The Study On Isolution And Initial Determination Of Goat Placenta Peptides And It's Activity On Nutrition, Immune And Anti-oxidation

In 1985,Liu Yuexin reported that placental peptides was extracted by"homogenized-dialysis"for the first time.Then majority of researchers have done a lot of studies on placental peptides physicochemical properties and biological activity,found in the clinical treatment of viral hepatitis,neutropenia,myasthenia gravis and other autoimmune diseases and malignancy,there are more desired effect.The structure and function of placenta between goat and human have many similarities.In recent years it has been reported peptides can also be extracted from goat placenta .It has similar biological activity with peptides extracted from goat placenta,but the study on its biological activity is not comprehensive and on its active component is least.Because of the limited sources of goat placenta,it will have to be made through genetic engineering,and the study on activity component is the base. In this study goat placenta peptides obtained by ultrafiltration,initial isolation and identification through chromatography and electrophoresis.We analysised of nutrition components of crude extracts and studied of immune and antioxidant function of crude extracts and components isolated.So we wound found goat placenta peptides effect in nutrition,immune and antioxidant and provide reference for further study of the active component.The study is as follows:1. Isolution and initial determination of goat placenta peptidesThe frozen goat placenta defrosts at normal temperature,with the physiological saline flushing.Take cotyledons, cut into small fragments. These cotyledons after repeatedly frozen-thawed three times were pounded to pieces for 3min at 12000 rpm,10times, in high speed tissues pounding homogenizer high speed, and then homogenate was centrifuged for 20min at 8000 rpm at 4℃high speed refrigerated centrifuge. The supernatant collected after precipitation were filtered with 0.45μm and 0.22μm screen mesh in order to remove the insoluble materials, and finally ultrafiltrated with YM—10 Centrifugal Filter Units to obtain the crude extract of goat placenta peptides.It is colorless transparent liquid and can be dialysised and ultrafiltrated.It is non-pyrogen's and its pH is 6.6~6.9. After the superdex75 chromatographic analysis, obtain four peptides components namedⅠ,Ⅱ,Ⅲ,Ⅳ.After freeze-drying,all are white powder.Their molecular weight are 10.139KDa,8.166KDa,7.447KDa,6.761KDa ,which were determined through added urea and glycerine Tricine-SDS-PAGE.2. Detect amino acid and mineral elements in goat placeta peptidesIn extracts of the goat placenta peptides,17 amino acid were detected ,in which 7 essential amino acids,which is 34.36% of total amino acid.It has 9 essential amino acids for children(His and Arg are essential amino acids for children),which is 42.59% of total amino acid.In extracts of goat placenta peptides,trace elements Fe,Zn,Cu,etc were detected,heavy metal were hardly detected.The threat of heavy metal poisoning can not appear in clinical use.So,the goat placenta peptides has high nutritional value and is safe and ideal amino acid supplement nutrition.3. Immune function of goat placenta peptides on miceThe mice were randomly divided into 6 groups,5 groups for experimental group(distinction abdominal cavity injection component:Ⅰ,Ⅱ,Ⅲ,Ⅳand crude extract).Each experimental group were injected with three dose (18mg/kg,9mg/kg,4.5mg/kg),10 per group ,the control group (10 rats) injected only with saline.Injected once one day for a week. The detection of IL-2 in peripheral blood serum showed that all the components test groups increased it compared with the control group,Ⅲ,Ⅳand crude extract group increased 15.3%-30.1%,significant difference(p<0.05),activity of componentⅣis highes,but have no significant difference compared withⅢand crude extract group(P>0.05). The detection of mouse peritoneal macrophage phagocytosis showed thatⅢ,Ⅳand crude extract group increased it compared with the control group, significant difference(p<0.01).The two tests show that goat placenta peptides have immune inhance function,in which active components areⅢandⅣ.4. Anti-oxidation activity of goat placenta peptides on miceThe detection of the level of SOD,MDA showed that medium and high doseⅣand crude extract groups can promote the level of SOD and SOD/MDA (P<0.05) and depress the level of MDA(P<0.05).High dose group appeared obviously,but had no significant difference (p<0.01)group.The most obvious group was crude extract group,but there is no difference compared withⅣgroup(P>0.05).The reason of activity ofⅣlower than crude extract might be the loss in separation process.The active component is componentⅣin crude extract..