Page 93 - JCAU-5-3

Journal of Chinese
Architecture and Urbanism Regenerative algal futures

exchange rates of CO and O between the human and species
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are dependent on many factors; these factors can depend on
size and body type of the human and how much CO and
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O the human body produces in an enclosed environment.
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It would be important to measure CO exhalations from a
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species, because excessive production of CO2 by the species
could be detrimental to a human in an enclosed environment.
Any systems created would need to be rigorously managed.
Many experiments have been carried out with the C. vulgaris
strain (SAG 211-12) and research indicates that this strain
is a promising candidate and can benefit from long-term
cultivation (>180 days). Microalgae can be ideal companions
to support humans for long durations if the correct systems
and architectures are in place, as they possess the ability to
recycle human waste, remove CO and become a provider of
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O through photosynthetic activity. Even though green algae Figure 10. Diatom frustule of Coscinodiscus. Source: SEM image by Ram
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have the potential to provide life support, it can also lead to Shergill, Natural History Museum, 2022
certain digestive problems as side effects; however, forms and
relational species including cyanobacteria could be digested well as in space, and these species can photosynthesize in
without huge impact to humans (Escobar & Nabity, 2017). lower/higher light conditions. Recent experiments such
The chosen companion microalgae/cynobacteria species is as ATMOS (an experiment that studies a species in a
crucial to the success of a BLSS — for example, MELiSSA 96% N and 4% CO gas mixture with 100 hPa pressure)
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has proven that cyanobacteria and microalgae have benefits have shown that cyanobacteria Anabaena sp. is suitable
in bioregenerative systems. This is because certain species, for a cyanobacterium-based life support system (Verseux
like spirulina, are multi-functional. Various iterations in et al., 2021).
cyanobacteria biofilms have been created at University The resilient single-cell organism C. vulgaris is a
College London’s bio-integrated laboratory (Figure 9). eukaryotic green algae species that has an average diameter
Emergent photosynthetic living tissue in hydrogel scaffolds of 6µm (Vander Wiel et al., 2017). The species can adapt
could take up CO emissions and be a promising building to a range of climatic conditions and pH temperatures; it
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material. is resilient to contamination (Lakaniemi et al., 2012) and
It is important to assess which species could prosper is competent when facing shear stress. The species was
best in each location, as each species functioning within first discovered by the Dutch researcher Martinus Willem
a designed system will have benefits for each environment Beijerinck in 1890. Etymologically, the name comes from
it is placed in. On harsher parts of planetary surfaces, the Greek word “Chloros”, with the Latin term “ella”
temperatures can reach extremely low levels. In these elaborating on the organism’s microscopic size (Safi et al.,
harsher environments, diatoms could be possible candidates 2014). In the growth of the cell as it reaches maturity, a
to align with sympoietically. Diatoms have the ability to chitosan or chitin type layer compound of glucosamine
inhabit a great range of hostile environments on Earth. is formed (Weber et al., 2022). Once maturity is reached,
They can be found in polar regions, hot springs and geysers, environmental conditions can change this rigidity,
hypersaline and hyperalkaline lakes and pools. Certain depending on where the species is placed (Němcová &
species (Chaetoceras fragilis and Fragilaria sublinearis) Kalina, 2000). C. vulgaris reproduces asexually and at a
function in extreme low temperatures (Sterrenburg & fast continuous pace; in optimal conditions, it multiplies
Hoover, 2011). Diatom frustules can protect the organism manifold through autosporulation forming daughter
through a type of exoskeleton (Figure 10). Having this cells within its cytoplasm (Yamamoto et al., 2005). These
extra layer of protection can enable the species to be protoplasts divide into groups of 2, 4, and 8 until the mother
resilient and adaptable to harsh and extreme conditions. cell is broken, thus leaving the autosporangium. Once this
The frustule can provide the necessary protection against process occurs within 24 h, the daughter cells are set free.
adhesion, gliding, drying out and forming biofilms and Chlorella can be seen as a multifunctional species that can
colonies (De Tommasi et al., 2017). In terms of new be used on Earth for food production, vitamins, minerals,
alignments with species, various species of microalgae can biofuel, bioremediation, wastewater treatment, human
thrive in harsher climatic conditions — such as Galdieria health, bioethanol and more. The benefits of working with
sulphuraria and Prochlorococcus (Hume et al., 2015) — as Chlorella become manifold whether the organism is placed

Volume 5 Issue 3 (2023) 11 https://doi.org/10.36922/jcau.179