Journal article

The effect of high-intensity ultrasound on cell disruption and lipid extraction from high-solids viscous slurries of Nannochloropsis sp biomass

Shunyu Yao, Srinivas Mettu, Sam QK Law, Muthupandian Ashokkumar, Gregory JO Martin



The effect of ultrasonication on the cell rupture of marine microalgae Nannochloropsis sp. was studied as a function of the slurry solids concentration and treatment time. The concentrated viscous wet-biomass (~12 to 25% solids concentration) was subjected to ultrasonication (20 kHz) at 3.8 W/mL for up to 5 min. Compared to extraction without cell rupture, sonication led to a significant increase in lipid yield from ~11% to about 70% within 5 min of sonication. The extraction yield was found to decrease with increased solids concentration, with a large decrease between 20% to 25% solids. This is attributed to the increase in viscosity and decrease in speed of sound with increase in solids. T..

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Awarded by Australian Research Council (ARC)

Funding Acknowledgements

This work was performed in part at the Materials Characterization and Fabrication Platform (MCFP) and PFPC (Particulate Fluids Processing Centre) at the University of Melbourne. We thank the Australian Research Council (ARC) for providing funding through Discovery Projects Grant Scheme (DP170103791) and the University of Melbourne for providing infrastructure support. The authors would like to thank Dr. David R. A. Hill for his contribution in culturing and harvesting the microalgae. We thank Joshua Chung a Summer Research Exchange Program (SREP) student for his help with some of the experimental work.