An acidic polysaccharide with xylose branches from Porphyra yezoensis  

作　　者：ZHANG Weiyun CHEN Hao WANG Shuijuan XIA Zhonghao FEI Xiugeng TAN Renxiang 

机构地区：[1]Institute of Functional Biomolecules,State Key Laboratory of Pharmaceutical Biotechnology,School of Life Sciences,Nanjing University,Nanjing 210093,China [2]Experimental Marine Biology Laboratory,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China

出　　处：《Chinese Science Bulletin》2001年第3期207-210,共4页

基　　金：This work was supported by the National Natural Science Foundation of China (Grant Nos. 39725033 and 39970083);and also by the Research Fund for the Doctoral Program of Higher Education (Grant No. 1999028419).

摘　　要：An acidic polysaccharide (PY3) was isolated from the hot water extract of the red algae Porphyra yezoensis by successive column chromatographies over DEAE-cellulose and Sephadex G-200. PY3 with an average molecular weight of 1.8×105 was demonstrated to be composed of galactose (Gal), 3,6-anhydrogalactose (3,6-AnGal), 6-OSO3-galactose (6-OSO3-Gal) and xylose (Xyl) in an approximate molar ratio of 25:15:10:1. In view of Smith degradation and me-thylation and on the basis of spectral evidence including those of IR, GC, GC-MS, and 1H and 13C NMR, the most probable repeating unit of PY3 could be proposed as [(1-3)β-D-Gal(1- 4)α-L-3,6-AnGal]3-[1-3)β-D-Gal(1-4)α-L-6-OSO3-Gal]2 with a xylose moiety at the C6 of one of every twenty-five β-D-Gal residues. To our knowledge, PY3 was shown to be the first porphyran possessing occasional xylose branches.An acidic polysaccharide (PY3) was isolated from the hot water extract of the red algaePorphyra yezoensis by successive column chromatographies over DEAE-cellulose and Sephadex G-200. PY3 with an average molecular weight of 1.8×105 was demonstrated to be composed of galactose (Gal), 3,6-anhydrogalactose (3,6-AnGal), 6-OSO3-galactose (6-OSO3-Gal) and xylose (Xyl) in an approximate molar ratio of 25: 15 : 10 : 1. In view of Smith degradation and methylation and on the basis of spectral evidence including those of IR, GC, GC-MS. and1H and13C NMR, the most probable repeating unit of PV3 could be proposed as [(1→ 3)β-D-Gal(1→4)α-L-3,6-AnGal]3-[(1→3)β-D-Gal(1→4)α-L6-OSO3-Gal]2 with a xylose moiety at the C6 of one of every twenty-five β-D-Gal residues. To our knowledge, PY3 was shown to be the first porphyran possessing occasional xylose branches.

关 键 词：PORPHYRA YEZOENSIS ACIDIC POLYSACCHARIDE structure elucidation. 

分 类 号：Q53[生物学—生物化学]