Population and alginate yield and quality assessment of four Sargassum species in Negros Island, central Philippines

Four species of Sargassum in Negros Island, central Philippines, were monit ored for biomass, growth stages, alginate yield and quality. All four speci es exhibited different zonation, fertility patterns and seasonality in grow th and biomass. Mean biomass differed significantly for all species. Each species followed different patterns in alginate yield and viscosity in relation to growth stages. Highest yields were obtained from S. ilicifoliu m during its reproductive stage, S. feldmannii and S. polycystum during sec ondary growth while no significant difference in yield was found between di fferent stages of S. cristaefolium. Viscosity was highest in S. ilicifolium and S. polycystum during secondary growth. No significant difference in vi scosity was found between the different stages of S. feldmannii and S. cris taefolium.