Supercritical fluid extraction of fatty acids and carotenoids from the microalgae Spirulina maxima

The supercritical fluid extraction of fatty acids and carotenoids from the microalgae Spirulina maxima with carbon dioxide was studied. The effects of pressure and temperature on the yield and chemical composition of the extracts were assessed. The experiments were conducted at temperatures of 20-70 degreesC and pressures of 15-180 bar. The solvent mass flow rate was 3.33 x 10(-5) kg/s. Statistical analysis showed that neither the temperature nor the pressure significantly affected the total yield, but both the temperature and the pressure affected the extraction rate, and the effect of the temperature prevailed over that of the pressure. The extracts were rich in essential fatty acids and carotenes, and at 100 bar and 45 degreesC the extract contained no carotenes. Temperatures larger than 50 degreesC degraded the carotenes, as expected. The model of Goto et al. described the overall experimental extraction curves quite well.