SEASONAL-VARIATION IN GROWTH AND CARRAGEENAN CONTENT OF CALLIBLEPHARIS-JUBATA (RHODOPHYCEAE, GIGARTINALES) FROM THE NORMANDY COAST, FRANCE

Study of the seasonal variation in the quality and content of iota car rageenan in Calliblepharis jubata from the Normandy coast of France sh ows that seasonal fluctuation of the environment affects the growth an d chemical composition of this red alga. Growth increases during winte r, when there is little synthesis of carrageenan and floridean starch is accumulated. When inorganic nitrogen content decreases, growth also decreases and stops (May to August); with high light intensity, the m etabolism is oriented towards a synthesis of parietal carrageenans to the detriment of the reserve products such as floridean starch.