Study On Preparation And Separation Of Phosphoryl Oligosaccharides

Phosphorylated oligosaccharides （Pos） is a kind of new functional oligosaccharide,which refers to the malto oligosaccharide within covalently-bound phosphate groups （C-o-galloylhyperin P） linked to the glucose residues, and the degree of polymerization isbetween3⁶. As a new oligosaccharides of special functions,Pos was found in ahydrolysis research of potato starch by a Japanese scholars Kamasaka, H, during the1990s,and then a further study was carried on. Pos has more than the functionalcharacteristics of general oligosaccharides, it also can inhibit the formation of insolublecalcium salt in vivo, thus to promot calcium absorption and dissolve, still to strengthen theremineralization of tooth enamel, and that can prevent caries, at the same time Pos has anaging resistance effect of starch, and with no undesirable flavor or taste, can be widelyused in food, medicine, health care and feed additive industries.This topic studied the preparation methods of a Pos precursor-low DE value of maltooligosaccharide, and potato starch was used as raw materials, the liquefaction andsaccharification processing were carried out by full enzymatic method. Considering theinfluence on DE value of the major factors in preparation process,such as pH, enzymedosage, saccharification time and temperature by single factor experiment, then orthogonaltest was designed to optimize the preparation technology.The best production conditionsfor low DE value malto oligosaccharide were:20%of starch, pH6.1,10μLof hightemperature resistant a-amylase,1.0μL of fungal enzyme dosage,1.0μl of Pullulanasedosage, the temperature of saccharification was60℃,the time was120min. The DE valuewas controled within30%⁴0%in the optimized preparation process, the yield of maltooligosaccharide was higher as well, so as to build a good preparation and extractfoundation of for POS.A method of isolation and purification by anion exchange resin for Pos was adopted inthis research, and the elutive rations of Pos with5kinds of anion exchange resin—D201，7170，D315，AB-8，201×4were inspected. The best filler to isolate and purify Pos waschoosed after considering the adsorption and resolution rate through the static adsorptionexperiment, which was7170Strongly basic styrene anion exchange resin; and processingconditions were established after the optimization of eluant concentration and elutionvelocity,which were: elute neutral sugars with deionized water, then elute Pos with0.1mol/LNaCl acetic acid-sodium acetate buffer, at the eluate speed of1.5mL/min. To apply the methods of thin-layer chromatography and HPAEC—PAD oncomposition analysis to Pos, the results show that with the developing solvent of n-butanol:acetic: water=3:1:1, and the chromogenic agent of aniline-diphenylamine—phosphoricacid solution, the component from maltose to maltoheptaoseas were effectively seperated,every point in silicon sheet spreaded out relatively well and also showed a goodcolor-reaction. In combination with HPAEC-PAD and ir bromide tabletting method forfurther composition and structure analysis, results suggested that the P-O-C groups of Poshad vibration absorption peaks in1080cm^-1, and pentavalent phosphorus had P-O stretchvibration peaks in928cm^-1.Further more, it makes sure that Pos was a kind of maltooligosaccharide mixture which was combined with the phosphate group and had a degreeof polymerization of2⁷.The pilot-plant preparation process of Pos was also designed in this topic, the mainprocess included: injection liquefaction process, saccharification process, anion exchangeisolation process and enrichment process, and flow diagram the these main processes weredesigned in this paper. Meanwhile, the previous study of the pilot-plant equipments andindustrialization was carried through, which made the preparation of Pos economicllyfeasible, and based directly for its industrial production.