The effect of low temperature on fatty acid composition and tocopherols of the red microalga, Porphyridium cruentum

Porphyridium cruentum was grown in 10 L batch culture at 18 degrees C, pH 8.0 and 28%0 salinity. The cells were harvested in the stationary phase and the fatty acid composition analysed by GC and tocopherol content by HPLC. A total of 14 fatty acids were identified including saturated fatty acids (13:0, 14:0, 14:0 iso, 15:0, 16:0, 16:0iso) and monounsaturated fatty acids (MUFAs; 16:1(n-7), 18:1(n-7), 18:1(n-9). Polyunsaturated fatty acids (PUFAs) were the predominant fatty acids detected, reaching 43.7% of total fatty acids in the stationary phase of culture. Among the PUFAs, eicosapentaenoic acid (EPA, 20:5(n-3)) was dominant (25.4%), followed by 12.8% arachidonic acid (AA, 20:4(n-6)). alpha-Tocopherol and gamma-tocopherol contents were 55.2 mu g g(-1) dry weight and 51.3 mu g g(-1) dry weight respectively.