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7/27/2019 Spirulina Final Report FRANCE
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Lyce Paul Moreau Bras Panon Reunion Island
Spirulina, an asset for sustainabledevelopment
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Contents
Introduction..........................................................................................................................................3
I Spirulina, a photosynthetic bacterium................................................................................................3
a) Arthrospira platensis is a bacterium. ..................................................................3b) Spirulina carries out photosynthesis...................................................................4
c) Spirulina is edible and can be cultivated.............................................................4
II Spirulina in human nutrition.............................................................................................................4
a) The nutrients Spirulina brings.............................................................................4
b) Malnutrition........................................................................................................5
c) Spirulina brings elements that can help fighting against malnutrition................5
d) The use of Spirulina in the fight against malnutrition........................................5
e) The use of Spirulina in developed countries.......................................................6III The culture of Spirulina...................................................................................................................6
a) Mr Thbaudin's future Spirulina farm in Reunion island....................................6
b) Different kinds of farms......................................................................................7
c) An expanding market..........................................................................................7
IV Providing nutrients to an organic production of Spirulina..............................................................8
a) The purpose of our study.....................................................................................8
b) Setting up our culture..........................................................................................8c) Our final protocol................................................................................................9
d) Results.................................................................................................................9
e) Discussion.........................................................................................................10
f) Perspectives.......................................................................................................11
Conclusion..........................................................................................................................................11
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Introduction
We are Anas, Aurlie, Flora, Nelcie and Vairea. we are sixth form students in a high school called
lyce Paul Moreau. It's located in Bras Panon, East of Reunion Island.
One of our schoolmates has a disease that makes her often feel tired. A friend of her mother's
advised her to use Spirulina tablets againts this tiredness. She tried these tablets and felt relieved.
We were interested by an advertisement she showed us. This document stated that Spirulina was a
cyanobacterium. That's why we talked about that to our biology teacher, Mr Grondin.
Our teacher had met Mr Thbaudin. Mr Thbaudin would like to grow organic Spirulina in Reunion
Island.
We also learnt that Spirulina could be used as a cure against malnutrition.
Thanks to all this information, we decided to study Spirulina for the Focus Comenius project:
Spirulina can contribute to sustainable development, either in developed or in developing countries.
Sustainable development is a development that "meets the needs of the present without
compromising the ability of future generations to meet their own needs", as the BruntlandReport reads.
The goal of this document is to present some information we could gather about this topic.
It also presents an experimental study that we carried out: we tried to find a nitrogen source for
Spirulina that doesn't come from the chemical industry.
I deed M Thb di d e 't e i e it e e f hi S i li d e f
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Several cells align in small filaments called trichomes. These filaments may have different
shapes: coiled (it's the case for the Lonar strain that Mr Thbaudin gave us, and that we used in
our study) or curly (like the Paracas strain that Mr Thbaudin also grows).
External elements, like the beaks of flamingoes, may break the trichomes and participate in the
dissemination of Spirulina: Spirulina is unicellular.
Spirulina can be found naturally in lakes, for example in Tchad or in South America.
b) Spirulina carries out photosynthesis
Spirulina is blue-green. That's why, in the past, it was considered as a blue alga . In fact, it is a
cyanobacterium, that is a bacterium that carries out the same photosynthesis as plants. Spirulina
synthesises organic matter from mineral elements (water, mineral ions) and light energy. During thisprocess, it produces molecular oxygen O2 and consumes carbon dioxide CO2.
c) Spirulina is edible and can be cultivated
Even if it is not an alga, Spirulina is often refered to as a micro-alga. It has been consumed for very
long: Aztecs ate it 7000 years ago. It's also a traditional food, called Dihe, in some regions of Tchad.
The cell wall of Spirulina is chemically different from the cell wall of plant cells. Therefore,
humans can digest it far more easily.
II Spirulina in human nutrition
a) The nutrients Spirulina brings
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b) Malnutrition
Malnutrition is an inadequate diet which leads to the insufficient, excessive or imbalanced
consumption of nutrients . It also leads to medical conditions. Developing countries are the ones
which are the most affected. Malnutrition comes from poverty, inappropriate agriculture or nutritio-
nal ignorance. In poor countries, malnutrition may delay growth in children, increase mortality rate
and weaken immune systems.
c) Spirulina brings elements that can help fighting against malnutrition
Spirulina is protein-rich. It brings all the essential amino-acids that humans have to find in their
diets. A lack of these nutrients may lead to medical conditions. In some of them, the sufferer's blood
cannot retain its water. This water then flows into the sufferer's body. That's why some children
suffering from malnutrition have a swollen belly.
d) The use of Spirulina in the fight against malnutrition
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(a substance that has no pharmaceutical or nutritional effect) instead.
At the end of the experiment, 68% of the children of the first group had gained weight, whereas in
the other group, 43% gained weight, 37% did not change, and 20% lost weight.
Even if they do not remove all the uncertainties, these results are encouraging.
e) The use of Spirulina in developed countries
Molecules contained in Spirulina, and the testimonies of users result in a commercial success of
Spirulina in developed countries.
It's the case for athletes like long-distance runners, who use it because Spirulina has a reputation for
improving their performance.
One of our teachers practices capoeira at a high level. He told us that many of the athletes practicing
this sport use Spirulina as a diet supplement, for instance when their training leads to a strongincrease of their muscular mass. In such conditions, they need the nutrients brought by Spirulina.
Spirulina is also appreciated as a diet supplement that has no side-effect.
Large companies use this reputation to advertise around Spirulina.
The use of Spirulina in human diet has a potential for sustainable development in which a good
health of the population is important.
III The culture of Spirulina
a) Mr Thbaudin's future Spirulina farm in Reunion island
Mr Thbaudin has been setting up a Spirulina far for many years in St Leu, Reunion island. He has
installed pilot ponds in his courtyard.
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Mr Thbaudin uses a Secchi disk to monitor his production.
M.Thbaudin monitors his production with a Secchi disk. He measures the depth at which the white
disk canot be seen. The deeper it is, the more concentrated the culture.
When the culture is concentrated enough, Mr Thbaudin harvests the Spirulina.
He filters the culture using a piece of fabric. He dries the filtrate in the solar dryer. Before drying, he
gives the Spirulina paste a shape of spaghettis by means of a syringe.
Commercial production has not yet begun. Mr Thbaudin is choosing the final location of his farm.
Mr Thbaudin's growth medium is compatible with the standards of organic agriculture. 2 thirds of
his production will be sold, and the remaining third will be used for humanitarian purposes.
b) Different kinds of farms
There are differeny kinds of Spirulina farms. There are, for instance:
- Small farms which grow Spirulina in small ponds. They can be found in Africa, in Madagascar, or
i F Th ft h h it i l NGO' lik A t T h l i T h h l
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IV Providing nutrients to an organic production of Spirulina
a) The purpose of our study
Our purpose is to find a nitrogen source for the production of Spirulina. This source could be the
basis of an organic production of Spirulina.
The hypothesis that we tested was that aPhaseolus vulgaris beans extract could be a nitrogen
source. Indeed, this fabale is able to use the atmospheric nitrogen to synthesise its own proteins. It
does it thanks to bacteria that live in nodules located in its roots. We used beans that were cultivated
without chemical fertilisers and without pesticides.
We could have used legume weeds. Many people in Reunion use them when they raise animals in
their barnyards, especially rabbits. We didn't do it by fear of using toxic plants.
b) Setting up our culture
Before setting up our protocol, we made several tests. Here is a summary of what we did:
Number of
trial
Activities Results Conclusions
1 Cultures at our
homes
Some cultures died when they
were in direct sunlight
We stopped cultivating
Spirulina in direct sunlight.
We also learned how to use
tools like Secchi disks.
2 Measurements of
th i i
The increase in mass was larger
i th l ith
We saw that we had all the
t i l f t d
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c) Our final protocol
We tested 3 growth media, placed in transparent plastic glasses.
The Spirulina we used for all the plastic glasses came from the same culture.
In each plastic glass, there was 100 ml of a mixture of growth medium and Spirulina.
For each of the 3 growth media, there were 10 glasses.
Translucid Parafilm was put on the rims of the glasses.
The composition of each glass is summarized in the following bar chart:
20
40
60
80
100
120
Mixtures we used in our experiment
Distilled water
Beans extract
Growth medium wi-thout nitrogen
Growth medium
containing nitrogen
Spirulina
meofeachingredi e
ntoftheg
lasses(ml)
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e) Discussion
The following histogram shows the range of the yields of the harvested Spirulina in each growth
medium:
The -N medium was less productive (most of the corresponding yields are about 0.08 g in
weight) than the +B medium (most frequent yields around 0.12 g). The most productive medium
+N ( t f t i ld d 0 16 )
0,060,07
0,080,09
0,10,11
0,120,13
0,140,15
0,160,17
0
0,5
1
1,5
2
2,5
3
3,5
4
4,5
Ranges of the harvested mass of Spirulina
in each growth medium
With Beansextract
Medium with
nitrogen
Medium wi-
thout nitrogen
Bins (g)
N
uberofgla
ssesinea
chbin
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When comparing the 3 media, the probability that the difference was not significant was 0,000587.
This is far less than 5 times out of 100, which is a threshold that a lot of scientists use. Therefore,
we can say that the 3 averages are significantly different.
When comparing the media +B (with beans ) and -N (without nitrogen), the probability is
smaller than 0,0070, far less than 5 times out of 100 again. The beans extract has a significanteffect on the yield of the culture. It's a good way to replace the missing nitrogen of the -N
medium.
When comparing the media +B (with beans ) and +N (with nitrogen), the probability is
smaller than 0,1205. The beans extract causes an average yield that is not significantly different
from the yield caused by the complete medium. The beans extract is therefore a good complement
to the nitrogen-less medium.
These results validate our hypothesis.
However, we are not completely sure that the increase in yield comes from the nitrogen of the
beans. There are many substances in the beans, including growth factors that may have had an
effect. The experiments that could investigate that are above our possibilities.
f) Perspectives
The proteins of beans are complete: they bring all the essential amino acids that we need. Using
beans to grow Spirulina could lead to an increase of food prices. That's what happened with some
biofuels. Therefore, beans are not the best ingredients for the cultivation of Spirulina.
A it b f l i
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In such a context, our method could help the development of new growth media for
Spirulina.
Our work also shows the need for preserving biodiversity: Spirulina can improve the lives of many
people. Moreover, it shows that working with several living things (here, Spirulina and beans) can
sometimes be at the origin of new developments.
We'd like to thank Mr Thbaudin, Mr Jourdan, Antenna technologies, Mr Paus, who is working in
our science lab, and Mr Grondin, our biology teacher. We'd also like to thank the Comenius Agency
and the Cgnial committee which funded this study and our collaboration with students from
different European countries.
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Appendix : our results
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1 1,622 1,765 0,143 1 1,644 1,753 0,109
2 1,650 1,755 0,105 2 1,623 1,777 0,154
3 1,653 1,744 0,091 3 1,640 1,728 0,088
4 1,623 1,724 0,101 4 1,617 1,774 0,157
5 1,642 1,725 0,083 5 1,592 1,713 0,121
6 1,617 1,747 0,130 6 1,613 1,773 0,160
7 1,611 1,724 0,113 7 1,628 1,779 0,151
8 1,585 1,727 0,142 8 1,629 1,723 0,094
9 1,620 1,732 0,112 9 1,607 1,754 0,147
10 1,652 1,768 0,116 10 1,644 1,772 0,128
Average (g) 0,114 Average (g) 0,131
1 1,650 1,721 0,071
2 1,638 1,721 0,083
3 1,628 1,734 0,106
4 1,703 1,773 0,070
5 1,640 1,711 0,071
6 1,609 1,730 0,121
7 1,649 1,735 0,0868 1,641 1,718 0,077
9 1,645 1,711 0,066
10 1,626 1,739 0,113
Average (g) 0,086
Growthmedium withbeans extract(+B)
Completegrowthmedium (+N)
Repetitionnumber
Mass of thefilter at thebeginning(g)
Mass of filterandSpirulina (g)
Mass ofharvestedSpirulina (g)
Repetitionnumber
Mass of thefilter at thebeginning(g)
Mass of filterandSpirulina (g)
Mass ofharvestedSpirulina (g)
Nitrogen-lessgrowthmedium (-N)
Repetitionnumber
Mass of thefilter at thebeginning(g)
Mass of filterandSpirulina (g)
Mass ofharvestedSpirulina (g)