The Effect Of Neurospora. Crassa Fermentation On The Nutrional Components In Soybean Residue And The Extraction And Purification Of Polysaccharide

The objective strain (the strain was identified as Neurospora. Crassa by our Lab before) was screened from a traditional fermented soybean residue food in Jiangxi province. This paper aimed to experimentally determine the changes of nutritional components between fresh soybean residues and the soybean residues being fermented by Neurospora, Crassa, then explore the extraction process of oligosaccharides and polysaccharides from the fermented soybean residues. Provide theoretical guidance for producting new fermented soybean residue goods and achieving comprehensive utilization of soybean residue.1. Comparison of the changes of moisture, ash, fat, water-soluble sugar, isoflavones, fatty acid, carotenoids and other nutrients between fresh soybean residues and fermented soybean residues. The content of fat dropped from 8.07% down to 5.76%, the content of soluble polysaccharides increased from 28.86% to 62.50%, the content of isoflavones increased from 0.60mg/g to 0.66mg/g, the output ofβ-carotene pigment reached to 8.06μg/g after fermentation.2. Determinated the content of total protein in fresh soybean residues and the Neurospora. crassa fermented soybean residues by using micro-Kjeldahl method. The content of crude protein increased by 24.66% to 32.59%, The protein digestibility was determinated by using pepsin-trypsin digestion in vitro: the protein digestibility rised from 6.86% to 14.97% after fermented by Neurospora.crassa. Determined the contents and types of amino acids and free amino acids in soybean residues and fermented soybean residues by using Waters AccQ-Tag method: the contents and types of amino acids and free amino acids in soybean residue were significantly increased after fermentation. The resultes suggested that the protein nutritional value of soybean residues is enhanced by fermented.3. Using improved Southgate determined total dietary fiber content in fresh soybean residue and the soybean residue fermented by Neurospora. Crassa. And the contents of water-soluble-non-peptic polysaccharide, water-insoluble-non-cellulosic polysaccharides, cellulose, lignin were 0.2595%, 37.1387%, 12.8710%, 3.2358% and 0.1848%, 0.5384%, 7.7261% and 3.1729%. The study found that Neurospora. Crassa could degradate most water-insoluble-non-cellulosic polysaccharides and cellulose, but it almost has no effect on lignin.4. Using the total quantity of carbohydrate content and the harvest yields of oligosaccharides as the criterion, investigated the effect of extract condition on extract rate of influence of fermented soybean residue oligosaccharides and polysaccharides. The optimum extraction condition was found to be as follows: Extraction times: twice, 1 hour per time; Extraction water: 15 times the weight of the sample. AB-8 macroporous resin adsorption impurities and organic solvent extraction have been used in refining fermented soybean residues oligosaccharides. Established experimental basis for the industrial production of fermented soybean residues oligosaccharides.5. The fermented soybean residue polysaccharide solution was deposited by ethanol alcohol, decolored and removed protein, then polysaccharide S was achieved. S1 and S5 were achieved by isolation and purification with DEAE sephadex A-25 cellulose. SM1, SM5, SP5 were achieved by being further purifying with Sephacral S -200 gel column, and they were examined as homogeneous polysaccharides by Sephacryl S-300. Then, their molecular weights were measured by Sephacryl S-200 gel filitration for 137809, 105468, 95693. The infrared spectra of SM1, SM5, SP5 show typical characteristic absorption peaks. Analysis of SM1, SM5, SP5, GC showed that they had at least six-galactose monosaccharide components: rhamnose, arabinose, xylose, mannose, glucose, galactose.The content of protein and amino acid, in vitro digestibility of soybean residues had been improved by Neurospora.crassa fermentation. Fermentation process could also decline crude fiber, improve the content of soluble polysaccharides and oligosaccharides; increased isoflavone content of soybean residues; product a large amount of P-carotene. These results show that Neurospora.crassa fermentation can be greatly improved the nutritional and functional value of soybean residue, can be used for bean dregs traditional food industrial production, such as soybean residues.