1998/10/01 by Burkhard Becker, Michael Melkonian, Johannis P. Kamerling · 11 citations
Energy · Materials Science · Agricultural and Biological Sciences · #Algal biology and biofuel production #Diatoms and Algae Research #Seaweed-derived Bioactive Compounds
paper · doi:10.1046/j.1529-8817.1998.340779.x
Isolated cell walls (thecae) from the scaly flagellate green alga Tetraselmis striata Butcher contain the unusual 2‐keto‐sugar acids 3‐deoxy‐manno‐2‐octulosonic acid (Kdo), 3‐deoxy‐5‐O‐methyl‐manno‐2‐octulosonic acid (5OMeKdo), and 3‐deoxy‐lyxo‐2‐heptulosaric acid (Dha). In addition, galacturonic acid, galactose, gulose, and arabinose are present. EDTA‐extraction yielded an insoluble fraction that retains the shape of the cell walls and contains no 2‐keto‐sugar acids. Methylation analysis demonstrated the presence of terminal hexose, GalA, Dha, and Kdo as well as 2‐substituted hexose, 4‐or 8‐substituted Kdo, and 4,8‐disubstituted Kdo. However, most of the carbohydrate material (about 60%) was not methylated. Periodate oxidation of the cell wall preparation showed the presence of 2‐substituted Gul, 4‐ or/and 5‐substituted and 7‐ or/and 8‐substituted Kdo, which is in agreement with the methylation analysis. Again, a significant amount of carbohydrate material was not degraded, indicating complex substitution patterns. Oligosaccharides were generated by partial hydrolysis and fractionated using gel permeation chromatography and high‐pH anion‐exchange chromatography. Oligosaccharides contained either GalA and Kdo, or Gal, Kdo, Dha, and Gul, respectively. The structure of a GalA and Kdo containing disaccharide was established using 1 H NMR spectroscopy.