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Although most algal biofuel research has focused on microalgae, macroalgae are also potential sources of lipid for the production of biodiesel and other liquid fuels. Reliable, accurate methods for assessing the lipid composition of biomass are essential for the development of macroalgae in this area. The conventional methods most commonly used to evaluate lipid composition, such as those of Bligh and Dyer and Folch, do not provide complete extraction of lipids in photosynthetic cells/tissues and therefore do not provide an accurate accounting of lipid production. Here we present a 2-EE lipid extraction protocol, a method which has been demonstrated to be superior to conventional lipid extraction methods for microalgae, adapted for use with macroalgae.
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Bacterial diketopiperazines stimulate diatom growth and lipid accumulation
Abstract Diatoms are photosynthetic microalgae that fix a significant fraction of the world’s carbon. Because of their photosynthetic efficiency and high-lipid content, diatoms are priority candidates for biofuel production. Here, we report that sporulating Bacillus thuringiensis and other members of the Bacillus cereus group, when in co-culture with the marine diatom Phaeodactylum tricornutum, significantly increase diatom cell count. Bioassay-guided purification of the mother cell lysate of B. thuringiensis led to the identification of two diketopiperazines (DKPs) that stimulate both P. tricornutum growth and increase its lipid content. These findings may be exploited to enhance P. tricornutum growth and microalgae-based biofuel production. As increasing numbers of DKPs are isolated from marine microbes, the work gives potential clues to bacterial-produced growth factors for marine microalgae.
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- Award ID(s):
- 1632976
- PAR ID:
- 10286470
- Date Published:
- Journal Name:
- Plant Physiology
- Volume:
- 186
- Issue:
- 2
- ISSN:
- 0032-0889
- Page Range / eLocation ID:
- 1159 to 1170
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1093/plphys/kiab080
