The Yacon The Carbohydrate Component Analysis And The Fructooligosaccharides Preparation Process Route Preliminary

Yacon (Smallanthus sonchifolius [Poepp. & Endl.] H. Robinson) is a member of the Asteraceae and is an under- exploited native tuber crop which constitutes part of the diet of Indian tribes living in the high mountain areas of the Andes.Yacon stores oligofructans (fructo-,oligo-saccharides, FOS) as its main component of dry matter (DM) and is commonly consumed by people suffering from diabetes or from various digestive or renal disorders. Recently,yacon has been successfully introduced in Yun Nan Province.In this reserch,suger components were identified by high performance thin layer chromatography(HPTLC) and liquid chromatography-mass spectrometry (LC-MS). The suger components in yacon were determined using phenol-H2SO4 method and detected by UV detector.High performance liquid chromatography- differential refractive index detector(HPLC-RID) was used for the assay of suger components in yacon.At last a pragmatic method had been established to produce coarse yacon oligofructans via several procedures.In the first part,HPTLC and LC-MS were used for the identification of eleven suger components including fructose,glucose,sucrose,GF2~GF9 in yacon.We used high performance silica gel plate,the mobile phase was acetic acid-chloroform- dried ethanol-water(9:11:11:2,v/v), used amino benzene-phenylene diamine- phosphoric acid as chromogenic agent; Agilent LC - MSD Trap XCT Plus system and the mobile phase acetonitrile-10mM aqueous ammonium acetate(60:40,v/v) was used, Chromatography was performed at a constant temperature of 40℃on a UltimateTMXB-NH2 column for LC-MS detection.The result indicated that most suger components were well separated.In the second part, the suger components in yacon were determined using phenol-H2SO4 method.Oligosaccharides are hydrolyzed in H2SO4 into mono- saccharides,then quickly dehydrate and produce an orange-yellow color under the interaction with phenol,this solution has an especial absorption at 490nm.A fine linear correlation was get from 0.04mg to 0.24mg in the experiment. UltimateTM XB-NH2(5μm,4.6mm×250mm)column and Waters R401 differential refractive index detector were used in HPLC method. Chromatography was performed at 35℃, we used acetonitrile-water(85:15,v/v)for the monosaccharides ( fructose , glucose ) separation and acetonitrile - water ( 70:30 , v/v ) for the oligosaccharides (sucrose,1-kestose,nystose,1F- Fructofuranosylnystose) separation, six regression equations were acquired for quantitative determination,the six kind of suger components had a well liner correlation in the range of 0.9~16.2mg/mL(fructose),0.6~10.8mg/mL(glucose), 0.6mg/mL~ 8mg/mL (sucrose), 0.45~6mg/mL(1-kestose, nystose) and 0.27~ 3.6mg/mL (1F-Fructofuranosylnystose) separately. The experiment also examined the two main influencing factors:organic solvent ratio of the mobile phase and the column temperature. We also figured out the DM ratio in the fresh yacon tubers in this part.In the last part, Using chitosan as flocculant tranference of saccharide and transmittance at 680nm as two indexes,we examined the effect of flocculation of chitosan in yacon extracts and figured out the tranference of the six saccharides separately. The coarse yacon oligofructans we produced contained more than 20% oligofuctans (GF2~GF4).