Characterization of polysaccharides from Enteromorpha intestinalis (L.) link, chlorophyta

Cell-wall mucilaginous polysaccharides from Enteromorpha intestinalis were extracted, purified and their physicochemical characteristics determined. The successive extracts, obtained using distilled water at 35°C, distilled water at 75°C then an aqueous solution (0·25%) of ammonium oxalate at 75°C, all contained a sulphated glucoglucuronoxylorhamnan containing about 43% rhamnose, 19·8% sulphate and 17% uronic acid (based on the dry weight of the extracts). This composition is comparable to reported values for other Ulvaceae. However, the successive extracts differ in osidic composition and physical properties. In particular, extracts using oxalate at 75°C contain galactose and have lower values of viscosity and molecular weight with respect to those obtained in the first and second extracts, probably as a result of the breakage of labile interchain bonds during extraction.