A comparative study on effective cell disruption methods for lipid extraction from microalgae

Aims: To compare effective cell disruption methods for lipid extraction from fresh water microalgae. Methods and Results: Chlorella sp., Nostoc sp. and Tolypothrix sp. were isolated from fresh water ponds in and around Gandhigram, Dindigul District, Tamilnadu, India, and used for lipid extraction. Different methods, including autoclaving, bead beating, microwave, sonication and a 10% NaCl solution treatments, were tested to identify the most effective cell disruption method. The total lipids from three microalgal species were extracted using a mixture of chloroform and methanol. Fatty acid composition was detected by gas chromatography (GC). Nostoc sp. and Tolypothrix sp. showed higher oleic acid content of 13.27 mg g(-1) dw and 17.75 mg g(-1) dw, respectively, whereas Chlorella sp. had high linoleic acid content of 17.61 mg g(-1) dw when the cells were disrupted using the sonication method. Conclusions: Finally, the sonication method was found to be the most applicable and efficient method of lipid extraction from microalgae. The highest lipid content was extracted from Chlorella sp. Significance and Impact of the Study: In biodiesel production from microalgae, lipid extraction is a crucial step and important as cell disruption comes in this step. Therefore, the appropriate cell disruption method and device is a key to increase the lipid extraction efficiency.