Treatment of Phaeodactylum tricornutum cells with papain facilitates lipid extraction.

Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EA, UK. Electronic address: .
Journal of Biotechnology (Impact Factor: 3.18). 07/2012; 162(1):40-9. DOI: 10.1016/j.jbiotec.2012.06.033
Source: PubMed

ABSTRACT Triacylglycerols (TAGs) from microalgae have the potential to be used for biodiesel, but several technical and economic hurdles have to be overcome. A major challenge is efficient extraction of intracellular TAGs from algae. Here we investigate the use of enzymes to deconstruct algal cell walls/membranes. We describe a rapid and simple assay that can assess the efficacy of different enzyme treatments on TAG-containing algae. By this means crude papain and bromelain were found to be effective in releasing TAGs from the diatom Phaeodactylum tricornutum, most likely because of their cysteine protease activity. Pre-treating algal biomass with crude papain enabled complete extraction of TAGs using heptane/isopropyl alcohol. Heptane as a single solvent was also effective, although complete recovery of TAG was not obtained. Economic implications of these findings are discussed, with the aim to reduce the complexity of, and energy needed in, TAG extraction.

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May 15, 2014