Fatty Acids, Hydrocarbons and Terpenes of Nannochloropsis and Nannochloris Isolates with Potential for Biofuel Production

Abstract

Marine microalgae are a promising feedstock for biofuel production given their high growth rates and biomass production together with cost reductions due to the use of seawater for culture preparation. However, different microalgae species produce different families of compounds. Some compounds could be used directly as fuels, while others require thermochemical processing to obtain quality biofuels. This work focuses on the characterization of three marine microalgae strains native in Mexico and reported for the first time. Ultrastructure and phylogenetic analysis, suggested that they belong to Nannochloropsis sp. (NSRE-1 and NSRE-2) and Nannochloris sp. (NRRE-1). The composition of their lipid fractions included hydrocarbons, triacylglycerides (TAGs), free fatty acids (FFAs) and terpenes. Based on theoretical estimations from TAG and FFA composition, the potential biodiesels were found to comply with six of the seven estimated properties (ASTM D6751 and EN 14214). On the other hand, hydrocarbons and terpenes synthesized by the strains have outstanding potential as precursors for the production of other renewable fuels, mainly green diesel and bio-jet fuel, which are “drop-in” fuels with quality properties similar to fossil fuels. The validity of this theoretical analysis was demonstrated for the oxygenates of strain NSRE-2, which were experimentally hydrodeoxygenated, obtaining a high-quality renewable diesel as the reaction product.

The genome of Geosiphon pyriformis reveals ancestral traits linked to the emergence of the arbuscular mycorrhizal symbiosis

“…As a result of losses in fatty acid biosynthesis genes, AMF are entirely dependent on the host plant they associate with to obtain lipids [40][41][42][43]. Within this context, our findings suggest that, during the switch from regular AMS to a fungal-cyanobacteria symbiosis, G. pyriformis has evolved novel strategies to obtain lipids from its new host through the expansion of specific gene motifs.…”

“…Specifically, the G. pyriformis genome carries a striking over-representation of Lipase 3 protein domains that hydrolyze ester linkages of fatty acids. As Nostoc spp is known to produce a wide variety of extracellular lipids in high amounts [40][41][42][43], it is possible that these abundant lipids are released in the environment (like many other cellular compounds released by cyanobacteria [44][45][46][47]) and are then broken down by lipases to be used as an energy resource by…”

Influence of Photoperiods on Microalgae Biofilm: Photosynthetic Performance, Biomass Yield, and Cellular Composition

“…Cellular compositions of microalgae are critical evaluation parameters in various applications [26][27][28][29]. Generally, the main organic components of microalgae are lipid, protein, and carbohydrate, which represent approximately 90% of the microalgal dry biomass.…”

Towards high-quality biodiesel production from microalgae using original and anaerobically-digested livestock wastewater

“…J o u r n a l P r e -p r o o f 8 Livestock wastewater was demonstrated to provide sufficient nutrients for microalgal growth towards simultaneous treatment and biofuel production (López-Rosales et al, 2019) -N) in both effluents were below 0.5 mg/L.…”

“…nitrogen (N) and phosphorous (P), from wastewater. After short-term cultivation (usually within weeks), microalgae may synthesise lipids at levels up to 56% of the dry biomass, for potential biofuel production (López-Rosales et al, 2019). Moreover, the residual algal biomass could also be reused as valuable by-products, such as biochar (Maroušek et al, 2019) and fertiliser additives (Pan et al, 2018).…”