Enhanced Light-Induced Biosynthesis of Fatty Acids Suitable for Biodiesel Production by the Yellow-Green Alga Eustigmatos magnus

Abstract

Optimization of the fatty acid profile in microalgae is one of the key strategies for obtaining valuable products and sustainable biofuels. Light intensity and light regimes exert an impact on the growth and metabolic process in microalgae. The objective of the present investigations was to assess the effect of light intensity and continuous light vs. photoperiod conditions on the growth and changes in the biomass composition in Eustigmatos magnus, with a focus on bioactive molecules such as lipids and fatty acids. The highest daily productivity of Eustigmatos magnus biomass and lipid yields were detected at continuous illumination and at the highest intensity of light. The results show that the content and composition of fatty acids was influenced by the culture conditions. The biomass of Eustigmatos magnus contained the highest concentrations of polyunsaturated fatty acids in the pphotoperiod conditions with the highest light intensity. This study shows that Eustigmatos magnus has a capacity for the accumulation of palmitoleic acid. A high intensity of continuous light improves the profile of fatty acids in Eustigmatos magnus, which can be suitable for biodiesel applications. At the high intensity of continuous light, Eustigmatos magnus lipids are characterized by high content of oleic acids and low content of saturated and monounsaturated acids.

Extracellular Polymeric Substances (EPS) as Microalgal Bioproducts: A Review of Factors Affecting EPS Synthesis and Application in Flocculation Processes

“…Light and the light regime are two crucial factors determining microalgal growth and metabolic pathways in autotrophic conditions [37]. The production of EPS by microalgal cells is a light-dependent process.…”

Auxin supplementation under nitrogen limitation enhanced oleic acid and MUFA content in Eustigmatos calaminaris biomass with potential for biodiesel production

“…Biomass accumulation was determined by measuring daily changes in optical density OD 650 (Cary 300/Biomelt spectrophotometer). The specific growth rate µ (d −1 ) was calculated as follows: where N 1 is the initial biomass concentration at time T 1 and N 2 is the biomass concentration at time T 2 11 .…”

“…where N 1 is the initial biomass concentration at time T 1 and N 2 is the biomass concentration at time T 2 11 . The doubling time of E. calaminaris biomass was calculated using Eq.…”

“…Extraction of crude lipids. Lipids were extracted from the centrifuged biomass after 17 days with a modified Bligh and Dyer method 11 . Briefly, the E.calaminaris biomass was subjected to a mixture of chloroform:methanol (1:2, v/v) with sonication.…”

“…marine Nannochloropsis spp., are regarded as model oleaginous species and are being investigated extensively. In contrast, only few studies have been focused on Eustigmatos strains occurring in soil; additionally, the biotechnological potential of these algae has not been explored yet 11 . So far, Eustigmatophyceae algae of the genus Nannochloropsis , Trachydiscusminutus, Vischeri and Eustigmatos magnus have only been analysed in terms of their ability to synthesise lipid compounds 4 , 11 – 13 .…”