The Preparation And Iron Bioavailability Evaluation Of Tea Polysaccharide Iron Complex

China is a country with a high incidence of iron-deficiency anemia. The incidence rate has reached 15-20 percent, and more than 20 percent of the nation's women and children suffer from the disease. Anemia has seriously affected people's health. Ferrous sulfate is the traditional medication to cure anemia which may cause toxic side effects included diarrhea, nausea, vomiting. Polysaccharide iron complex(PIC) is a new kind of iron supplement prepartion which use polysaccharide as the ligand. PIC has steady highly water-solubility, has no dissociate iron ion in the solution , can be absorbed in the form of undissociated molecules , and the iron bioavailability is higher than ferrous sulfate. The polysaccharides ligand have many bioactivities. So there are more and more research on the PIC now.In the first part of the study crude tea polysaccharides(27%) are purified by ethanol precipitation and PVPP adsorbtion methods. The polysaccharide,polyphenol and protein content of the product are 67% , 0.7%, 6.7% respectively.Then the tea polysaccharides and iron complex(TPS-Fe) are prepared use ferric chloride and purified tea polysaccharides as raw material. The optimum reaction conditions(pH value, temperature, reaction time, material ratio) are obtained by orthogonal experiment. The result shows that pH value is the most effective factor on iron content, followed by temperature and material ratio, the reaction time has the minimum impact. The best reaction condition is that pH 8, 60℃, material ratio is 0.5g:1.2g, reaction time 1~3 h. The iron content of the complex made under the optimum reaction conditions is 14.6% . Qualitative identification, iron dissolution, moisture absorption and moisture retention experiment of TPS-Fe are carried out in the part two of the paper. Result showes that there are not dissociate iron ion exist in the product and iron ion can dissociated after be reduced 2 hours by vitamin C. TPS-Fe should be sealed preservation because of its easily moisture absorption property.In vitro digestion and dialysis method and rat hemoglobin repletion bioassay are carried out to evaluate the iron bioavailability of TPS-Fe ,use ferrous sulfate as positive control. In the rat test, anemia model rats are gastric perfusion two kinds of solutions- TPS-Fe and ferrous sulfate. Each solution has 4 doses (iron content: 12, 24, 36, 48 mgFe/kg.diet respectively).Result showes that after gastric perfusion all the treatment groups'rats were resumed gradually ,and there exists a linear relationship between the restoration effects and gastric perfusion dose(12,24,36 mgFe/kg.diet). The effects of 36 and 48 dose of the two samples are nearly the same. Generally, the iron bioavailability of TPS-Fe is 102~114 compared with ferrous sulfate whose iron bioavailability is 100 when we use some items in blood to evaluate. The activity of anti-oxidation enzyme in blood and liver homogenate of TPS-Fe treatment groups are increased significantly compared with ferrous sulfate treatment groups. Therefore TPS-Fe is a very potential iron additive.