lnu.sePublications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Effects of changes in environmental conditions on neutral lipid content in natural microalgal communities from the Baltic Sea
Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. (MPEA)
2016 (English)Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
Abstract [en]

Microalgae have potential to mitigate eutrophication, CO2 emissions as well as the lack of resources for the growing world population. Neutral microalgal lipids are of interest as a raw material for renewable biofuels. Previous investigations using monospecific cultures of commercial strains have shown an accumulation of neutral lipids under environmental stress, such as changes in light, temperature and nutrient conditions. However, these responses are not explored in natural communities that are of interest for large-scale microalgal cultivation in Scandinavia.

The current study investigated light (high/low intensity), nitrogen condition (N:P 5:1 and 16:1), temperature (18°C and 12°C) and diurnal temperature shifts (18-6°C and 12-6°C)  effects on the lipid content of a natural community from the Baltic Sea (from the ALGOLAND photobioreactor at Cementa AB) in laboratory experiments. Further, an in situ latitudinal spring bloom gradient from the Baltic Proper to the Bothnian Bay was sampled to investigate natural processes of lipid accumulation. Neutral lipids were stained using a fluorescent marker (BODIPY) and analyzed with microscopy and flow cytometry.

In the laboratory experiments, diurnal temperature shifts caused the highest accumulation of neutral lipid content followed by nitrogen limitation that compensated for loss of lipids in low temperature. Light and temperature had less impact on the content of neutral lipids. Along the latitudinal spring bloom gradient microalgae biomass showed a concave pattern due to post-bloom conditions at low latitudes (station 1) and pre-bloom conditions at high latitudes (station 6). On the other hand, lipid content increased with increasing latitude. In station 2-6 high lipid content was associated with diatoms while in station 1 with dinoflagellates, indicating the potential of these microalgal groups for biofuel production.

This study highlights the effect of changes in environmental conditions on accumulation of neutral lipids in natural microalgal communities. The results could be applied to increase biomass lipid content in large-scale cultivation system during unfavourable conditions. Nitrogen limitation could compensate for the low temperature during the Scandinavian winter and spring, while diurnal shifts occur as a natural agent during autumn. 

Place, publisher, year, edition, pages
2016. , 36 p.
Keyword [en]
Microalgae, Neutral lipids, light, temperature, nitrogen, diurnal temperature shifts
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:lnu:diva-57620OAI: oai:DiVA.org:lnu-57620DiVA: diva2:1040113
Subject / course
Biology
Educational program
Akvatisk ekologi, masterprogram, 120 hp
Supervisors
Examiners
Available from: 2016-10-26 Created: 2016-10-26 Last updated: 2016-10-26Bibliographically approved

Open Access in DiVA

No full text

By organisation
Department of Biology and Environmental Science
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

Total: 62 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf