Preparation of Polysaccharide from Porphyra yezoensis Ueda and Its Effects on Growth of Lymphocytes

The purified polysaccharide PY2 was obtained by DEAE-cellulose and Sephadex G-200 column chromatography from Porphyra yezoensis . The average molecular weight was determined to be 2.0×10⁴ by using column chromatography. PY2 was also identified by UVand IRspectra. The results showed that PY2 is a kind of infrequent polysaccharide from Porphyra ,which could inhibit the proliferation of murine spleen cells, thymus cells and mixed lymphocyte reaction. There were no distinct effects of PY2 on bone marrow cells.