Studies On Extraction And Analysis Of Fructooligosaccharides In Smallanthus Sonchifolius

Yacon,a root crop rich in fructo-oligosaccharides(FOS),is the material of our research.We commit ourselves to the study of the extracting of water bath,flocculation,deproteinizing,depositing in alcohol and decoloring of FOS.Moreover,we also pay some attention to the quantitative analysis and qualitative analysis of FOS.The terms as follows:In the first part,the extraction of the FOS from yacon with water bath system was studied.Ascorbic acid was utilized to the color protection of yacon mashed fruit,and analyze the quantity of color fixative,the best conditions is:the concentration of color fixative is 0.3% and the ratio of color fixative to yacon solution is 1:3.The single factor and orthogonal experiment was studied to the temperature of water bath,time and the ratio of solid to liquid.The optimum extraction condiions are that the temperature of extraction is 72℃,the ratio of solid to liquid is 1:15 and the time of extraction is 3h.Under the above conditions, the average extraction rate of yacon FOS is 56.5%.In the second part,Preliminary separation and purification of the water-soluble FOS in yacon was researched.Floccular purification by CPAM was carried out depending on its charge-neutralization and bridging action, four factors of CPAM were tested ,there are the quantity of CPAM,pH of flocculation,time of flocculation,temperature of flocculation.The best conditions after orthogonal test are that the quantity is 0.08%,pH is 6,the time is 3h,the temperature is 52℃.Then deproteinizing was studied by sevag and the quantitative analysis and qualitative analysis of protein were undertaked,the regression equation of the concentration of protein(c) and absorbance(y) is Y=0.041X+0.0043,R=0.998.The absorption peak of protein can be seen at 280nm before deproteinizing.After that,the polysaccharose was deposited in alcohol and FOS was separated from solution,the FOS crude product was got and its percentage composition is 56.2%. In the third part,Four types of resins were tested to determine the best one in decolorizing Yacon FOS,they are D941,D318,DM-2,860021.Four factors were ascertained in the static absorption experiments,which are that the time of decolorizing is 3h,temperature of decolorizing is 52℃,the quantity of resin is 3.7% and the pH is 5.2.In the optimum conditions,several yacon extracting solution were tseted,their one-off light transmittance in average is 90.4%.In the last part,the quantitative analysis and qualitative analysis of FOS were undertaked.The total suger content in yacon were determined using phenol-H2SO4 method.The standard curve of total suger is:Y=0.0036X-0.0317,R=0.999.The reducing sugar content in yacon were determined using DNS colorimetry.The standard curve of reducing suger is:Y=0.7787X-0.0564,R=0.999.The total suger content minus the reducing sugar content equals the content of FOS in yacon.HPTLC by silica gel plate were used for the identification of suger components including fructose,glucose,sucrose,FOS in yacon.The mobile phase was acetic acid-chloroform-dried ethanol-water,which can separate kinds of sugar well,and all kinds of saccharides—glucose,sucrose, and FOS in yacon samples were detected by HPLC.