Establishing a Framework of Nitrogen Acquisition for Martian Agriculture

Nitrogen (N) forms a crucial part of DNA, proteins, and other biomolecules and is an essential element to life. Luckily, N is abundant in Earth’s and Mars’ atmospheres in its atmospheric form (N2); however, plants and humans are unable to metabolize it in this state. N2 gas is only able to be consumed by undergoing nitrogen fixation, an intensive process that breaks the extremely-stable N ≡ N bond in order to form bioavailable ammonia (NH3). Many prokaryotes are capable of nitrogen fixation. Plants may uptake fixed N from these, which are then consumed by other lifeforms including humans as a source of nitrogen. Due to an apparent lack of biological activity on Mars, it is estimated that N will be overwhelmingly present as N2. If humans want to permanently settle Mars, which demands in situ food production, they must devise a means to efficiently fix nitrogen to enable agrarian success. Industrial nitrogen fixation is infrastructurally intensive, and this work therefore elects to evaluate biological nitrogen fixation as an avenue to Martian cultivation. Three different microorganisms are evaluated for their capacity to fix nitrogen: Rhodopseudomonas palustris (R. palustris), Azotobacter vinelandii (A. vinelandii), and Azospira suillum (A. suillum). Initial efforts to culture these in-lab are detailed. An outline for a modular system in which these organisms may be advantageously used is proposed to be evaluated with further research and studies.https://digitalcommons.usu.edu/fsrs2021/1018/thumbnail.jp

Enabling Mars Farms Through Microbial Remediation of Wastewater

This research evaluates the capacity of photoheterotrophic purple non-sulfur bacteria to utilize wastewater organics to grow and produce nitrogen-rich biomass. Inhibitory components of wastewater are determined. A scaled up production system is designed and utilized to culture bacteria in wastewater. The application of this technology in the production of agriculturally viable amounts of nitrogen-rich biomass is evaluated in the context of a Mars mission and enabling agriculture in a barren environment.https://digitalcommons.usu.edu/fsrs2020/1095/thumbnail.jp

Utilizing NASA-Funded Biotechnology to Improve Resource Management on Earth and in Space

USU senior Tyler is a Peak Summer Research Fellow studying biological engineering. Nitrogen, essential in soil fertilizer for crops, is produced traditionally in a way that uses natural gas and produces CO2. Tyler’s project has been to apply methods developed by NASA for astronauts to conserve and reuse resources to create nitrogen using wastewater and bacteria. Using this method would not only take advantage of waste we already have, but doesn’t produce CO2 and contribute to pollution. Tyler hopes to become a chemical engineer in the space industry and credits his undergraduate research experience. “There’s something about having to obtain knowledge that truly is brand-new that pushes the mind out of its comfort zone…I am an entirely new and better person.

Optimizing Nitrogen Fixation and Recycling for Food Production in Regenerative Life Support Systems

Nitrogen (N) recycling is essential for efficient food production in regenerative life support systems. Crew members with a high workload need 90–100 g of protein per person per day, which is about 14 g of N, or 1 mole of N, per person per day. Most of this N is excreted through urine with 85% as urea. Plants take up N predominantly as nitrate and ammonium, but direct uptake as urea is possible in small amounts. Efficient N recycling requires maintenance of pH of waste streams below about 7 to minimize the volatilization of N to ammonia. In aerobic reactors, continuous aerobic conditions are needed to minimize production and volatilization of nitrous oxide. N is not well recycled on Earth. The energy intensive Haber–Bosh process supplies most of the N for crop production in terrestrial agriculture. Bacterial fixation of dinitrogen to ammonium is also energy intensive. Recycling of N from plant and human waste streams is necessary to minimize the need for N fixation. Here we review approaches and potential for N fixation and recycling in regenerative life support systems. Initial estimates indicate that nearly all the N from human and plant waste streams can be recovered in forms usable for plants

Optimizing Nitrogen Fixation and Recycling for Food Production in Regenerative Life Support Systems

Nitrogen (N) recycling is essential for efficient food production in regenerative life support systems. Crew members with a high workload need 90–100 g of protein per person per day, which is about 14 g of N, or 1 mole of N, per person per day. Most of this N is excreted through urine with 85% as urea. Plants take up N predominantly as nitrate and ammonium, but direct uptake as urea is possible in small amounts. Efficient N recycling requires maintenance of pH of waste streams below about 7 to minimize the volatilization of N to ammonia. In aerobic reactors, continuous aerobic conditions are needed to minimize production and volatilization of nitrous oxide. N is not well recycled on Earth. The energy intensive Haber–Bosh process supplies most of the N for crop production in terrestrial agriculture. Bacterial fixation of dinitrogen to ammonium is also energy intensive. Recycling of N from plant and human waste streams is necessary to minimize the need for N fixation. Here we review approaches and potential for N fixation and recycling in regenerative life support systems. Initial estimates indicate that nearly all the N from human and plant waste streams can be recovered in forms usable for plants

Space Bioprocess Engineering on the Horizon

Space bioprocess engineering (SBE) is an emerging multi-disciplinary field to design, realize, and manage biologically-driven technologies specifically with the goal of supporting life on long term space missions. SBE considers synthetic biology and bioprocess engineering under the extreme constraints of the conditions of space. A coherent strategy for the long term development of this field is lacking. In this Perspective, we describe the need for an expanded mandate to explore biotechnological needs of the future missions. We then identify several key parameters—metrics, deployment, and training—which together form a pathway towards the successful development and implementation of SBE technologies of the future