Isolation And Characterization Of The Scutellaria Baicalensis Proteins

Scutellaria baicalensis herbs with a wide range of pharmacological effects, which is one of traditional Chinese medicine in China.The active ingredients of scutellaria baicalensis have been extensively studied. The extraction and epplication of flavonoids had a more comprehensive study. This study was carried out to broaden the use of Scutellaria baicalensis as well as to discover its new effctive components. In this paper the separation of scutellaria baicalensis proteins was studied and two-dimensional pure protein components were obtained and respectively characterized.Through the ammonium sulfate fractionation and several steps of ion exchange chromatography, a pure protein was obtained from the extraction of scutellaria baicalensis.The protein was referred to as Pro-1 protein. The protein was a kind of glycoprotein with sugar content of 14%, single-chain protein, intrachain disulfide in molecular structure and molecular weight of 62.23kDa by SDS-PAGE. Eight amino acid residues of Pro-1 protein N-terminal were GSAVGFLY. Pro-1 exhibited lectin activity and its ability to agglutinate was selective. It could agglutinate red blood cells in human and cock, but could not agglutinate red blood cells in mice and rabbits.By characterizing the Pro-1 protein, the results were showed. The lectin protein Pro-1 were stable in a wide range of pH,which were from 4.0 to 10.0. The lectin activity of Pro-1 protein had a poor thermal stability.When the temperature was over 60℃, the hemagglutinating activity decreased significantly. The Pro-1 protein was a metal-dependent type lectin, depending on Ca2+ and Zn2+. Pro-1 protein significantly inhibited tomato Fusarium oxysporum and Water hyacinth tenuis. It did not inhibit the E. coli and Staphylococcus. It obviously promoted the proliferation of normal liver cells L02, but it had not obvious effect on the proliferation of MDCK. Pro-1 protein significantly inhibited the growth of HepG2 cells with maximal inhibition rate of 83.43%.Another protein were obtained by two ion exchange chromatography. This protein was referred to as Pro-2 protein. With sugar content of 14%, the protein was a kind of single-chain protein, which had intrachain disulfides in molecular structure and molecular weight of 33.8kDa. The highest content was serine in the purified protein, which was 14.6%.The content of tyrosine and cystine were very low. Pro-2 protein could promote the growth of L02 (normal liver cells) with maximal inhibition rate of 83.23%. Within the concentration range of 1.72-110μg/ml, it was very toxicant for MDCK (normal canine kidney epithelial cells).It had slightly inhibited HepG2 cells with maximal inhibition rate of 17.15%.