Extraction And Purification Of Inulin From Jerusalem Artichoke And Biological Activity Study

In this paper,Jerusalem artichoke as the trial materials.60℃hot air seasoning was selected as the pretreatment method of the Jerusalem artichoke.The ingredient of both red skin and white skin Jerusalem artichoke were analysed.Extraction process of inulin from Jerusalem artichoke has been studied.The optimum conditions of hot water lixiviating:times 70 mins,temperature70℃,solid to liquid ratio 1:30.The optimum conditions of ultrasonic extraction:ultrasonic power at 112W,temperature 70℃,times 20mins,solid to liquid ratio 1:20.The optimum conditions of microwave extraction:solid to liquid ratio 1:20,times 14mins, microwave power at 100 W.Crude inulin extracting solution was purified by lime,ethanol and amberlyst S-8. We can obtain high-purity inulin after vacuum freeze drying,and its purity is 96.2% which was determined by enzyme-HPLC method.The determined method of inulin molecular weight by HPLC was founded,the condition of chromatogram,mobile fhase is three-braize-water,velocity of flow is 0.8 mL/min;sample size is 20μL;shromatographic is OHpak SB-804;column temperature 30℃.The molecular weight of inulin which was extracted by different method was unlike.Hot reflux extraction 3500,ultrasonic extract 2405,microwave extract 3864.The culture condition of internally tangent inulase which was ferment by Aspergillus phoenicis was determined.The ingredient of culture medium was inulin 2%,NH₄H₂PO₄ 0.5%,KH₂PO₄ 0.25%,MgSO₄·7H₂O 0.05%,fermentation time 60h, fermert pemperature 28℃,initial pH 6.0～7.0,inoculum size 8%,the enzyme live of the grossly enzyme solution was 18.39U/mL and the I/S was 45.71.The condition of inulin enzymolysis:enzymolysis temperature 60℃～70℃, enzymolysis time 12～16h,substrate content 10%～20%,optimum pH 6.0～.0.The enzymolysis rate of inulin as high as 59.3%.We can obtain high-purity oligomerization levulose using ultrafilter device,and its molecular weight is 509 which was determined by HPLC.The Bifitdobacterium longum cultured in the culture which carbon source was inulin and oligomerization levulose was better than the Bifitdobacterium longum cultured in the culture which carbon source was glucose.It means that inulin and oligomerization levulose can work as growth factor of Bifitdobacterium longum.