Resumen de Carbohydrates from the sequential extraction of lessonia vadosa (phaeophyta)

Nancy P. Chandia, Betty Matsuhiro, Johanna S. Ortiz, Andres Mansilla

• Blades of Lessonia vadosa were sequentially extracted with 70% ethanol, followed by 2% CaCl2 solution,, diluted HCl (pH 2), and finally with 2% Na2CO3 solution. D-mannitol was the only low molecular weight carbohydrate obtained from the ethanolic extract. By ion-exhange chromatography of the CaCl2 extract a fraction contaning 36.7% of sulfate group was obtained. Chemical and spectroscopic analysis indicated the presence of a regular polymer of a-L-fucopyranose linked 1Æ3 and sulfated at positions O-2 and O-4. The main fraction isolated from the acidic extract by ion-exchange chromatography was shown to be composed of a complex a-L-fucan with 28.9% of sulfate. Alginic acid (17.0% of dry algae) was the major polysaccharide obtained in the sequential extraction