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

Abstract

Porphyridium cruentum was grown in 10 L batch culture at 18°C, pH 8.0 and 28‰ 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)). α-Tocopherol and γ-tocopherol contents were 55.2 μg g −1 dry weight and 51.3 μg g −1 dry weight respectively.

Engineering Aspects Related to the Use of Microalgae for Biofuel Production and CO2 Capture from Flue Gases

“…Temperature is one of the main factors which regulate cellular, morphological, and physiological responses of microalgae (Mayo 1997;Durmaz et al 2007). High temperatures generally accelerate the metabolic rates of microalgae, whereas low ones lead to inhibition of microalgal growth (Munoz and Guieysse 2006).…”

Biological activity of microalgae can be enhanced by manipulating the cultivation temperature and irradiance

“…Similarly, the haptophycean Pavlova lutheri increases its relative EPA content from 20.3 to 30.3 M% and Isochrysis galbana has higher levels of α-linolenic acid and docosahexaenoic acid when the culture temperature is reduced to 15°C [114,115]. Cultivation of Porphyridium cruentum at low temperature (18°C) until reaching stationary growth stage results in accumulation of PUFAs (43.7% of total fatty acids), α-and γ-tocopherol (vitamin E) in cells [116]. An increase in PUFAs is expected as these fatty acids have good flow properties and are predominately used in the cell membrane to maintain fluidity during low temperatures.…”

Eicosapentaenoic Acid from Porphyridium Cruentum: Increasing Growth and Productivity of Microalgae for Pharmaceutical Products

“…where Nt and N0 are the cell density at time t and t0, respectively [23]. Moreover, the biomass productivity was presented by Equation ( …”

“…Production of arachidonic acid (ARA, C20:4 n-6) during EPA production is detrimental because high concentrations of ARA can reduce EPA production and make recovery difficult [19,22]. Therefore, it is critical to have minimum ARA and maximum EPA, which can be controlled by growth condition optimization [13,17,23]. Total fatty acid and EPA contents for unicellular algae have been reported to decline with increasing temperature [24].…”