Characterization of growth of marine cyanobacterium Phormidium fragile JN 112 under different regimes of pH, light intensity and media composition

Abstract

Optimization of culture collections for the mass cultivation of a fast growing filamentous marine cyanobacterium phormidium fragile JN112 was evaluated for pH, light intensity, nitrogen and phosphate concentration. Growth of the cyanobacterial isolate was measured at four different values each of pH (7.5, 8.0, 8.5 and 9.0) light intensity (30, 60, 90 and 120 μmol m-2s-1), nitrogen (0.075, 0.100, 0.125 and 0.150 g/L) and phosphate (0.02, 0.03 0.04 and 0.05 g/L). Growth determined in terms of protein and chlorophyll content for P. fragile JN112 indicated the preference of near neutral pH. Observation of cyanobacterial growth at higher pH values indicated the ability of P. fragile JN112 to tolerate high alkalinity. The maximum growth of P. fragile JN112 was determined at light intensity value of 30 μmol m-2s-1, nitrogen value of 0.1 g/L and phosphate value of 0.02 g/L.