Pharmaceutical potential of a fucoidan-like sulphated polysaccharide isolated from Halodule pinifolia.

In continuation with the screening of biological properties of seagrasses, we isolated sulphated polysaccharides from Halodule pinifolia. This is the first report that indicates the presence of fucoidan-like H. pinifolia crude sulphated polysaccharide (HPCSP) that are commonly found in brown algae being present in marine angiosperms. Fucoidan-like structures such as ß-mannuronic acid residues and sulphate groups were confirmed by Fourier transform infrared (FTIR) spectral analysis. There was a high content of uronic acid. The isolated HPCSP consisted mainly of total sugar (54.17%), protein (11.06%), carbon (18.25%), nitrogen (1.77%), hydrogen (3.62%), C/N ratio (2.04%) and uronic acid (2.61%). This isolated HPCSP was further investigated to determine anticoagulant and antioxidant activity. The HPCSP had high activity in the total antioxidant assay (125.86 mg ascorbic acid equivalents/g), DPPH radical scavenging rate (IC50 value 2.024 ± 0.12 µg/mL), deoxyribose radical scavenging rate (51.82% at 1000 µg/mL) and H2O2 radical scavenging rate (IC50 value 6.904 ± 0.34 µg/mL). In the anticoagulant assay, prolonged clotting time was observed with application of HPCSP with increasing concentrations. Further purification and characterization process is underway to confirm the structures of HPCSP. From the observed results, this fucoidan-like HPCSP could be developed as a new natural source of potential antioxidants in the functional food industry.

Hydrographic and sediment characteristics of seagrass meadows of the Gulf of Mannar Marine Biosphere Reserve, South India.

The aim of the study was to examine the spatial and temporal variations in the physicochemical parameters of seagrass meadows of the Gulf of Mannar, South India using multivariate statistical techniques, namely, cluster analysis (CA) and principal component analysis (PCA), to explore the relationship. There were clear spatial and temporal variations in physicochemical variables of the seagrass meadow of the Gulf of Mannar, but such changes were subjected to seasonal variations especially during monsoon and post-monsoon seasons. The multivariate statistical techniques, viz., CA and PCA helped in the discrimination of islands according to the physicochemical parameters of the seagrass meadows. It was inferred that electrical conductivity, nitrate, particulate organic carbon, and phosphate strongly determined the discrimination of 19 islands, respectively, upon physicochemical characteristics of their seagrass meadows. These results highlight the important role of seagrasses in the Gulf of Mannar Marine Biosphere Reserve.