Modelling of growth conditions for cyanobacterium Spirulina platensis in microcosms

The influence of cultivation conditions on the growth of the cyanobacterium Spirulina platensis was investigated by using two types of photobioreactors. In a rotative photobioreactor the doubling time (t(d)) was 3.54 days. The better value found for t(d) in an aerated photobioreactor by changing the initial nitrogen concentration (NaNO3) at 0.003, 0.015, 0.030 and 0.060 M was 2.5 days. A factorial experimental design was performed in order to estimate the contributions of initial nitrogen concentration, inoculum and cultivation time as well as their interactions. All three factors and their interactions proved to be significant in influencing the cellular concentration of S. platensis.