Master Thesis: Anodic conversion of cyanobacterial biomass into a growth substrate for Mars in situ resource utilization

Establishing a long-term human presence on Mars will require the ability to produce materials from on-site resources. The alternative, sending materials from Earth, is unrealistic given the high launch costs and risks associated with long-distance resupplies. In general, there are no substantial sources of organic carbon or fixed nitrogen on Mars. This is an impediment to the application of bioprocesses as several industrially-relevant organisms are not capable of fixing carbon dioxide and/or nitrogen. As such, cyanobacteria have been proposed as primary producers to feed these bioprocesses since they can grow solely on Martian resources. Utilizing this cyanobacterial biomass as a feedstock requires a pre-processing step as the “raw” material is not easily metabolized. Microbial electrochemical systems (MES) may be the solution: an anodic compartment could serve as a platform to process cyanobacterial biomass into a suitable growth substrate for microorganisms and plants. The goal of this project is to develop the cyanobacterial-processing anode.

Research questions:

What microbial communities are best to colonize the anode and oxidize the cyanobacterial biomass?
How does the microbial community functionalize the cyanobacterial biomass? What are the products of interest to feed different types of bioprocesses on Mars?
For a selected microbial community: What are the best culture parameters? For example:
1. Biomass pre-treatment options;
2. Voltage applied;
3. Anode material;
4. Temperature;
5. Organic loading rate;

The general approach for this work will be the cultivation of pre-selected microorganisms in H-cells with a cyanobacterial biomass medium. This is followed by an analysis with qPCR, HPLC, fluorescence microscopy and electrochemical techniques.

Learning goals :

Planning and execution of a research project;
Cultivation techniques for a variety of different microorganisms (e.g. thermo- and mesophilic; aerobic and anaerobic);
Set-up and operation of microbial electrochemical systems;
Interpretation of the data from the analytics cited above;
Communication of scientific work both in oral and written forms.

In collaboration with:

Laboratory of Applied Space Microbiology from the Center Of Applied Space Technology And Microgravity (ZARM), University of Bremen

Beginning from:

September 2023

Language:

English

Period of time:

4 - 6 months

References:

Verseux, C. et al. Sustainable life support on Mars - The potential roles of cyanobacteria. Int. J. Astrobiol. 15, 65–92 (2016).

Ndayisenga, F., Yu, Z., Yu, Y., Lay, C. H. & Zhou, D. Bioelectricity generation using microalgal biomass as electron donor in a bio-anode microbial fuel cell. Bioresour. Technol. 270, 286–293 (2018).