Isolation and characterization of the 337 mμ UV-absorbing substance in red alga, <italic>Porphyra yezoensis</italic> UEDA<xref ref-type="fn" rid="fn1"><sup>1</sup></xref>

Using a variety of Sephadex gel filtrations, starch block zone electrophoresis, Avicel SF preparative TLC and DEAE cellulose column chromatography, the characteristic 337 mμ UV-absorbing substance from marine red alga, Porphyra yezoensis UEDA was isolated. The molecular weight of this substance was about 1,000, and its chemical composition was 43.11% C, 5.85% H, 7.23% N, 34.73% O and 9.08% Na. In vivo it is located in the chloroplast. On irradiation at 378 mμ, it has a fluorescence action spectrum peak at 470 mμ. Structural studies on this substance are still underway, but it could be a kind of aminosugar judging from NMR, IR spectra and other chemical properties.