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


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