Effects of photon flux density,CO2, aeration rate,and inoculum density on growth and extracellular polysaccharide production byPorphyridium cruentum

Growth and extracellular polysaccharide production byPorphyridium cruentum were measured as a function of several culture parameters. Photon flux density of 75 μmol m⁻² s⁻¹ and CO₂ concentration of 2.5% were found to be optimum for both growth and extracellular polysaccharide production. Interactive studies on these two parameters further confirmed that at these levels of photon flux density and CO₂, when applied together, both growth (5.9·10⁷ cells per mL) and extracellular polysaccharide production (1.9 g/L) were at the maximum. Maximum growth and extracellular polysaccharide production were observed at inoculum density of 10⁶ cells per mL and aeration rate of 500 mL air per min per liter.