Difference between revisions of "Team:Stanford-Brown-RISD/Experiments"

Our overall project can be broken down into four sub-projects. These are characterized as the following: Mycelium Material & Habitat Development, Mycelium Glue Project, Mycelium Filter Project, and finally the Mission Architecture that ties everything together. Below are the Experiments corresponding to each subproject.

Mycelium Glue

Mission Architecture

On another planet, mycelia will grow and expand to provide structural integrity for the house, inside which the astronauts will live. However, the mycelia requires a substrate (food) and oxygen to grow. Where will these supplies come from? Cyanobacteria.

Cyanobacteria are self-replicating, photosynthetic organisms that can convert the abundant carbon dioxide from the Martian atmosphere into oxygen. This oxygen can be used to grow the mycelia, as well as to keep astronauts healthy and alive inside the habitat. Moreover, it has been shown that mycelia can use cyanobacteria as a substrate (food) to grow (at normal Earth gas concentrations).

Our goal in this experiment is to demonstrate and quantify the oxygen production capabilities of a specific strain of cyanobacteria, known as Anabaena variablis. Achieving Earth-like percentages of oxygen (~20%) solely from the Anabaena, in combination with existing knowledge, would demonstrate the feasibility of cyano-based mycelial growth and Astronaut sustenance.

All experimentation was conducted inside an airtight, Nasco Whirl-Pak bag (total volume: 1627 mL). Two BD Gaspak Anaerobe Sachets were used to help establish an anoxic environment (down to .8% O2); Dry ice was used to establish a 90% + CO2 atmosphere, mimicking the Martian atmosphere. Wireless CO2 and O2 sensors measured the gas compositions over time, for the respective gases.

Using 425 ml of Anabaena liquid culture (@ end, OD600 is 1.449; OD750 is 1.035), oxygen production went from .8% to ~5% in 60 seconds. Then, oxygen gained 2.7% in 73,560 seconds (with an almost perfectly linear increase).

Given the empirically established rate, it will take ~92 hours (4 days) to achieve 20% oxygen, mimicking Earth's atmosphere. This time-frame is certainly reasonable in the context of our mission architecture.

Therefore, we have empirically quantified oxygen production for mycelial growth and astronaut sustenance, demonstrating promising results from cyanobacteria alone!