Subcritical Ethanol Extraction of Lipid from Wet Microalgae Paste of Nannochloropsis sp.

In this paper, subcritical ethanol was applied to extract lipid from wet microalgae paste of Nannochloropsis sp. The effects of various operational parameters including moisture content, solvent (volume) to microalgae (dry weight) ratio, extraction temperature, and pressure, extraction time were investigated on the extraction performance of total lipids. The results showed that three factors, moisture content, solvent (volume) to microalgae (dry weight) ratio and extraction temperature, affected extraction efficiency obviously, but pressure and extraction time made little differences. The optimum extraction condition were 10% moisture, 40:1 ratio, 135 degrees C, 1.5 MPa and 50 min, which could produce 90.21% recovery rate of the total lipids. These results indicated that the subcritical ethanol extraction for lipid extraction from wet microalgae paste was efficient and economically successful due to ethanol's cheapness, safety, and easy recycling.