Mader M, Schwerna P, Buchholz R, van Geldern R, Barth J (2017)
Publication Language: English
Publication Type: Journal article, Original article
Subtype: other
Publication year: 2017
Book Volume: 26
Pages Range: 294-301
URI: http://www.sciencedirect.com/science/article/pii/S2211926417302011
DOI: 10.1016/j.algal.2017.07.026
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.
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://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: Download