Determination of Polysaccharides Content in Alpinia Oxyphylla

OBJECTIVE To establish a method for content determination of polysaccharides in Alpinia oxyphylla. METHODS The crude polysaccharides were extracted by hot water and precipitated with ethanol. The purified polysaccharide was obtained by removing protein and colors with Sevage and H₂O₂, repectively, then run water dialysis and frozen-drying. The monosaccharide composition was determined by HPLC after precolum-derivatization with 1-phenyl-3-methyl-5-pyrazolone (PMP). The conversion coefficient of Alpinia oxyphylla polysaccharides to glucose was obtained by refined polysaccharides, and then the content of crude polysaccharides in Alpinia oxyphylla was determined by sulfuric acid-phenol method. RESULTS The monosaccharide compositions in polysaccharides from Alpinia oxyphylla were Glu, Rha, Gal, Man, and Ara. The content of polysaccharides was 12.91%(RSD=4.72%, n=5), and the average recovery was 99.1% with RSD of 4.57%(n=5). CONCLUSION The method is sample, and can be used for determination of the content of polysaccharides from Alpinia oxyphylla.