Evaluation of batch and semi-continuous culture of Porphyridium purpureum in a photobioreactor in high latitudes using Fourier Transform Infrared spectroscopy for monitoring biomass composition and metabolites production.

The culture strategy (batch or semi-continuous) was evaluated for biomass and metabolite formation in Porphyridium purpureum cultures in higher latitudes (>50° N). FTIR was used technology to characterise macromolecule biomass composition and the quality of the metabolites produced. Semi-continuous culture was found to be the most feasible strategy to develop microalgal biomass production facilities in higher latitudes, due to their average results in terms of growth rate (0.27 day(-1)), duplication time (2.5-4 days), maximum cell density achieved (1.43*10(7) cells m L(-1)), biomass productivity of 47.04 mg L(-1) day(-1) and an exopolysaccharides production of 2.1 g L(-1). FTIR technology applied to microalgal production is a valuable and reliable tool to determine on a daily basis not just the evolution of macromolecules composition (lipids, carbohydrates and proteins) but also for the characterisation of the metabolites produced such as phycoerythrin or exopolysaccharides in P. purpureum cultures.