Studies On Seperation, Purification And Structure As Well As Bio-activities Of Phycoerthyrin From Nostoc Sphaeroids Kutz

The significant biological and pharmacological activity of Nostoc Sphaeroids kutz with abound nutrition and infrequent distribution had been paid people's much attention. Although NSK as a kind of food and medicine function had been used for several thousand years, the main active component of activity and function is little investigated. In recent years, it was by a few people that its partial physiology and primary biochemistry composition was reported. In order to ascertain the active component of NSK, the phycobiliproteins was used as material. Relationships between its bioactivity and its conformation were attempted to discovery, on the basis of systemically studies on preparation and purification of NSPE by using modern separation technology and modern chemical analysis method. The main results were shown as follows:1 The ecological conditions and distribution for NSK and its biochemisty componentOn the basis of the ecological conditions for NSK and their analysis having been investigated, in order to determine its biochemistry components, such as water, protein, fat, polysaccharide, carotene and chlorophyll as well as mineral element, wild NSK, Zouma town, Hefeng county, Hubei province, was used as crude material.2 Extraction, separation, purification and identification of NSPEDefatted NSK as material, albumin, globin and salt-soluble protein were separated from NSK by salting-in and salting-out methods for the first time and the the optimal extraction technology were studied. The results were as follows: pH 7.0, salt concentration 0.2 mol/L and extracted time was 4 h, and the output of phycobiliproteins was 7.13 percent. DEAE-Cellulose ion-exchange chromatography was used to separation NSPP. It wassuccessful to obtain five fractions, by the step gradient. PE was further purified by DEAE-Separose FF, HA and Sephadex G-25 chromatography. Some methods such as spectrophotometer and chromatography and electrophoresis were applied to identify the purity of PE, and it was identified to be chromatography and electrophoresis grade pure.3 The stability of NSPPThe effect of temperature, pH, light intensity, alcohol concentration, neutral salt concentration and sucrose concentration on the stability of NSPP was investigated. The results showed that, NSPP kept still stability under the appropriate circumstance: under natural sunlight, below 40°C, pH 5-8, alcohol concentration < 40°.4 The structure characterization of NSPPThe molecular weight (MW) of PE was measured by non-denaturing polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), the results demonstrated that the MW of PE is 51.808kd; As the result of circular dichroism (CD) spectrum and Fourier transformation infared (FTIR) spectrum shown, the secondary structure of PE was mainlya-helix t and the content of B-shee or coil was very small; PE's agglutination form was observed by force atom microscope (AFM), there were mainly different size globular form. Meanwhile, its denatured temperature was also studied by differential scan calorimeter (DSC), the results showed that the temperatute was 56.1°C.5 Antioxidant activity of NSPEScavenge capability of oxygen free radical was studied by chemiluminescence, the results showed that scavenge capability was orderly, H2O2 radical, -OH radical, O2~' radical, respectively.