Abstract: Provided is a modified rice endosperm-specific promoter, which has a sequence as shown in any one of SEQ ID. NOs. 1 to 5. The EnhGt13? promoter as shown in SEQ ID NO. 2 drives GUS activity in vitro and mediates the expression of foreign proteins in rice endosperm cells, which is significantly higher than that of the unmodified Gt13? promoter. The promoter can be applied to the fields of improving seed quality, molecular pharming, etc.

Abstract: Disclosed is a chromatographic method for isolating and purifying high-purity recombined human serum albumin, comprising: conducting cation-exchange chromatography on recombined human serum albumin, and adding alcohol to a buffer solution to remove endotoxin, so as to obtain a primary product I; under binding conditions, conducting anion/hydrophobic composite resin exchange chromatography on the primary product I to obtain an intermediate product II; conducting hydrophobic chromatography on the intermediate product II to obtain the target product, the purified high-purity recombined human serum albumin. The purity of the recombined human serum albumin obtained by isolating and purifying with the chromatographic method of the present invention is greater than 99.9999%, and the content of the endotoxin meets the criteria stipulated by Chinese pharmacopoeia.

Abstract: A method for extracting recombinant human serum albumin (rHSA) from transgenic rice grain is provided, comprising the steps of: 1) grinding dehusked rice containing rHSA into milled rice grain with a fineness of 80˜120 mesh, which is mixed with a extraction buffer in a w/v ratio of 1:5, then extracting at 55˜60° C. for 1˜3 hours to obtain mixture I; said extraction buffer comprises 10˜30 mM phosphate buffer, 10˜20 mM sodium acetate, 15˜30 mM ammonium sulfate and 5˜20 mM sodium caprylate and has a pH of 6.5˜8; 2) adjusting the pH of mixture I to 4.0˜4.5, followed by precipitating at room temperature for 3˜12 hours to obtain mixture II; 3) filtering the mixture II and collecting the filtrate, to obtain a solution containing high concentration of rHSA. The concentration of rHSA in the resultant solution is 650˜660 ?g/mL, which increases by 1.15 times comparing to the extraction amount before improvement, and the amount of non-target protein is reduced by 2.46 times.

Abstract: A method for extracting recombinant human serum albumin (rHSA) from transgenic rice grain is provided, comprising the steps of: 1) grinding dehusked rice containing rHSA into milled rice grain with a fineness of 80˜120 mesh, which is mixed with a extraction buffer in a wily ratio of 1:5, then extracting at 5560° C. for 1˜3 hours to obtain mixture 1; said extraction buffer comprises 10˜30 mM phosphate buffer, 10˜20 mM sodium acetate, 1530 mM ammonium sulfate and 5˜20 mM sodium caprylate and has a pH of 6.5˜8; 2) adjusting the pH of mixture I to 4.0˜4.5, followed by precipitating at room temperature for 3˜12 hours to obtain mixture 3) filtering the mixture 11 and collecting the filtrate, to obtain a solution containing high concentration of rHSA. The concentration of rHSA in the resultant solution is 650˜660 ?g/mL, which increases by 1.15 times comparing to the extraction amount before improvement, and the amount of non-target protein is reduced by 2.46 times.

Abstract: Disclosed is a chromatographic method for isolating and purifying high-purity recombined human serum albumin, comprising: conducting cation-exchange chromatography on recombined human serum albumin, and adding alcohol to a buffer solution to remove endotoxin, so as to obtain a primary product I; under binding conditions, conducting anion/hydrophobic composite resin exchange chromatography on the primary product I to obtain an intermediate product II; conducting hydrophobic chromatography on the intermediate product II to obtain the target product, the purified high-purity recombined human serum albumin. The purity of the recombined human serum albumin obtained by isolating and purifying with the chromatographic method of the present invention is greater than 99.9999%, and the content of the endotoxin meets the criteria stipulated by Chinese pharmacopoeia.