A continuous preparation method of Spirulina platensis phenolic compounds and polysaccharides using supercritical carbon dioxide technology

摘要

Spirulina platensis was mixed with ethanol at a ratio of 1:10 (w v~(-1)) for 24 h to yield ethanol extract. An orthogonal design was performed at three different temperatures (40, 50 and 60°C), three different pressure levels (10, 20 and 30 MPa) and three different flow rate of Spirulina extract liquor (1, 2 and 3 ml min~(-1)). The carbon dioxide (SC-CO2) flow rate was maintained at 6 ml min~(-1). The highest selectivity of phenols and polysaccharides occurred at the operation temperature 60°C and pressure 30 MPa. Extract was also fractionated using SC-CO2 under the following operating conditions: 60°C and a pressure of 30, 15, 10 or 5 MPa into residual (R), F1, F2, or F3 fractions, respectively. The highest concentration of phenolic compounds was obtained in F3 fraction and the highest concentration of total polysaccharides was retained in R. F3 fraction contained the highest levels of total phenol contents and thus exhibited the greatest antioxidant ability.