ARID ZONE JOURNAL OF ENGINEERING, TECHNOLOGY & ENVIRONMENT
AZOJETE - Centre for Satellite Technology Development Special Issue:

Space Science and Technology for Sustainable Development
AZOJETE, June, 2019. Vol. 15(SP.i2):57-74

Published by the Faculty of Engineering, University of Maidiguri, Maidiguri, Nigeria.

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ORIGINAL RESEARCH ARTICLE
SOCIO-ECONOMIC BENEFITS OF MICROGRAVITY RESEARCH

E. M. Afolayan1*, F. A. Oluwafemi1, E. O. Jeff-Agboola2, T. Oluwasegun2, J.O. Ayankale3

1Space Life Sciences Unit, National Space Research and Development Agency (NASRDA), Airport Road,
Abuja, Nigeria.

2Department of Biological Sciences, Joseph Ayo Babalola University, Ikeji Arakeji, Osun State, Nigeria.
3Ground Segment, Centre for Satellite Technology Development (CSTD), NASRDA, Abuja, Nigeria.

ARTICLE INFORMATION

Submitted: 15/10/2018
Revised: 24/11/2018
Accepted: 25/03/2019

Keywords:
Microgravity Research
Socio-Economic
Life-Sciences
.

ABSTRACT
Microgravity researches are conducted in low gravity environments.
These low gravity environments can be achieved in a number of
ways including parabolic aircraft flights, sounding rockets, drop
towers, clinostat. Gravity dominates everything on Earth, from the
way life has developed to the way materials interact. The reduction
of gravity causes significant changes in the chosen sample which
could be cells, plants, micro-organisms and small samples from
material sciences. The changes that occur as a result of the effect of
microgravity have led to discoveries that have been found to be of
socio-economic benefits. Socio-economic benefits involve benefits
in wealth, health, economic, environment. Sustainable development
in an economy includes economic growth, environmental protection
and social equality. Space technology applications such as in
microgravity stimulate economic growth and improve the quality of
life of people, in this way, it is beneficial to mankind. Overall,
products manufactured in microgravity environments have key
properties usually surpassing the best terrestrial counterparts.
Commercially, these products have attractive features that facilitate
marketing. This review considers the various benefits of
microgravity research in life-sciences such as in microbiology,
pharmacy, and medicine.

© 2019 Faculty of Engineering, University of Maiduguri, Nigeria. All rights reserved.

1.0 Introduction
Microgravity literally means very little gravity. Scientists do not use the term microgravity to
accurately represent millionth of 1g, as 1g is the Earth’s gravity. The microgravity environment,
expressed by the symbol µg, is defined as an environment where some of the effects of gravity
are reduced compared to what is experienced at Earth’s surface. Microgravity is generally
referred to as a state of weightlessness (Figure 1). Gravity at the Earth’s surface is referred to as a
one-gravity (1g) environment.

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Figure 1: In microgravity, astronaut Suni Williams could easily move this equipment that weighs
more than 700 pounds on Earth. Image Source – Credits: National Aeronautics and Space

Administration (NASA) (2012).

Sir Isaac Newton (1642-1727) described gravity as a force that governs motion throughout the
universe, not just on Earth. It is the attraction between all masses in the universe. The body is
accustomed to a one-gravity (1g) environment and feels different if that gravitational force is
changed (NASA, 1997). A gravity-related phenomenon is either directly affected by reduced
gravity or becomes significant as the gravity level is reduced (National Research Council, 2000).
In general, the focus of microgravity research and applications are in the study and assessment
of these biological, physical, and chemical phenomenology and related issues (Jeanne and John,
2015).

Conducting experiments in a microgravity environment has the potential for discoveries that can
both improve life on Earth and advance the understanding of space (Jeanne and John, 2015).
Actual microgravity environment can be provided for short duration by generating free fall
conditions close to the Earth’s surface with sounding rockets and airplanes in parabolic flight
and drop facilities (Clement and Slenzka, 2006). Orbiting spacecraft provide the best laboratories
for long periods of microgravity research. Scientists also use drop towers (Figure 2), aircraft, and
rockets to achieve short periods. An important advantage of having longer periods of time
available is that scientists have the ability to do research like it is done on Earth. Experiments can
be performed multiple times with different parameters (Oluwafemi et al., 2018a). Thus, scientific
researchers will be able to gather comprehensive data. The space laboratories such as the
International Space Station (ISS) (Figure 3), is such that platform (Oluwafemi et al., 2018a). The
space station provides a microgravity environment for researchers to conduct multidisciplinary
investigations, for educators to inspire next generation scientists and engineers, and to serve as
a stepping stone to future exploration that was not possible just some years ago. The space
station has the potential to improve and change lives on Earth with each investigation and
technology test that takes place in orbit. With collaboration from the original international
partnerships to the insights of inventors and integrators of the research and technology on the
ground, there can be anticipation of continued space station benefits for humanity (NASA, 2013).

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These all led to the development of several alternative ground-based instruments for simulation
of microgravity or elimination of gravity. Clinostat is one of such instruments. Types of clinostat
include the two-dimensional (2D) (Figure 4) and three-dimensional (3D) clinostat. To perform
experiments using 2D clinostat, possible samples are plants, cells, micro-organisms, fungi and
small samples from material sciences, but it cannot accommodate averagely more than 500g of
sample. Depending on the sample chosen, there are many factors such as the humidity,
temperature and light that need to be maintained at a specific range, while on the clinostat,
rotation speed, rotational axis angle and rotation direction depends on the discretion of the
experimenter (Oluwafemi et al., 2018a).

Figure 2: The Drop Tower in Bremen, Germany.
Image Source – Credit: European Space

Agency ESA (1998).

Figure 3: The International Space Station (ISS).
Image Source – Credit: NASA Television

(https://www.nasa.gov/mission_pages/station/
main/index.html)

Figure 4: 2D Clinostat.
Image Source – Credit: Microgravity Simulation Laboratory, Engineering and Space Systems

Department (ESS), National Space Research and Development Agency (NASRDA), Abuja, Nigeria.
Oluwafemi (2018a).

Since spaceflight microgravity experiments are unusual and expensive, this therefore restrict the
number of research scientists in this area. Therefore, the use of the microgravity simulations
equipment such as clinostat and drop tower has enhanced microgravity research on Earth; as
before the advent of the microgravity simulators, spaceflight microgravity experiments are
unusual and expensive, this therefore restricted the number of research scientists in this area
(Oluwafemi, 2018a). Several researches ranging from physical to life sciences have being
conducted under both real and simulated microgravity researches. For example, the principle
behind the use of the clinostat as a microgravity simulations equipment is that the centrifugal
and the centripetal forces are made equal (United Nations, 2013). Most of the plants grown on
the clinostats usually have better growth rates than those grown under normal Earth gravity

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(Oluwafemi et al., 2018b). This is usually determined by measurement of the root lengths of both
samples using ImageJ software to analyze the pictures of the plants’ seeds taken per time
(United Nations, 2013). The data generated can add to the analytical knowledge of the effect of
simulated microgravity on the plants experimented upon on Earth which will help for future
space experiments and missions on such plants. Since clinostat rotation majorly affects plants
growth positively (Oluwafemi et al., 2018b), this will help to increase the productivity in sectors
like agriculture for example by isolating the gene for growth from the microgravity simulations
sample and inserting them into the wild type of such plant (Oluwafemi et al., 2018b).

Therefore, the focus of this review work is on the benefits of microgravity research in the life
sciences. The benefits of microgravity research in the following fields are discussed: Biology,
Microbiology, Agriculture, Pharmacy and Medicine.

2. Why Research in Microgravity?
Gravity can be a disrupting factor for scientists, because it may distort the underlying physical
processes they attempt to study. It is fundamental for scientists to create microgravity conditions
in order to better observe and control phenomena and processes that are normally masked by
the effects of gravity, and to perform experiments that would be impossible on the Earth's
surface (Mark, 2017).

The reduction of gravity causes significant changes on the chosen samples during experiments.
These samples could be plants, cells, micro-organisms and nanoparticles. The changes that occur
as a result of the effect of microgravity have led to discoveries that have been found to be of
socio-economic benefits. Conducting experiments in a microgravity environment has the
potential for discoveries that can both improve life on Earth and advance the understanding of
space (Oluwafemi, 2017).

From integrated circuits, to silicon solar cells and memory foam, the benefits of previous
ventures into space have transformed the way we live and operate as humans. The promises of
this new generation of space exploration are equally vast, offering us the potential for an array
of possibilities from the design of more efficient therapies and better vaccines, to creating
stronger and more conductive materials, to developing new plant varieties that are better
adapted to extreme conditions. The opportunity for advances offers an infinite horizon of
possibilities that does not just lead to new products, but to entirely new categories that can
fundamentally change the way we live (Jeanne and John, 2015).

Some selected examples of research where microgravity as a tool is relevant for application-
oriented and industrial research, in a wide range from physical to life sciences under crystal
growth are (ESA, 1998): crystal growth of electronic and photonic materials from the melting or
the vapour phase allows to understand the influence of gravity on the crystal growth process
and produce benchmark samples which improve the quality and homogeneity of crystals of
compounds. This application is found in the high sensitivity X-ray detectors for medical
diagnostics (ESA, 1998). Another example is the crystal growth of biological macromolecules that
allows to monitor and control the process in order to grow high quality crystals suitable for

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detailed structure determination which identify the drug inhibiting an active molecule. This
application is found in the fast drug design on the basis of the detailed structure of the target
molecule (ESA, 1998).

The microgravity environment of space makes it an excellent biological laboratory (Kazuto, 2015).
In microgravity environment, scientists conduct experiments that are impossible to perform on
Earth, as this environment can serve as biological scaffold (NASA, 2008). Cells, microbes, plants,
samples from material science down to macromolecules behave differently in space. Monitoring
reactions and processes in the absence of the gravity variable - which can mask subtle
observations - can lead to a better understanding of infectious diseases and the human immune
response to them. The effect of microgravity on protein crystallization cannot also be over-
emphasized in the making of new drugs, since protein structure is key in therapeutics (ESA,
1998). This is because protein structure (primary, secondary, tertiary or quaternary) cannot
change under normal Earth gravity, but under microgravity, it can inter-convert to another. New
drugs can then be produced as a result of this change in structure of the protein. Structural
information gained from protein crystals can provide a better understanding of the role of a
given protein in the body’s immune system. (ESA, 1998).

Scientists have been studying the effects of microgravity on astronauts in orbit for some time.
An example is research on bone and muscle mass while in space (Kazuto, 2015). This has yielded
valuable data that can help the diagnosis and treatment of patients suffering from muscle
wasting diseases and bone density conditions such as osteoporosis. The ISS is where the best
scientists on - and off - Earth are performing these experiments.

Life in the microgravity environment of space brings many changes to the human body. The loss
of bone and muscle mass, change in cardiac performance, variation in behavior, and body-wide
alterations initiated by a changing nervous system are some of the most apparent and
potentially detrimental effects of microgravity. Changes to bone are particularly noticeable
because they affect an astronaut's ability to move and walk upon return to Earth's gravity. Some
of the processes and functions of bones change after the astronaut has lived in microgravity for
several days. In space, the amount of weight that bones must support is reduced to almost zero.
At the same time, many bones that aid in movement are no longer subjected to the same
stresses that they are subjected to on Earth. Over time, calcium normally stored in the bones is
broken down and released into the bloodstream. The high amount of calcium found in
astronaut's blood during spaceflight (much higher than on Earth) reflects the decrease in bone
density, or bone mass. This drop-in density, known as disuse osteoporosis, leaves bone weak
and less able to support the body's weight and movement upon return to Earth, putting the
astronaut at a higher risk of fracture. The exact mechanism that causes the loss of calcium in
microgravity is unknown (Shelley and Brian, 2009).

Many scientists believe that microgravity somehow causes bone to break down at a much faster
rate than it is built up. However, the exact trigger for this rate change has not been found.
Multiple lines of research, including hormone level, diet, and exercise, are being done in order to
determine exactly what causes, and may control or prevent osteoporosis during space flight. Just

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as astronauts eat a careful diet and get plenty of special exercise in space to prevent disuse
osteoporosis, steps can be taken to prevent osteoporosis on Earth (Shelley and Brian, 2009). A
balanced diet rich in calcium and vitamin D, exercise, a lifestyle free of smoking and alcohol,
bone density testing, and medication all prevent or alleviate osteoporosis (Shelley and Brian,
2009). Astronauts are not the only ones who must worry about bone loss. One and a half million
Canadians suffer from osteoporosis, a disease that causes bones to lose density and strength.
One in four women and one in eight men over the age of 50 have osteoporosis. Solving the
problem of bone loss in space will also help to prevent and cure the disease on Earth (Canadian
Space Agency, 2006). Therefore, actual and "simulated" spaceflights, with investigations
conducted at whole body and cellular levels, are needed to elucidate pathogeny of bone loss in
space, to develop effective countermeasures, and to study recovery processes of bone changes
after return to Earth (Zerath, 1998).

3. Socio Economy in Microgravity Research
Prosperity encompasses every good thing of life. It involves wealth, riches, sound-health,
affluence, well-being, plenty, ease, luxury, having-speed, fortune, peace, joy, success etc. Hence,
economic prosperity in this context means having a sustainable and developed economy.
Sustainable development in an economy includes economic growth, environmental protection
and social equality. Space technology applications such as in microgravity stimulates economic
growth and improves the quality of life of people; therefore, it increases economic prosperity
and reduces poverty. In this way, it is beneficial to mankind (Oluwafemi, 2018b).

Space technology has contributed immensely in the drastic transformation of space-faring
nations socially, industrially and economically. Most developed and some developing nations
like the USA, Russian, UK, Canada, China are well known to be space-pioneering nations. Space
technology through its spin offs and by-products has made an impact in every aspect of life,
from the economic and industrial development to the mini technologies used for terrestrial
applications. Space technology has helped in the improvement of information and
communications technology, infrastructure, agriculture, education, all these being the basic
factors for a sustainable development (Oluwafemi, 2018b).

Space technology application in economic growth is through these means: new jobs, new
markets, increased efficiency, improved competitiveness etc. It also includes through: activities
directly related to space products and services (satellites, launch vehicles, ground systems); new
capabilities, businesses, products and services derived from space technologies (i.e. spinoffs
from the space program); productivity enhancements and quality of life improvements, such as
from improved health, enriched baby food and other medical advancing spinoffs (Oluwafemi,
2018b).

Overall products manufactured in microgravity environments have key properties usually
surpassing the best terrestrial counterparts. Commercially, these products have attractive
features that facilitate marketing (NASA, 1997). These does not just lead to new products but to
entirely new categories that can fundamentally change the way we live.
As most of the plants grown under microgravity environment usually have better growth rates
than those grown under normal Earth gravity (Oluwafemi et al., 2018b). This can help to increase
the productivity in the agriculture sector by isolating the gene for growth from the microgravity

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sample and inserting them into the wild type of such plant (Oluwafemi et al., 2018b). This makes
this microgravity product better than the terrestrial counterpart.

NASA’s budget related to microgravity research and development exceed $350 million per year
between 2016 and 2017 (NASA, 2017). In 2013, with $314 billion in commercial revenue and
government spending, an average annual growth rate between 5% and nearly 8% was recorded
(NASA, 2017). This makes the space sector one of the fastest growing sectors in the world.

4. Patents Resulting from Microgravity Research
More than 818 patents have been granted from 1981 to 2012 as related to the subject of
microgravity as seen in Figure 5. The use of patents as an indicator of value creation signifies
economic potential (Jessica, 2012). Patents are government authority or license conferring a
right or title for a set period, especially the sole right to exclude others from making, using, or
selling an invention.

The use of patents as an indicator of value creation signifies economic potential. In addition to
granted patents in microgravity, additional 580 microgravity applications have filed with the U.S.
Patent and Trademark Office during the last decade. From microgravity technologies, there is a
prediction of a 21st century revolution in microbiotics that will dramatically change the approach
to human health care and food production" (Jessica, 2012).

Developments based on microgravity investigations and exploration creates compelling
competition between agencies, scientists and engineers. This includes both research and
technology developments, as seen in both cooperative and parallel projects that may lead to
benefits for humanity. "The fields of molecular and cellular biotechnology have already
demonstrated the competitive advantages of microgravity environments" (Jessica, 2012). The top
seven patent categories include the following: biotechnologies (36%), instrumentation/analytical
(13%), materials (12%), aerospace components (12%), and systems in the areas of thermal,
measurement, and human health (4% each) (Jessica, 2012).

Figure 5: This chart shows the upward trend of microgravity-related patents over 30 years, as
related to the International Space Station (ISS). Image Source - Credit: Jessica (2012).

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5. Benefits of Microgravity Research in Life Sciences
Life sciences comprise the fields of science that involve the scientific study of living organisms,
such as micro-organisms, plants, animals, and human beings, as well as related considerations
like bioethics. While biology remains the center-piece of the life sciences, technological
advances in molecular biology and biotechnology have led to a burgeoning of specializations
and new, often interdisciplinary fields. Life sciences are helpful in improving the quality and
standard of life. It has applications in health, agriculture, medicine, pharmaceutical industry, food
science industry (Valenti, 2014).

Influence of gravity on living organisms cannot be under-estimated. Gravity is a fundamental
force that has a marked influence on all life on Earth. Life scientists and biomedical researchers
exploit the space environment and in particular the near-weightlessness in order to answer
fundamental questions in basic biology relating to humans, plants and animals. Various
investigations on the response of microgravity on lungs, brain, nervous system, bones and
muscles have already been performed. Experiments in microgravity are needed to observe and
to determine the influence of gravity on the processing and amplification of signals involved in
the gravity sensing and response of cells, cell aggregates and tissue or whole organisms. Any
advance in the understanding of these fundamental aspects is important for the future of
medical science (ESA, 1998).

So many experiments in space life sciences has been carried out for example by the space life
science of National Aeronautics and Space Administration (NASA). Some of them are: NASA
researchers are learning new things about the human brain by studying how astronauts regain
their balance; flames form tiny almost-invisible balls that might reveal the secrets of combustion
here on Earth; taking small columns of sand into space, and returning with valuable lessons for
earthquake engineers, farmers and physicists (NASA, 2003).

5.1 Benefits of Microgravity Research in Microbiology
Micro-organisms are living microbes that cannot be seen without an aid of a microscope. They
could be unicellular, multicellular, or cellular for example viruses, bacterial cells, bacterial and
fungal spores, and lichens. Microbiology encompasses numerous sub-disciplines including
virology, mycology, parasitology, and bacteriology. Micro-organisms form biofilm which are
mainly antibiotics resistant, this makes them to play essential roles. Space microbiology is the
study of microorganism in outer space. Micro-organisms behave differently under microgravity.
Spaceflight microbes are great potential for novel therapeutics and vaccine.

The responses of microorganisms to selected factors of space (microgravity, galactic cosmic
radiation, solar ultraviolent radiation, and space vacuum) were determined in space and
laboratory simulation experiments. In general, microorganisms tend to thrive in the space flight
environment in terms of enhanced growth parameters and a demonstrated ability to proliferate
in the presence of normally inhibitory levels of antibiotics (Horneck et al., 2010). However, there
are some microbes that are beneficial to human health too. For instance, specimens of fungi
were found to produce new compounds that could be used for medical purposes. Due to the
stress of microgravity, fungi could produce new substances that might be used in cancer

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treatment. Note that, these microorganisms under normal Earth gravity will not produce such
compounds.

5.1.1 Secondary Metabolite Production
Basic research shows that space flight is generally conducive to bacterial growth, it has also been
hypothesized that secondary metabolite production of commercial interest might likewise be
enhanced. In the first of a series of experiments aimed at characterizing this response, (Lam et al.,
1998) showed that monorden production by the fungus Humicola fuscoatra was increased when
it was cultured on two different solid agar media in space. Interestingly, the increase was
attributed to microgravity environment as fungal biomasses were not significantly different
between the flight and ground cultures. A follow-up spaceflight experiment similarly showed
specific productivity of actinomycin D by Streptomyces plicatus in suspension to be increased as
well (Lam et al., 2002). In a related endeavor, Brown et al., 2002 found that E. coli not only
reached higher cell concentrations in space (and on clinostat) but also did so without consuming
more glucose, suggesting that a more efficient nutrient utilization process accompanied the
gains in growth with cost effectiveness. These promising studies culminated in an experiment
conducted using an automated fed-batch reactor placed onboard the ISS, which corroborated
the findings that actinomycin D production by Streptomyces plicatus increased during the first 2
weeks of the mission (Beniot et al., 2006).

Additional ground-based research aimed at evaluating secondary metabolite production has
been conducted using the RWV bioreactor microgravity simulation technique (Fang et al., 2000)
examined the effect of simulated microgravity on production of rapamycin by Streptomyces
hygroscopicus. Interestingly, a proportionally greater quantity of rapamycin was extracellularly
localized in the simulated microgravity environment, both with and without beads, than under
normal gravity conditions (Fang et al., 2000, Gao et al., 2001, Guadarrama et al., 2005).

5.1.2 Vaccine Development
A series of commercially sponsored vaccine development experiments has been performed
based on altered microbial virulence in spaceflight. These opportunities, now being carried out
aboard the ISS, are part of the National Lab Pathfinder (NLP) missions. The goal of the NLP
projects is to develop a vaccine against diarrhea-causing strains of Salmonella, for which no
vaccine is currently available. The study is conducted by launching Salmonella enterica and
Caenorhabditis elegans worms in isolated containment, after which they are serially mixed,
grown, and fixed in flight. These promising pilot studies suggest potential beneficial commercial
applications of enhanced antibiotic production efficiency and novel vaccine development from
microbial space research; however, conclusive results from this research are not yet available
(Tara, 2019).

5.1.3 Microbial Virulence and Drug Resistance in Space
Beyond the outcomes described above indicating that bacteria generally tend to fare well in
space in terms of reduced lag phase, increased population growth, and potentially enhanced
secondary metabolite production, other experiments further suggest that the effectiveness of

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antibiotics against microorganisms may be reduced and microbial virulence may be increased
(Nickerson et al., 2004).

Leys et al. (2004) reported that significantly greater concentrations of various antibiotics were
needed to inhibit in vitro bacterial growth in space. Two somewhat competing hypotheses can
be posed to address this observed outcome. Either bacterial resistance is increased in space or
overall drug efficacy and/or uptake rate is reduced.

Microbial virulence and drug resistance in space can also plausibly result in visible growth
occurring in space (or in a simulated space environment).

5.2 Space Farming and Benefits of Microgravity Research in Agriculture (Crop)
Space farming refers to the cultivation of crops for food and other materials in space or on off-
Earth celestial objects – equivalent to agriculture on Earth (Jessika, 2019). Figure 6 shows a
concept of a device for growing plant in space. Supply of food to space stations and proposed
interplanetary spaceships is staggeringly expensive. Furthermore, the impracticality of
resupplying interplanetary missions makes the prospect of growing food inflight appealing. The
existence of a space farm would aid the creation of a sustainable environment, as plants can be
used to recycle wastewater, generate oxygen (10m² of crops produces 25% of the daily
requirements of 1 person, or about 180-210grams of oxygen, continuously purify the air and
recycle faeces on the space station or spaceship. This essentially allows the space farm to turn
the spaceship into an artificial ecosystem with a hydrological cycle and nutrient recycling. It can
therefore be said that plants can assist the life support system since they can be used to purify
water and recycle carbon dioxide into oxygen. When grown on a large-enough scale, plants
therefore hugely impact how spacecraft and colonies are designed (Mike, 2017).

Figure 6: Showing Device for Growing Plants in Space.
Image Source – Credit: Jay (2015).

Back here on Earth, the impact of space farming will expand our knowledge of agriculture. There
are several spin-offs from ISS research and technology. Monitoring of crop growth for disease
and fertility differences are usually done on space farming and Earth crop farming. Farmers are
now using cameras aboard the ISS to come up with new and more efficient ways of maintaining
their crops.

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Researchers hope to transfer what they learn about growing food in the inhospitable climate of
space to equally challenging and hostile climates on Earth. They are collecting detailed
information about how plants grow and hope this information will help as land becomes scarcer
and less fertile. Goals include higher quality crops, higher crop yields and better controlled
agricultural systems and greenhouses (Mike, 2017).

Space farming has led to some other surprising and useful applications on Earth. One is a special
device called Bio-KES which converts ethylene into CO2 and water using ultraviolet light.
Ethylene causes plants to ripen and eventually spoil. A device like Bio-KES, used in food storage
units and display cases, could help increase the shelf life of produce, flowers and other
perishable items on Earth (Andrew, 2003).

Another area which could have unexpected consequences involves the study of plants' cell walls.
Through space farming, scientists may discover how to control and regulate how sturdy a plant
will grow. Some plants might benefit from this research in regards to better weather durability.
In addition, trees with less-sturdy cell walls would grow faster and be easier and cheaper to
process into paper. These genetically-modified trees could help slow deforestation by becoming
reliable, quick-growing resources for paper production (Mike, 2017).

However, nations engaged in space are actively assessing, both qualitatively and quantitatively,
the productivity, effectiveness, and Return On Investment (ROI) of these endeavors, given the
intense competition for resources and funding for alternate pursuits. With the high costs
associated with a space program and the limited resources available, a growing number of states
are recognizing the need to identify and provide value back to their societies in order to justify
spending on space. India, for example, has found a number of ways to articulate the benefit to
their people of improved space capabilities including affordable launch and expanding satellite
networks that yield terrestrial benefit through increasing crop yields by providing farmers with
greater environmental data, or by mitigating the loses from severe weather from better warning
systems (Jeff, 2016).

5.3 Benefits of Microgravity Research in Pharmacy
Space-based pharmaceutical research introduces an opportunity to improve the understanding
of how bioprocesses occur by removing the ever-present influence of gravity from a cell and its
surrounding environment. This unique research environment opens new horizons for exploring
unconventional bioprocessing techniques, perhaps initially for gaining knowledge to be applied
in terrestrial production facilities but also for future visions of space-based products with
sufficient value added to warrant commercially viable, on-orbit production (Kazuto, 2015).

Biological macromolecules such as proteins, enzymes and viruses play a key role in the complex
machinery of life. They possess active sites which make them bind or interact with other
molecules in a very specific manner that determines their biological function. They intervene in
the regulation, reproduction and maintenance mechanisms of living organisms, and they can be
the cause of diseases and disorders. Pharmaceutical drugs are molecules that inhibit the active
sites of macromolecules and, in principle, are intended to affect only the targeted
macromolecule. The vast majority of current drugs are the result of systematic testing, first at
molecular level, then at a clinical level (ESA, 1998).

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This extensive process significantly increases the cost of the product. With a detailed knowledge
of the 3D structure of a macromolecule, biochemists can restrict the range of drugs to be tested.
Furthermore, with a rational drug design approach, one may attempt to synthesize a drug
targeted exclusively on a specific macromolecule. That means a drug will perfectly bind to the
macromolecule and inhibit its biological function while remaining inert viz-a-viz other
macromolecules (ESA, 1998).

The 3D structure of the macromolecule can be discovered through the analysis of crystals by X-
ray diffraction: the diffraction pattern maps the structure of the molecules in the crystal. High
quality crystals lead to fast determination of accurate structure which leads to faster
identification of drug. Controlled crystallization requires a multi parameter approach. Gravity-
dependent parameters that may affect crystallizations include sedimentation, convection and
consequently nutrient transport rate and wall contacts (Kazuto, 2015).

Research efforts in laboratories aim to control the conditions in order to favor the nucleation of
a small number of crystals and, subsequently, steady growth to large sizes and crystallographic
perfection. Crystals of photosystem grown in space had a 10 to 20 times larger volume than
those grown on the ground and allowed the refinement of the structure from 4 Å to 3.4 Å. Space
crystals of collagenase diffracted with a higher intensity compared with their ground
counterparts, and allowed a further refinement of the structure. Under otherwise identical
conditions in space, fewer but larger thaumatin crystals were obtained with a measurably higher
internal order (ESA, 1998).

Comparable improvements in crystallization under microgravity have been reported in the
scientific literature for about 20% of the macromolecules tested. It is likely that the growth of
many crystals could be conducted more successfully in space. Current efforts toward
understanding and controlling the various mechanisms involved in the overall process should
continue, and a well-defined and documented experiment in microgravity will also help to learn
to control and optimize conditions, leading to better crystals. It will also permit the prediction of
which molecules of interest to the pharmaceutical industry will benefit from crystallization in
space conditions (Binot et al., 1998).

In Figure 7, the image is from a research on the ISS. It has been said that in microgravity, crystals
grow more slowly, but the molecules have time to more perfectly align on the surface of the
crystal which returns much better research data (Julie, 2015).

The other benefits of microgravity research and application in pharmacy are: it allows for longer
shelf life of drugs, gives better delivery routes of drugs and allows for better packaging of drugs.

Cells grown in microgravity replicate and grow into complex structures, unlike the way cells grow
on Earth (NASA, 2008). Pure, precisely ordered protein crystals of sufficient size and uniformity
for X-ray analysis are in demand by the pharmaceutical industry as tools for research. Structural
information gained from protein crystals can provide a better understanding of the role of a
given protein in the body’s immune system. Protein crystal research ultimately aid in the
development of more effective drugs and life-saving treatments for many diseases. Microgravity

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69

environment allows for the production of high-quality crystals. Protein crystals produced in
space are larger and more precisely ordered than those produced on Earth. These improvements
are important to scientists who analyze a crystal’s 3-dimensional structure-the key to
understanding a protein’s activity and possibly develop new and more effective drugs (NASA,
2008).

Figure 7: In microgravity, crystals grow more slowly, but the molecules have time to more
perfectly align on the surface of the crystal. Image Source – Credits: Brian Dunbar, National

Aeronautics and Space Administration (NASA), (2016).

5.5 Benefits of Microgravity Research in Medicine

Millions of people suffer organ or tissue loss from diseases and accidents every year. Yet
transplantation of tissues and organs is severely limited by the availability of donors. Growing
tissue samples outside the body is one of the major goals of current medical research, and the
microgravity environment has great potential for advancing this research. Experiments in
bioreactors are performed to study how cells multiply and interact to form skin, bone and
organs, and these cells and tissue culturing techniques also aids the study of cancer cells and
tumour formation (Kevin et al., 2018). Knowledge gained in microgravity on the regulation of cell
growth and differentiation will also help improve the cultivation of sensitive and highly
differentiated cell strains like those needed to obtain artificial organs. Studies of cells’ ability to
migrate in reduced gravity may produce new insights into the factors that allow cancer to spread.
When combined with biomedical research on Earth, these investigations could contribute to the
development of new ways to prevent and treat related diseases (ESA, 1998).

Simulating microgravity conditions on Earth could increase the preservation time of blood cells
both for therapeutic and research applications. To achieve this goal, one must first understand
how microgravity acts on the cell metabolism and then create these conditions in blood banks.
The use of stored blood cells is of importance in the treatment of bleeding or the pathological
deficiency of certain cell types. Platelets and red blood cells must be stored ready to use in
blood banks. Improving the preservation conditions would preserve the functional state of the
cells and therefore guarantee the efficiency of the treatment while at the same time reducing the
treatment costs (ESA, 1998).

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5.4 Benefit of Microgravity to Medical Instrumentation
Monitoring the health and body function of astronauts and related investigations have led to a
variety of new insights into the influence of space environment on human beings. Dedicated
instruments were developed for medical diagnostics and validated in space, and are now used
on Earth. An example is the fluid shift in the human body caused by the absence of hydrostatic
pressure observed under microgravity conditions. A dedicated instrument using ultrasound has
been developed to measure fluid accumulation in human tissues resulting from such fluid shift.
Analogous forms of edema occur preferentially in the facial tissue for kidney disease for example,
whereas cardiac patients show edema in the lower part of the body. In this way swellings in the
forehead or the tibia can serve as diagnostic or prognostic hints and be controlled by the new
ultrasound instrument (Christian, 2016).

For the measurement of inner eye pressure in space (Figure 8), a device which the user can
operate without help, has been developed that determines the increase due to microgravity. This
‘self-tonometer’ can also be used to control the increase of the intra-ocular pressure on Earth.
The instrument registers the pressure by total reflection of an infrared beam and is now in the
market for regular self-control and diagnostic of patients with risk of glaucoma, one of the most
frequent reasons for early blindness. The development of a non-invasive detection instrument to
observe eye movements in all three dimensions by video-oculography is another example. The
reaction of the eye to light stimulation can be registered continuously and has been used to
investigate the coordination of information on orientation obtained by the eye and by the
gravity-sensing organ in the inner ear. This method has been successfully tested on space
missions, and can be used in the detection of disturbances in the vestibular, neurological or
oculomotor domains. This diagnostic instrument is now commercially available for terrestrial use
(Christian, 2016; Binot et al., 1998).

Figure 8: Oculography being used to Measure the Pressure of the Eye on the ISS.
Image Source – Credit: Christian (2016).

6. Conclusion
Microgravity researches have the ability to widen our understanding of various challenges that
have been faced in life sciences which can in turn generate revenue for nations. Some emerging
and aspiring space-faring nations have developed assessment schemes to measure the value of
their investments in space and have generally identified positive returns by considering the
broader economic implications of space activities. It is generally easier to make the case for

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71

space program spending that generates and delivers sustainable value. From this review, haven
known the socio-economic benefits of microgravity research, it will be good to intensify effort
into it especially in life sciences because of its ability to give novel therapeutics.

The ISS, the drop tower and the 2D clinostat are some of the available platforms for microgravity
research. The 2D clinostat is a facility that is very much available for experimental purposes at
the Microgravity Simulation Laboratory, Engineering and Space Systems (ESS) Department,
National Space Research and Development Agency (NASRDA), Abuja, Nigeria. This equipment is
one of the scarce equipment for microgravity research around the globe and especially in Africa.

The concept for a controlled environment for planting in space where there is reduced gravity
could be made as spin-offs of space technologies which could lead to other surprising and
useful applications on Earth.

Research under microgravity using all the various means described are paramount to pursue and
to have a sustained economy, as the space sector is one of the fastest growing sectors in the
world. To impede or accelerate progress towards achieving this potential is funding, not just
funding but consistent funding, especially to develop robust university programs; as the
decisions made on the approach to funding the exploration, exploitation and development of
the resources required for microgravity research will determine the speed of progress. Aside
funding, awareness of the benefits of microgravity research, especially in life sciences should be
created.

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