A NEW MOLECULE OF WATER-SOLUBLE POLYSACCHARIDE ISOLATED FROM EUCALYPTUS GROWING IN LEBANON

Salam Zein, Marianne Haddad, Elena Krivoruchko, Anatoly P. Sobolev, Sahar Azar and Hussein Kanaan*

ABSTRACT

Objectives: To study and compare the chemical structure characteristics of the polysaccharides extracted from leaves of Eucaluptus globulus with chemical structure of fucoidans extracted from Dictyopteris polypodioides brown algae. Materials and Methods: The water-soluble polysaccharides were extracted and the structures were identified by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, carbon-13 nuclear magnetic resonance and mass spectrometric analysis. Results: The total yield of fucoidans was 2.1% and 3.5% for Eucalyptus and Algae respectively. Results showed the presence of the typical structural of fucoidans: α-L-fucopyranose and fucoidan-like sulfated residues structures in both samples, whereas D-galactopyranosyl residues were absent in Eucalyptus. The main monosaccharides identified were fucose, glucose, galactose, xylose and glucuronic acid. Infrared characteristic band of sulfated groups were detected and sulfate substitutions of polysaccharides were indicated. Conclusion: Several similarities and small disparities in the structure of these polysaccharides were identified. The polysaccharide extracted from Eucalyptus leaves could be a promising new source of extra-marine fucoidans.

Keywords: Fucoidan, Eucalyptus, Brown Algae, Polysaccharide.