Water soluble polysaccharides of marine algal species of Ulva (Ulvales, Chlorophyta) of Indian waters

Cold and hot water extracts of four different species of Ova viz. U. reticu lata, U. lactuca, U. rigida and U. fasciata were studied for their polysacc haride (PS) contents. In both the cold (CWE) and hot water (HWE) extracts r elatively higher yield of polysaccharides were obtained in Ova fasciata (6. 5 and 16% respectively). Ulva lactuca was found to contain higher amounts o f protein (33.1% in CWE), uronic acid (35.7% in HWE) and sulfate (23.8% in HWE). Cold water extracts were found to be enriched with hexose sugars, com prising a part of structural polysaccharide, whereas the hot water extracts were rich in rhamnose, xylose as well as glucose. The average molecular we ight of these polymers were found to be in the range 1.14 to >2.0 x 10(6) D a. Seasonal variation of PS of U. fasciata were also studied alongside. For this, cold and hot water soluble polysaccharides (PS) were isolated separa tely from the samples of Ulva fasciata Delile, collected monthly from a sin gle location during the season of algal growth (September-March) of the yea r 1995-96 from the west coast of India. Yield (17-21%) and viscosity (203 2 47 cps) of HWE were high during the active period of growth (October-Februa ry) of algae. Given the abundance of Ova species in Indian waters coupled w ith the potential utilities of their polysaccharides, the results obtained in this investigation would be useful in product development and bioprospec ting strategies.