Supercritical fluid extraction of astaxanthin from Haematococcus pluvialis and its antioxidant potential in sunflower oil

Supercritical fluid extraction technique was employed to extract astaxanthin from Haematococcus pluvialis. The antioxidant potential of the extract in sunflower oil was investigated in this work. The astaxanthin yield was 87.42% under the conditions of cosolvent 2.3 mL/g sample, pressure 43.5 MPa, temperature 65 degrees C. The extract was sensitive to oxygen and illumination, and it was suitable to be stored under the conditions of low temperature, low pressure of oxygen, and darkness to protect their antioxidant activity. L-ascorbic acid showed a significantly (P<0.05) synergistic effect on the antioxidant activity of the extract. Addition of the extract to sunflower oil made a significant (P<0.05) increase in oxidation stability at low temperature. The oil showed a significant (P<0.05) resistance to the initial oxidation at the frying temperature of 180 degrees C. However, the improvement of the extract amount to sunflower oil could not effectively prevent the oxidation of sample once the deep oxidation happened. Industrial relevance: Haematococcus pluvialis (H. pluvialis) is generally known as a rich source of astaxanthin (1.5-3.0%, w/w dry weight). In this work, supercritical fluid extraction technique was employed to extract astaxanthin from H. pluvialis, and the antioxidative stability under different storage conditions and antioxidant potential in sunflower oil of the extract were investigated. The results are useful for extensive utilization of H. pluvialis. (C) 2011 Elsevier Ltd. All rights reserved.