Substitutions on the D-Galactose unit of agar polymers: Metabolic implications

Abstract

Regarding macroalgae's physiology, it is considered that substitutions on the L-Gal unit of agar polymers are representative of their biosynthesis. Studies performed within the Plant Cell Wall Polysaccharides Laboratory team have demonstrated the presence of 4-O-methyl-L-galactose in agar polymers from the rhodophycean thallophyte Gracilaria verrucosa and its linkage on the C-6 position of the D-Gal unit, which is also the site of O-methylation. Based on the 6-O-Me-Gal/ 4-O-Me-Gal ratio and the degree of substitution of D-Gal unit, a new approach for monitoring the characteristic events of agar metabolism was defined.