POLYSACCHARIDES PRODUCED BY TWO RED ALGAL STRAINS GROWN IN DIGESTATE WITH POTENTIAL ABILITY OF TUMOR CELL INHIBITION.

Research on the biological activities and applications of polysaccharides as active biocompounds synthesised by marine unicellular algae, which are, in many cases, released to the surrounding environment - exopolysaccharides, has revealed the possibility of many applications. We have investigated the growth and development of two red microalgae Porphyridium cruentum and Rhodella reticulata, where the used medium was decolourised with active carbon digestate from anaerobic digestion of agricultural waste - wheat straw. The biomass accumulation for both strains reached a dry weight of 5.2 to 5.5±0.2 mg ml-1, starting from 0.85 mg ml-1 m initial concentration for 6 days. Production of heteropolysaccharides was estimated to show increased yield of 0.35 mg ml-1 on the 6th day of cultivation for the Rhodella reticulata and 0.28 mg ml-1 for Porphyridium cruentum, compared to 0.25 mg ml-1 of the control - growth in a standard medium. The two isolated bioactive substances were then tested using 3-(4, 5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulphophenyl)-2Htetrazolium, inner salt - (MTS test), as potential antitumor agents on two cancer cell lines and a normal one to establish diminishing of cell vitality, mostly when applied to the high metastatic cell line MDA-MB 231-47%, when electroporation was applied by the heteropolysaccharide synthesised by the Porphyridium cruentum, grown in digestate. [ABSTRACT FROM AUTHOR]