Microalgae are small organisms, which can be divided into 4 size categories as the
microplankton (20 to 1000 μm), the nanoplankton (2 to 100 μm), the ultraplankton (0.5 to 15
μm) and the picoplancton (0.2 to 2 μm) (Callieri & Stockner, 2002; Gopinathan, 2004). Their
small size allows them to do an effective photosynthesis, converting light energy with CO2
dissolved in water to produce lipids, carbon hydrates, proteins,