The Effects Of γ-poly-glutamic Acid On Iron And Calcium Absorption And Assessment Its Toxicology And Safety

The purpose of this study was to research the effects of 100 kDa y-poly-glutamic acid(y-PGA) on iron and calcium absorption and assess its toxicology and safety. It mainly includes three parts:1. The purpose of this study was to research the effect of y-PGA on iron absorption in Wistar male rats. All rats were fed low-Fe diets for 3 weeks to induce Fe deficiency anemia. The venous blood was collected to measure the Hb,the rats which Hb was less than 90g/L were successful animal mold. Thirty Wistar rats were randomly divided into three groups, with 10 replications per group. The supplemental levels of y-PGA were 0.1% or 0.2% respectively. The trial period was 3 weeks. The results of this study showed body weight was no significant differences between the treatment group and the control group at the end of the experiments (P>0.05). The femur relative weight of 0.1%γ-PGA group was significantly higher than the control group(P>0.01),the liver relative weight of 0.2%γ-PGA group was significantly higher than the control group(P>0.01),and spleen relative weight of 0.1% or 0.2%γ-PGA group was significantly higher than the control group (P>0.05). Hemoglobin, red blood cell count and hematocrit were no significant differences between y-PGA groups and control group there (P>0.05),the serum iron concentration of 0.1% or 0.2%γ-PGA groups was significantly higher than the control (P<0.01). The serum total iron-binding capacity of 0.2% PGA group was significantly higher than 0.1% PGA group and the control (P<0.01). The liver iron, spleen iron and femur iron concentration of 0.2% PGA group was significant higher than the control (P<0.01).Conclution:y-PGA can promote iron absorption.2. The purpose of this study was to research the effects of y-PGA on calciun absorption in Wistar male rats. The rats were fed low-Ca diets for 3 weeks to induce Ca deficiency, then, serum CT level was detected to evaluate Ca deficiency model. Thirty Wistar rats were randomly divided into three groups, with 10 replications per group.Three supplemental levels of y-PGA were 0.01%,0.05% or 0.1% respectively, the level of CPP was 0.1%,the trial period was 3 weeks. The results of this study showed that the daily gain of 0.1% CPP and 0.05%γ-PGA group was significantly higher than the control group(P<0.05); The femur Ca concentration of 0.1%γ-PGA group was significantly higher than the control group (P<0.05), and the femur phosphorus concentration of 0.1%γ-PGA group was significantly higher than the control group (P<0.01); The serum bone alkaline phosphatase (BALP) of all y-PGA group was significantly higher than the control group (P<0.01). Conclution:y-PGA can increase femur calcium and phosphorus concentration and promote the femur growth.3. The purpose of this research is to assess toxicology and safety of y-PGA. The experiments include acute toxicity test, mice sperm abnormality test, bone marrow cells micronucleus test, the Ames test and thirty days feeding study. The results suggested that the maximum tolerance dose of y-PGA to mice is more than 1.5g/kg·bw, so it was a kind of nonpoisonous substance according to the grading standards of acute toxicity of chemical substance. The results of sperm aberration test and bone marrow cells micronucleus test both showing negative; there are all negative of the TA97, TA98, TA100 and TA102 strains in Ames test whenever S-9 activation or not.The results of 30 days feeding study in female showed that body weight gain of 1.0g/kg·bw and 1.5g/kg·bwγ-PGA group are significantly lower than the control group (P<0.05),the rate of feeds conversion,liver weight,spleen weight,and kidney weight of 1.5g/kg-bw y-PGA group are significantly lower than the control group(P<0.01), the kindey relative weight of experiments group is significantly higher than the control group(P<0.01). The number of neutrophils of 1.5g/kg·bwγ-PGA group are significantly higher than the control group(P<0.01), serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) of 1.5g/kg-bw y-PGA group are significantly higher than the control group(P<0.01), triglycerides of 0.5g/kg·bw and 1.5g/kg·bw y-PGA group are significantly lower than the control group (P<0.05).The results of 30 days feeding study in male showed that body weight gain and the rate of feeds conversion of experiments group are significantly lower than the control group (P<0.01); Liver weight of 1.0g/kg-bw y-PGA group is significantly lower than the control group(P<0.01), spleen weight, kidney weight and testicular weight of 1.5g/kg-bw y-PGA group are significantly lower than the control group(P<0.01), liver relative weight of 0.5g/kg-bw and 1.0g/kg-bw is significantly higher than the control group(P<0.01), the kindey and testicular relative weight of experiments group are significantly higher than the control group(P<0.01); The number of neutrophils and intermediate cell of 0.5g/kg·bw and 1.0g/kg·bw are significantly lower than the control group(P<0.01), ALT of experiments group y-PGA group are significantly higher than the control group (P<0.01), creatinine(Cr) and white blood cell(WBT) of experiments group y-PGA group are significantly higher than the control group (P<0.05), serum urea nitrogen of 1.5g/kg-bw group is significantly higher than the control group (P<0.01).Conclution:γ-polyglutamic acid is safe,but when the dose is more than 0.5g/kg·bw for a long-term can damage spleen and liver.