Extraction Procedures and GCxGC-TOFMS Determination of Fatty Acids (FAs) in Cyanobacteria Cultures and the Effect of Growth Media Iron Concentration Variation on Cellular FAs Composition

Kessy F Kilulya Bhekie B Mamba

doi:10.4172/2161-0525.s7-009

Abstract

Cyanobacteria biomass obtained from freshwater bodies is known to contain a large amount of fatty acids. Thus, the current need to produce large amount of lipids for different application has identified cyanobacteria as one of the important sources of fatty acids. However, the production of fatty acids and the characteristics of its composition is a function of nutrients. This paper therefore, reports on the efficient extraction procedures of fatty acids from cyanobacteria biomass using ionic liquid solvent and organic solvent under ultrasonic solid liquid extraction technique and the effect of the variation of iron concentration in the growth media on the fatty acids composition of cyanobacteria biomass. The determination of fatty acids composition was performed using gas chromatography coupled to a time-of-flight mass spectrometer (GCxGC-TOFMS). The obtained fatty acids composition was found to be dominated by tetradecanoic acid (C14:0), hexadecanoic acid (C16:0), 7-hexadecenoic acid (C16:1), pentadecanoic acid (C15:0), 6,9,12,15-octadecatetraenoic acid (C18:4), γ-6,9,12-octadecatrienoic acid (γ-C18:3), 9,12,15-octadecatrienoic acid (C18:3), 9,12-octadecadienoic acid (C18:2), 9-octadecenoic acid (C18:1) and octadecanoic acid (C18:0). Statistically it was proved that the ionic liquid extraction protocol and that of ultrasonic solid liquid extraction by organic solvent were not significantly different. It was also revealed that the total amount of fatty acids in cultured cyanobacteria increased with decrease in iron concentration in the growth medium.

Highlights

Cyanobacteria are a diverse group of photosynthetic organisms found mostly in freshwater bodies [1]
In the comparisons of Ionic liquid (IL) extraction and volatile organic solvents (VOS) extraction procedures using the samples from Vaal Dam in South Africa, it was observed that ionic liquid extraction apart from being environmentally friendly it takes a very short time as compared to the organic solvent extraction procedure and suitable for handling a large number of samples
The determined fatty acids from cyanobacteria biomass were dominated by tetradecanoic acid (C14:0), hexadecanoic acid (C16:0), 7-hexadecenoic acid (C16:1), pentadecanoic acid (C15:0), 6,9,12,15octadecatetraenoic acid (C18:4), γ-6,9,12-octadecatrienoic acid, 9,12,15-octadecatrienoic acid (C18:3), 9,12-octadecadienoic

Summary

Introduction

Cyanobacteria are a diverse group of photosynthetic organisms found mostly in freshwater bodies [1]. Cyanobacteria, apart from producing different useful metabolites for different applications such as pharmaceuticals, production of fine chemicals, biofertilizers and animal feed [2,3,4,5], they are known to produce lipophilic extractives such as fatty acids which are somewhat toxic to aquatic organisms, especially unsaturated fatty acids. They are known to affect fish in freshwater bodies by interfering with the gill basolateral membrane ion-extrusion mechanisms leading to the death of fish [1,6]. This is attributed to the fact that at higher temperature the polar solvent decreases its polarity to allow it to capture compounds ranging from semi-polar to non-polar

Methods

Results

Conclusion