Isolation and Fatty Acid Profile of Selected Microalgae Strains from the Red Sea for Biofuel Production

Abstract

Abstract:The isolation of lipid-rich autochthonous strains of microalgae is a crucial stage for the development of a microalgae-based biofuel production plant, as these microalgae already have the necessary adaptations to withstand competition, predation and the temperatures observed at each production site. This is particularly important in extreme climates such as in Saudi Arabia. Resorting to fluorescence activated cell sorting (FACS) we screened for and isolated several microalgal strains from samples collected from the Red Sea. Relying on the fluorescence of BODIPY 505/515 (4,4-difluoro-1,3,5,7-tetramethyl-4-bora-3a,4a-diazasindacene) and growth performance, four promising candidates were identified and the total lipid content and fatty acid profile was assessed for biofuels production. Selected isolates were classified as chlorophytes, belonging to three different genera: Picochlorum, Nannochloris and Desmochloris. The lipid contents were assessed microscopically by means of BODIPY 505/515-associated fluorescence to detect OPEN ACCESSEnergies 2013, 6 2774 intracellular lipid bodies, which revealed several lipid drops in all selected strains. This result was confirmed by lipid gravimetric determination, which demonstrated that all strains under study presented inner cell lipid contents ranging from 20% to 25% of the biomass dry weight. Furthermore, the fatty acid methyl esters profile of all strains seems ideal for biodiesel production due to a low degree of polyunsaturated fatty acid methyl esters and high amount of palmitic and oleic acids.

Screening and Evaluation of Some Green Algal Strains (Chlorophyceae) Isolated from Freshwater and Soda Lakes for Biofuel Production

“…The 18S rRNA gene is commonly used for the molecular identification of microeukaryotes [26,28]. Polymerase chain reaction (PCR) amplification of the genomic DNA of the algal isolates with the selected primers revealed efficient amplification.…”

“…The other sequences from isolates IL3, LC3, and LC11 were related to Micractinium strains having pairwise nucleotide sequence similarities ranging between 99.89% and 99.66%. Members of the division Chlorophyta are considered to be promising for biofuel production, due to their high growth rates and ease of cultivation, however different enrichment and gating procedures are required in order to isolate strains from other taxa [28,29]. …”

Sustainable Agriculture in the Arabian/Persian Gulf Region Utilizing Marginal Water Resources: Making the Best of a Bad Situation

“…For example, the very high light intensity and extreme temperature in the GCC region require strains which can flourish in such environments. Researchers have studied the biomass and lipid productivities of Nannochloris sp., Picochlorum sp., Desmochloris sp., isolated from Red sea, as feedstock for biofuel [93]. Similarly, in Kuwait, there were a few small-scale indoor studies of Nannochloropsis sp.…”

The fatter the better : selecting microalgae cells for outdoor lipid production

“…However, the present results with EtOH suggest that for some strains a polar solvent may be enough to guarantee cell penetration. Glycerol was also assessed as carrier for BP, considering previous positive results 51,67 . However in the present experiments a negative correlation between BP fluorescence and glycerol addition was observed (supplementary materials).…”

“…It is possible that the nonviable section detected at the start of the experiment was due to cellular damage caused by the sorting process 24 . Previous results have highlighted that FACS could be an effective tool to increase the lipid content in microalgae cultures 10,52,53,56,67 . Positive results with re-grow of sorted cell lines of microalgae have been reported 52,53,56 , but not yet with C. littorale.…”