ABSTRACT

The triacylglycerol (TAG) was extracted from Microcystis sp., using a mixture of chloroform and methanol (2:1). The fatty acid methyl ester compositions for each method were identified using Gas Chromatography – Mass Spectroscopy (GC-MS). Techniques such as sonication, bead beating, sonication - hexane solvent, sonication – supercritical nitrogen, supercritical nitrogen – manual, bead beating - hexane solvent and bead beating - supercritical nitrogen were explored to determine the most rapid and efficient cell disruption. Sonication, bead beating and manual method showed 30.2 %, 41.88% and 11.21% overall average dissimilarity respectively. Hierarchical cluster analysis of the fatty acid composition obtained from different methods show four clusters for sonication and three clusters for bead beating. Sonication for a period of 60 minutes yielded higher quantity of fatty acids evident from higher quantity of palmitic acid (53.89%) with sonication of 30 minutes and higher stearic acid (56.27%) when the cells were disrupted through sonication for 60 minutes. This highlights that sonication of 60 minutes is effective for disruption of microalgae Microcystis cells and extraction of lipids.

KEY WORDS: Bead beating, lipid, Microcystis, palmitic acid, sonication, stearic acid, TAG