Ceramiales algae 6 Rhodomelaceae 4 Seaweed 4 article 4 extraction 4 priority journal 4 seaweed 4 structure analysis 4 sulfate 4 unclassified drug 4 water 4 xylose 4 2 o methyl alpha galactose 2 3,6 anhydro alpha galactose 2 3,6 anhydro alpha galactose 2 sulfate 2 Acanthophora 2 Acanthophora spicifera 2 Agarans 2 Algae 2 Algal polysaccharides 2 Alkalies 2 Antiviral activity 2 Bacteria (microorganisms) 2 Calothrix confervicola 2 Cell Extracts 2 Ceramium rubrum 2 Chemical structure 2 Chromatographic analysis 2 Chromatography, Ion Exchange 2