A new approach to quantify system efficiency with dissolved oxygen isotopes during engineered growth of Galdieria sulphuraria

Journal article
(Original article)


Publication Details

Author(s): Mader M, Schwerna P, Buchholz R, van Geldern R, Barth J
Journal: Algal Research
Publication year: 2017
Volume: 26
Pages range: 294-301
ISSN: 2211-9264
Language: English


Abstract

The microalgae Galdieria sulphuraria was grown in a first technical approach in a closed system experiment for 29 days. In this time period, 6 separate flasks were sampled for oxygen concentration and their stable isotope ratios (O-18/O-16) in dissolved and headspace phases. The oxygen isotope composition of the water was also analysed as an input for the transfer of its O-18/O-16 ratio to molecular oxygen via production by algae. This photosynthetic transfer of the isotope composition of water was counterbalanced by oxygen consumption that enriched both phases in O-18. For this reason, neither dissolved oxygen nor oxygen in the headspace reached the O-18-depleted oxygen isotope ratio of H2O despite excessive photosynthesis. Oxygen that was produced by photosynthesis accumulated with a yield of 13.96 mmol L-1 in the headspace and with 0.5 mmol L-1 in the fluid phase. This difference was due to rapid degassing of the solution. It was further amplified by preferential consumption of the dissolved O-2 phase. In order to quantify oxygen production and its consumption we determined photosynthesis/respiration (P/R) ratios with a formula that combined O-2 concentrations and its isotope ratios. It revealed a P/R ratio of 7.7 after 11 days. After this it decreased again and moved towards dominance of respiration. With this work our results introduce a new method to monitor the growth and efficiency of algae in controlled experiments.


FAU Authors / FAU Editors

Barth, Johannes Prof.
Lehrstuhl für Angewandte Geologie
Buchholz, Rainer Prof. Dr.
Lehrstuhl für Bioverfahrenstechnik
Mader, Michael
Lehrstuhl für Angewandte Geologie
Schwerna, Philipp Dr.-Ing.
Lehrstuhl für Bioverfahrenstechnik
van Geldern, Robert PD Dr.
Lehrstuhl für Angewandte Geologie


How to cite

APA:
Mader, M., Schwerna, P., Buchholz, R., van Geldern, R., & Barth, J. (2017). A new approach to quantify system efficiency with dissolved oxygen isotopes during engineered growth of Galdieria sulphuraria. Algal Research, 26, 294-301. https://dx.doi.org/10.1016/j.algal.2017.07.026

MLA:
Mader, Michael, et al. "A new approach to quantify system efficiency with dissolved oxygen isotopes during engineered growth of Galdieria sulphuraria." Algal Research 26 (2017): 294-301.

BibTeX: 

Last updated on 2018-07-08 at 02:42