The extraction time was 2 times,the ratio of water to material was 20:1,the bath temperature was 100 ? and the bath time was 3h.Under these conditions,the yield of polysaccharide in fermented soybean residue was 17.90%.2.The results showed that the oligosaccharides and polysaccharides in fermented soybean residue had a certain effect on the proliferation of Lactobacillus plantarum NCU116 and Bifidobacterium adolescentis CICC 6178.The maximal absorbance,pH reduction value and substrate consumption rate(p<0.05)of the fermentation broth of Lactobacillus plantarum NCU116 of 2 g/L oligosaccharides and polysaccharides of fermented soybean residue groups were lower than those of 2g/L inulin group(positive control group).The maximal absorbance,pH reduction value and substrate consumption rate(p<0.05)of the fermentation broth of Bifidobacterium adolescentis CICC 6178 of 2 g/L oligosaccharides and polysaccharides of fermented soybean residue groups were higher than those of 2g/L inulin group.The maximum growth rates of all the oligosaccharides of fermented soybean residue groups to the two probiotics were greater than those of 2g/L inulin group,the lag parameters of Lactobacillus plantarum NCU116 of 2 g/L,6g/L oligosaccharides of fermented soybean residue groups were less than those of 2g/L inulin group.The lag parameters of Bifidobacterium adolescentis CICC 6178 of all the oligosaccharides of fermented soybean residue groups were longer than 2 g/L inulin group.The lag parameters of the two probiotics of all the polysaccharides of fermented soybean residue groups were longer than 2 g/L inulin group.3.The addition of oligosaccharides and polysaccharides in fermented soybean residue could increase the cumulative gas production could increase the cumulative gas production,the maximum theoretical yield,the rate of gas production and the content of short chain fatty acids,reduce the delay time of gas production and pH,NH3-N content can be reduced in some time.When the amount of 2 g/L was the same,the oligosaccharides and polysaccharides of fermented soybean residue were not as good as in vitro fermentation of inulin.4.Animal experiments showed that the total protein content of the total soluble sugar of soybean residue and the polysaccharide of fermented soybean residue was higher than that of the total soluble sugar of fermented soybean residue(p<0.05).The content of triglyceride in the total soluble sugar of soybean residue group was lower than that in the polysaccharide of fermented soybean residue group(p<0.05).The content of low density lipoprotein cholesterol in the polysaccharide of fermented soybean residue group was lower than that of the total soluble sugar of fermented soybean residue group(p<0.05).High-throughput sequencing of the sample pretreatment and data acquisition work better.The microbial diversity were the lowest in the total soluble sugar of soybean residue and the polysaccharide of fermented soybean residue group,the control group had the highest microbial diversity.In each group,the dominant groups in the classification level of Phylum,Class,Order and Family were all the same: Bacteroidetes(64.98±11.07)% and the Firmicutes(21.42±7.68)%,Bacteroidia(64.35±11.60)% and Clostridia(11.45±0.93)%,Bacteroidales(64.35±11.60)% and Clostridiales(11.45±0.93)%,Prevotellaceae(46.29±11.07)%.The content of Bifidobacteriales andBifidobacteriaceae in the total soluble sugar of soybean residue group was the highest in all groups(8.55%).The contents of Lactobacillales and Lactobacillaceae in the total soluble sugar of soybean residue and the oligosaccharides of fermented soybean residue group were relatively high,which were 2.80% and 2.20%,respectively.The results showed that the oligosaccharides in fermented soybean could increase the number of Lactobacillus in the caecum of rats,the polysaccharides in fermented soybean could improve the cecal microflora of rat.