umu.sePublikasjoner
Endre søk
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf
Subarctic microalgal strains treat wastewater and produce biomass at low temperature and short photoperiod
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
2018 (engelsk)Inngår i: Algal Research, ISSN 2211-9264, Vol. 35, s. 160-167Artikkel i tidsskrift (Fagfellevurdert) Published
Abstract [en]

In Northern countries, microalgal-based processes are challenging due to low light and temperature conditions during a significant part of the year. Three natural strains from Northern Sweden (Chlorella vulgaris, Scenedesmus sp., Desmodesmus sp.) and a collection strain (Scenedesmus obliquus UTEX 417) were cultured in municipal wastewater, comparing their performances, biomass composition and nutrients removal under continuous light at standard (25 °C) and low temperature (5 °C), short photoperiod (3 h light, 25 °C), or moderate winter conditions (6 h light, 15 °C). Only the natural strains grew at low temperature, highly consuming total nitrogen and phosphate (>80% and >70%, respectively) even during cold- and dark-stress. At reduced growth rates, C. vulgaris and Scenedesmus sp. produced similar amounts of biomass (>1 g/l) as in standard conditions. Scenedesmus sp. and Desmodesmus sp. showed phenotypic plasticity and increased carbohydrate content. Short photoperiod strongly reduced growth rates, biomass and storage compounds and induced flocculation in C. vulgaris.

sted, utgiver, år, opplag, sider
Elsevier, 2018. Vol. 35, s. 160-167
Emneord [en]
Subarctic climate, Microalgae, Wastewater treatment, Temperature, Photoperiod
HSV kategori
Identifikatorer
URN: urn:nbn:se:umu:diva-153114DOI: 10.1016/j.algal.2018.08.031ISI: 000447187700016Scopus ID: 2-s2.0-85052483715OAI: oai:DiVA.org:umu-153114DiVA, id: diva2:1262639
Prosjekter
Bio4EnergyTilgjengelig fra: 2018-11-12 Laget: 2018-11-12 Sist oppdatert: 2019-09-06bibliografisk kontrollert
Inngår i avhandling
1. Wastewater treatment and biomass generation by Nordic microalgae: growth in subarctic climate and microbial interactions
Åpne denne publikasjonen i ny fane eller vindu >>Wastewater treatment and biomass generation by Nordic microalgae: growth in subarctic climate and microbial interactions
2019 (engelsk)Doktoravhandling, med artikler (Annet vitenskapelig)
Abstract [en]

Nordic native microalgal strains were isolated, genetically classified and tested for their ability to grow in municipal wastewater. Eight of the isolated strains could efficiently remove nitrogen and phosphate in less than two weeks. Two of these strains, Coelastrella sp. and Chlorella vulgaris, were found to have high biomass concentration and total lipid content; also two Desmodesmus sp. strains showed desirable traits for biofuel-feedstock, due to their fast growth rates and high oil content.

The adaptation to subarctic climate was comparatively evaluated in three Nordic strains (C. vulgaris, Scenedesmus sp. and Desmodesmus sp.) and a collection strain (S. obliquus). Their growth performance, biomass composition and nutrients removal was investigated at standard (25°C) or low temperature (5°C), under continuous light at short photoperiod (3 h light, 25°C) or moderate winter conditions (6 h light, 15°C). Only the Nordic strains could grow and produce biomass at low temperature, and efficiently removed nitrogen and phosphate during both cold- and dark-stress. Phenotypic plasticity was observed in Scenedesmus and Desmodesmus under different growth conditions, adaptation to low temperature increased their carbohydrate content. Short photoperiod strongly reduced growth rates, biomass and storage compounds in all strains and induced flocculation in C. vulgaris, which, however, performed best under moderate winter conditions.

The symbiotic relationships between the Nordic microalga C. vulgaris and the naturally co-occurring bacterium Rhizobium sp. were investigated batchwise under photoautotrophic, heterotrophic and mixotrophic conditions, comparing the co-culture to the axenic cultures. The photoautotrophic algal growth in BG11 medium mainly supported Rhizobium activity in the co-culture, with no significant effects on C. vulgaris. In synthetic wastewater, a synergistic interaction only occurred under mixotrophic conditions, supported by CO2/O2 exchange and a lower pH in the culture, resulting in higher biomass and fatty acids content and more efficient wastewater treatment in the co-culture. Under heterotrophic conditions, the lower biomass production in the co-culture suggested a competition for nutrients, although nutrients removal remained efficient.

A pilot-scale high rate algal pond (HRAP) located in Northern Sweden was inoculated with the collection strain Scenedesmus dimorphus UTEX 417 and operated from spring to autumn. Using metabarcoding of 18S and 16S rRNA genes, the microbial diversity of eukaryotic and prokaryotic communities was revealed. S. dimorphus was initially stable in the culture, but other microalgal species later colonized the system, mainly due to parasitic infections and predation by zooplankton in summer. The main competitor algal species were Desmodesmus, Pseudocharaciopsis, Chlorella, Characium and Oocystis. Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were the most abundant bacterial phyla in the HRAP. The structure of the microbial communities followed a seasonal variation and partially correlated to environmental factors such as light, temperature and nutrients concentrations.

Overall, these results contribute with new knowledge on the establishment and optimization of microalgal-based wastewater treatment systems coupled with biomass generation in Nordic areas. The use of native microalgal species is proposed as a potential strategy to overcome the limitations posed to algal cultivation in subarctic regions.

sted, utgiver, år, opplag, sider
Umeå: Umeå University, 2019. s. 75
Emneord
Microalgae, Wastewater, Nitrogen, Phosphate, Biomass, Lipids, Subarctic Climate, Light, Temperature, Bacteria, Photoautotrophy, Heterotrophy, Mixotrophy, HRAP, Metabarcoding, Microbial Communities, Alpha-diversity, Environmental Factors
HSV kategori
Forskningsprogram
biokemi; mikrobiologi
Identifikatorer
urn:nbn:se:umu:diva-156470 (URN)978-91-7855-014-2 (ISBN)
Disputas
2019-03-15, Carl Kempe salen (KB.E3.03), KBC-huset, Umeå, 10:00 (engelsk)
Opponent
Veileder
Tilgjengelig fra: 2019-02-22 Laget: 2019-02-15 Sist oppdatert: 2019-02-21bibliografisk kontrollert

Open Access i DiVA

Fulltekst mangler i DiVA

Andre lenker

Forlagets fulltekstScopus

Personposter BETA

Ferro, LorenzaGorzsás, AndrásFunk, Christiane

Søk i DiVA

Av forfatter/redaktør
Ferro, LorenzaGorzsás, AndrásFunk, Christiane
Av organisasjonen
I samme tidsskrift
Algal Research

Søk utenfor DiVA

GoogleGoogle Scholar

doi
urn-nbn

Altmetric

doi
urn-nbn
Totalt: 148 treff
RefereraExporteraLink to record
Permanent link

Direct link
Referera
Referensformat
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Annet format
Fler format
Språk
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Annet språk
Fler språk
Utmatningsformat
  • html
  • text
  • asciidoc
  • rtf