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Inulin connected by β (1 → 2) bond of the polysaccharide by a D-fructose, the use of inulin as a raw material through degradation of inulinase one step may be prepared directly oligofructose and ultrahigh purity HFCS. The oligofructose is the function of a class of natural oligosaccharides, it has to improve the intestinal micro-environment, the regulation of lipid and blood sugar levels, the prevention of obesity, and to promote absorption of minerals and vitamin synthesis projecting physiological functions; Fructose having high sweetness and authentic, anti-caries, metabolic pathways from insulin to control. Many microorganisms capable of producing inulinase nature, but truly capable of high-yielding strains of inulinase rarely, in order to obtain a high-yielding strains of inulinase This paper carried out the study of the following three aspects: 1. Ultrasound strengthen extracting inulin in Jerusalem artichoke To explore the impact of ultrasound on Jerusalem artichoke inulin extraction test using single factor experiment and response surface methodology to study the extraction process, and analysis of the major influencing factors and the inulin extraction rate relationship the mathematical model. The test results show that the regression equation p = 0.00021 <0.01, the coefficient of determination R ~ 2 98.94%, indicating a good fit of the model with the experimental values. Optimize the process of ultrasonic extraction of inulin: total extraction time of 10min, ultrasonic irradiation 15s/6s, and ultrasonic power 750W, solid-liquid ratio of 1: 30.15 (w / v), extraction temperature of 40 ° C in conditions inulin extraction rate of 94.23%. Compared with the conventional hot water extraction method, the extraction rate of 26.25 percent. Production inulinase Strain strain in order to obtain a high yield of inulinase, test from Jerusalem artichoke rhizosphere soil and leaves through screening, separating purification and shake flask method rescreening screened a production of inulin enzyme maximum strain, and was identified as Aspergillus niger genus. Strains screened by the three methods of UV mutagenesis, microwave mutagenesis, chemical reagents mutagenesis mutagenesis, producing the highest enzyme activity obtained by microwave mutagenesis mutant was eventually screened for the next test strain measured obtaining enzyme activity 15.61U/mL, and enzyme activity compared with the original strain increased 78.20%. 3. Of Induced Strain the study of the Aspergillus niger inulinase conditions, to establish Aspergillus niger inulinase conditions in the optimal process parameters, test select the amount of wheat bran, the inulin add the amount of the added amount of peptone, yeast extract added fermentation time, temperature, pH, inoculum size, and other relevant factors, first screened through Plackett-Burmen trial design three significant factors: the amount of bran (P = 0.027741), fermentation time (P = .029919), the pH value (P = 0.012346). Then through the Box-Behnken experimental design of three significant factors for response surface optimization and build and analyze a mathematical model of the major impact factor of Aspergillus niger enzyme relationship. The test results show that the regression equation p = 0.0001 <0.01, the coefficient of determination R ~ 2 99.62%, indicating a good fit of the model with the experimental values. Aspergillus niger enzyme activity optimization process for 4.64% of the amount of wheat bran, fermentation time 81.5h, pH value of 6.0. This process parameters, strains producing enzyme activity reached 20.42U/mL. Compared with unoptimized strains enzyme production activity from 15.61 U / mL increased to 20.42 U / mL, 30.81%.
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