Disruption of microalgal cells using high-frequency focused ultrasound

Bioresour Technol. 2014 Feb:153:315-21. doi: 10.1016/j.biortech.2013.11.054. Epub 2013 Nov 27.

Abstract

The objective of this study was to evaluate the effectiveness of high-frequency focused ultrasound (HFFU) in microalgal cell disruption. Two microalgal species including Scenedesmus dimorphus and Nannochloropsis oculata were treated by a 3.2-MHz, 40-W focused ultrasound and a 100-W, low-frequency (20kHz) non-focused ultrasound (LFNFU). The results demonstrated that HFFU was effective in the disruption of microalgal cells, indicated by significantly increased lipid fluorescence density, the decrease of cell sizes, and the increase of chlorophyll a fluorescence density after treatments. Compared with LFNFU, HFFU treatment was more energy efficient. The combination of high and low frequency treatments was found to be even more effective than single frequency treatment at the same processing time, indicating that frequency played a critical role in cell disruption. In both HFFU and LFNFU treatments, the effectiveness of cell disruption was found to be dependent on the cell treated.

Keywords: Cell disruption; Lipid extraction; Microalgae; Ultrasound.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Cell Fractionation / methods*
  • Chlorophyll / metabolism
  • Chlorophyll A
  • Colony Count, Microbial
  • Fluorescence
  • Lipids / chemistry
  • Microalgae / cytology*
  • Microalgae / growth & development
  • Microalgae / metabolism
  • Oxazines / metabolism
  • Staining and Labeling
  • Ultrasonics / instrumentation
  • Ultrasonics / methods*

Substances

  • Lipids
  • Oxazines
  • Chlorophyll
  • nile red
  • Chlorophyll A