Study On Production Of Phosphorylated Oligosaccharides From Potato Starch

Phosphorylated oligosaccharides was a new kind of functional oligosaccharide by connecting glucose residue of oliosaccharde with phosphate radical together by covalent bond,was composed of maltotriose to maltohexaose, it had many characteristics,such as no dental caries and anti starch aging etc. among which the outstanding physiological functions were inhibiting formation of insoluble calcium phosphate and promoting absorption of calcareous.It was a new carbohydrate which was natural, safe and widely used.The concept of phosphorylated oligosaccharide was most early proposed by Japanese scholars named Kamasaka,H. in 1995. At present, commercial product of phosphorylated oligosaccharide had already occurred in the market in Japan,however, the attention of china to phosphorylated oligosaccharide is relative later, There were no study on production preparation of phosphorylated oligosaccharide, therefore, perfecting towards relevant theoretical research had important realistic meanings.Malt syrup oligosaccharide with lower DE value was prepared by fully enzymatic method and jet liquefaction process through taking potato starch as material. Composition of carbohydrate of prepared sample was determinated by HPAEC-PAD. Phosphorylated oligosaccharide was separated by Ion exchange resins,At last, Qualitative analysis was developed by thin layer chromatography(TLC) and HPAEC-PAD. Analysied the structure of POs by infrared spectroscopic method.The study of preparation technology provide a solid theoretical basis for implementation of industrial production of phosphorylated oligosaccharide.In the study, Malt syrup oligosaccharide with lower DE value was prepared by low-pressure injection liquefaction technology, concrete operation technologies were as follows:adding water to material-compound tank, slurry density was adjusted to 10 oBe after adding starch, subsequently,0.6~0.7 kg CaCl2 as enzyme activity accelerator was added, adjusting pH value of slurry to 5.4, Then newα-amylase of 100ml with high temperature resistance was added. Material was pumped into injection liquefier after stirring uniformly, The parameters of injection liquefier were: injection temperature of 110℃, time of 4~8 min, discharge temperature of 95~97℃, Adding solid to liquid after injection liquefaction to laminar flow tank,it was holded in 95℃for 30min, Enzyme was inactivated by steam when the color of Iodine test reaction presented natural color of iodine. Meanwhile, plate-frame pressure filtration was performed keeping initial pressure at lower than 0.6 MPa level, increased gradually pressure to not exceed 2 MPa with the increasing of formation resistance of filter cake, solid to liquid was cooled to 60℃,then was saccharified,Adding fungal amylase of 100 ml and pullulanuse of 50 ml to saccharification pot, pH value was adjusted to 5.2 for reaction of 2~4 h. Subsequently, Enzyme was inactivated in 100℃for 2~3h by high pressure steam. Sugar solution after saccharification entered into bleaching tank along the pipeline, pigment and someinorganic salt were striped down, activated carbon was removed using pressure filtration by allowing activated carbon entering plate and frame filter press together with sugar solution. Sugar composition of oligosaccharide syrup prepared was determined using HPAEC-PAD method, The results showed that:, The sample contained glucose, maltose to maltoheptaose, among which contents of glucose was lower and maltose to maltopentaose were higher, which explained oligosaccharide syrup, producted by above process, accorded with requirements of sugar component in the process of separation and preparation of phosphorylated oligosaccharide.Separation effects of D201,D315 and 201×4 on phosphorylated oligosaccharide were studied, The results showed that elutive rations were 65.4%,76.3% and 89.4%, respectively. separation effect of 201×4 on phosphorylated oligosaccharide was the best, By investigating the separation effect of eluent concentration and flow rate on phosphorylated oligosaccharide, The optimum elution conditions were as follows: after neutral sugar was eluted by deionized water ,eluting the POs by 0.4 mol/L NaCl at the speed of 1.4 mL/min, collect the eluent and tested by phenol-sulferic acid method.POs was analysied by TLC and HPAEC-PAD method.The results showed that POs was maltooligosaccharides which conbined with phosphate group,and it's DP range was 2~7, maltotriose, maltotetraose,maltopentaose and maltohexaose were the most of the components. Analysied the unit structure of POs by infrared spectroscopic method.The analysis results showed that the material was a kind of oligosaccharides which binding phosphate, named phosphorylated oligosaccharide.