Fractionation microalgae

Cytological investigation was focused on the effects of the RO fraction on the green microalga Ankistrodesmus braunii (at the dilution 1 20) and seeds of Raphanus sativus (at dilutions 1 8, 1 10, and 1 14). 

An integrated process for highly purified PUFAs from microalgae has been developed at the University of Almeria (Molina Grima et al., 1996). The process basically employs solvent extraction, phase separation, urea adduction of fatty acids, and chromatographic separation of PUFA rich fraction the process is summarized in Figure 26.1. The same is applicable to recovery of PUFA rich lipid fractions from seaweeds as well. 

Here, is the fraction of the scattered light detected by the detector connected to the integrating sphere. Ideally, when all the scattered light is accounted for, is equal to unity. Moreover, at. 1 = 750 nm green microalgae are assumed to be nonabsorbing, i.e., /Cv5o = 0 m . Then, Eqs. (28) and (31) at 750 nm simplify to... 

Soulies A, Pruvost J, Legrand J, Castelain C, Burghelea TI Rheological properties of suspensions of the green microalga Chlorella vulgaris at various volume fractions, Rheol Acta... 

Whichever production mode (continuous or batch) is used, the control of light attenuation conditions, represented here by the illuminated fraction (with y < 1 for cyanobacteria and y = 1 =b 15% for microalgae), makes it possible to obtain the maximum biomass productivity of the cultivation system in light-limited conditions (volume and surface). If radiative transfer conditions are known (using a radiative transfer model, as already described), then the optimal biomass concentration can be determined theoretically, or else experimentally simply by varying the residence time and measuring corresponding biomass concentration and productivity (Takache et al, 2010). 

The amino acid composition of the protein fraction is very similar between different microalgae and relatively unaffected by light and nutrient conditions (Brown et al, 1997 Daume et al., 2003). On this basis, it is unlikely that protein quality is a major factor contributing to differences in the nutritional value of microalgae. 

The solar energy capture efficiency (Ca) is propoitiraial to the losses ( env) due to sub-optimal environmental conditions, the photosynthetic efficiency (Cph), the fraction of captured photons utilized by microalgae (jUp), and the fraction of energy consumed by respiration in microalgae (y). 

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