Chemical composition of polysaccharides of the red alga Tichocarpus crinitus (Tichocarpaseae) from different sites of Peter the Great Bay, Sea of Japan

A comparative analysis of the quantitative and qualitative composition of polysaccharides in the red seaweed Tichocarpus crinitus, collected at different sites of Peter the Great Bay in the Japanese Sea (Sivuch'ya Bay, Risovaya Bay and Sobol' Bay) was carried out. The sites differed in their biotopic and anthropogenic characteristics. The main monosaccharides of the investigated algal polysaccharides were galactose and 3.6-anhydrogalactose, which are structural components of carrageenan The highest contents of protein and glucose were found in the KCl-soluble fraction of algae from Sobol Bay that were experiencing increased anthropogenic pressure. Fourier transform infrared spectroscopy revealed that the KCl-insoluble polysaccharide fractions of all investigated algae had an identical structure corresponding to kappa/beta-carrageenan, while the KCl-soluble polysaccharide fractions had differences in their structures. The content of heavy metals and micro- and macroelements in polysaccharide fractions differed among algae growing in areas with different biotopic and anthropogenic conditions.