The Research On Production Of Xylo-Oligosaccharides By Composite Enzymatic Hydrolysis From Bagasses Xylan

XOS as a kind of functional oligosaccharides, it is widespread concerned by people because of its ability to regulate intestinal flora, improve immunity,anti-tumor, reduce blood pressure and blood sugar. In the production process of XOS, how to improve XOS yield and reduce production costs is a urgent problem to be solved.In this thesis, bagasse as raw material, xylan extraction by alkali liquor, then use the compound enzyme hydrolysis bagasse xylan to preparation of xylooligosaccharides. Finally use high performance liquid chromatography analysis the bagasse xylan enzymatic hydrolysate, the results showed that:1.Take the concentration of bagasse xylan as assessment indicator, investigated the influence of NaOH concentration, hydrolysis time and the ratio of liquid to solid on bagasse xylan alkali extraction.On the basis of single factor experiments, the xylan extraction conditions after response surface optimize are:8.77%of the concentration of NaOH, hydrolysis time3.5h, the ratio of liquid to solid45:1, under these conditions, the concentration of bagasse xylan is9.28mg/mL2.Take the bagasse XOS yield as assessment indicator, investigated the influence of enzyme dosage, pH value,hydrolysis temperature and enzymolysis time on bagasse xylan enzymolysis.On the basis of single factor experiments, The XOS extraction conditions after response surface optimize are:enzyme dosage3.5%, pH value5.3, hydrolysis temperature46.0℃, enzymolysis time6h, under these conditions, the extraction rate of XOS is78.84%, and the average degree of polymerization is2.30.3.Complex xylanase A,xylanase B and alpha-L-arabinofuranosidase though simplex-centroid method for mixture experiments, make the XOS extraction rate as evaluation index, after analysis the composition of optimization compound enzyme is:xylanase A39.5%, xylanase B25%and alpha-L-arabinofuranosidase35.5%. under these conditions, the extraction rate of XOS is85.20%, the extraction rate of XOS increased by6.36%compared to the extraction rate of XOS though single xylanase hydrolysis bagasse xylan.4.The high performance liquid chromatography spectra of enzymatic hydrolysate though single xylanase hydrolysis bagasse xylan show that:in the enzymatic hydrolysate, XOS content of59.54%, Xylobiose content of32.14%, xylose content of12.93%. The high performance liquid chromatography spectra of enzymatic hydrolysate though compound enzyme hydrolysis bagasse xylan show that:in the enzymatic hydrolysate, XOS content of64.84%, xylobiose content of36.19%, xylose content of11.31%. Compared to single xylanase hydrolysis bagasse xylan, the XOS content increased by8.9%, the xylobiose content increased by12.6%, the xylose content reduced by12.5%in enzymatic hydrolysate of compound enzyme hydrolysis bagasse xylan.