Background of the Study
University of Illinois Extension (2017) mentioned that insects make up more than half of
all living things in the world. In fact, today, there are more than a million know species of
insects- that’s 1,000,000- and there are many more waiting to be discovered. Insect repellents
can help reduce your risk of being bitten by insects and therefore reduce your risk of getting a
disease
carried
by mosquitoes or ticks.
Numerous
products
are
available
to
repel mosquitoes and ticks (National Pesticide Information Center, 2016). Technically, as
mentioned by Gumban (2013), an insect repellant is any chemical or natural that causes insects
or other arthropods to make directed, oriented movements away from the source of repellent.
And lemon grass can be used as a natural insect repellent (Helmenstine, 2011).
As cited by Gumban (2013) & Catapang, Garcia& Villongco (2015), lemon grass is a very
popular and used for medicinal, food and insect repellent products. The lemon grass oils are
used in cosmetics, soaps, perfumes, dyes and odorizes along with thousands of other products.
Lemon grass has thin stems, and the flowers are white, cream or green. It grows around 8 feet
in height in some cases but in majority it grows around 4 feet. Cymbopogon citratus also known
as lemon grass or in our local term tanglad is mainly found in tropical Asia in countries such as
India, Myanmar, Malaysia and Philippines. It can be planted anywhere, and it is easy to grow
and doesn’t need much cultivation unlike other plants. Because of its characteristics, people
can be encouraged to plant their own, at their backyards and this can inspire them to be
environmentally friendly, for the benefit of both Mother Nature and themselves. It is to be sold
at an affordable and reasonable price, which can be bought by the populace.
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Many products pertaining chemical compound used as active chemical ingredient in an
insect repellent are now turn to all natural ingredients as more and more negative data is
released. Lemon grass is extremely safe and is listed on the EPA’s GRAS (generally regarded as
safe). That is why people all over the world have come to rely on the potent insect repellent
properties of lemon grass and utilize it as a personal and area spray (Gumban, 2013).
Statement of the Problem
This study aims to create an affordable and natural yet effective insect repellent.
Thus, it aims to answer the question:
1. How effective the lemon grass as a mosquito repellent?
Hypothesis
H0: The lemon grass cannot be an effective mosquito repellent.
H1: The lemon grass can be an alternative mosquito repellent.
Significance of the Study
This study is beneficial to the people in the community especially those who are
engaging in any outdoors activities. The children will benefit the most because they are
engaged in some outdoor activities, and the knowledge of the parents that the lemon grass can
be an insect repellent would help them prevent different diseases that might be acquired.
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Scope and Limitation
The researcher defines the scope and limitation in order to give clear understanding on
the parameters of the study in terms of the following:
Focus. This study focuses on the effectivity of the lemon grass as a mosquito repellent.
Respondents. The respondents of this study will be the residents in Brgy. Buenavista, Surigao
City.
Place. This study will be conducted in the Brgy. Buenavista, Surigao City.
Review Related Literature
Whether morning or afternoon, inside or outside the house, in nature, mosquitoes
always ruin someone’s relaxation. These insects bites can be so painful and irritating especially
to those who experience allergic reactions. In connection with that, Aardvark Ant & Pest
Control Incorporation (2015) mentioned some ways on how to prevent mosquito bites. First
way is to wear repellent, it may seem very obvious but this repellent will definitely help people
in preventing mosquito bites, also it is better if it is sprayed more in the clothes to be able to
put not much in the skin. Next, is to put candles, since mosquitos don’t want smoke, this way
can be effective somehow. Lastly, removing stagnant water, which can be the made as
mosquitoes home. In addition with that, frequently change the water that needs to be kept
inside the house.
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Mercola (2017) mentioned that Lemongrass oil is also known for its ability to repel
insects, such as mosquitoes and ants, due to its high citral and geraniol content. Spray it around
your home, diffuse it or rub a diluted mixture on your skin.
Lemongrass oil's refreshing scent makes it valuable aroma therapeutic oil. Its clean and
calming aroma helps relieve stress, anxiety, irritability and insomnia, and prevent drowsiness.
Lemongrass oil can also help relax and tone your muscles, as well as relieve muscle pain,
rheumatism, period cramps, stomachache, toothache, migraines and headaches.
Also, Lemongrass oil's main compounds includes are geranyl acetate, geraniol, myrcene,
nerol, myrcene, citronellal, terpineol, methyl heptenone, terpineol, dipentene, geraniol, neral,
farnesol, limonene, and citral and farnesol. These are known to have antifungal, antiseptic,
insecticidal and counterirritant properties. Citral is known for its antimicrobial effects, and can
help kill or suppress the growth of bacteria and fungi. It's said that lemongrass oil's quality is
generally determined by its citral content. Limonene, another one of lemongrass' beneficial
compounds, is known for helping reduce inflammation and kill bacteria (Mercola, 2017).
Methodology
Material/Equipment
1. Lemon grass (30 pieces)
2. Stainless pot with cover
3. Strainer
4. Stainless or steel bowl
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Study Area
This study will be conducted in Barangay Buenavista, Surigao City.
General Procedure
A. Collecting of Lemon Grass
30 pieces of lemon grass (Cymbopogon citratus) leaves will be collected near the
Elementary School in Brgy. Buenavista, Surigao City. The leaves will be washed in a clean water
and let it dry before extraction process takes place. The leaves need to be clean in order for the
unnecessary organism be washed away.
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B. Extraction Process
1. The extraction process will be done through distillation process. Since the location
doesn’t have the apparatus needed, the researcher will be using an improvised
apparatus which are available in the area. The consumables are water, ice and the
lemon grass. The stainless pot will be heated and will be filled with purified water to
the level just below the strainer bottom when it is placed.
2. A strainer will be put or inserted on the top of the stainless pot and will be filled with
lemon grass leaves.
3. The stainless or steel bowl will be put in the center of the strainer to be the
receiving vessel where the extract can be found.
4. Position the cover pot on top of the strainer, make sure that the drip tip is centered
over the receiving vessel (stainless/steel). The pot will be filled with ice as much as it
can hold.
Note: it is not necessary to add water to the pot cover. Just utilize the ice on top of
it.
5. Boil the setup to 15-30 minutes with the temperature that cannot damage the
lemon grass leaves.
6. Get the extract of the lemon grass on the receiving vessel.
C. Testing the Extract
The extract will be put in the spray container and test it to the resident of Brgy.
Buenavista, Surigao City. The time will be recorded as to when will the effectivity of the
repellent ends.
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Results and Discussions
A. Findings
As the result, the respondents’ experiences zero mosquitos’ bites until 2 hours of
waiting, while the control setup has mosquito bites landing in just a matter of 5 minutes right
after the testing time. Table 1 shows the whole observation of the experiment and the interval
time of the mosquito to land in the person’s skin.
Table 1. Time of effectivity of the lemon grass extract to the respondents
Respondents
Amount of Lemon
Time of effectivity
grass extract (mL)
(minutes) after testing the extract
Person 1
3 mL
120
Person 2
2 mL
95
Person 3
1 mL
45
Person 4
(control)
0 mL
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B. Discussions
According to SFGATE (2017), Lemon grass (Cymbopogon) is a genus of about 55
related grass species or varieties. The lemon grass plant or the oil extracted from
it are used in cooking, aromatherapy, medicinal preparations, teas and cosmetics.
Lemon grass also has insecticidal properties and the extracted oil is used in insect
repellents and insecticidal sprays. The same chemical compounds are found in all
lemon grass varieties, but the amounts may differ. Citronella oil, a common
mosquito repellent, is extracted from citronella grass (Cymbopogon nardus).
Citronella candles are widely used to repel mosquitoes. Citronella oil and
other lemon grass oil extracts are used in sprays and topical applications. Studies
with birds and starved mosquitoes, using topical applications of lemon grass oil
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in the form of cream or liquid paraffin solution, was effective protection against
the hungry mosquitoes, comparable to commercial mosquito repellents,
according to a 2002 report in the journal Phytomedicine SFGATE, 2017). That is
why the results found out when the extract of the lemon grass was tested, it was
effective and can be an alternative mosquito repellent.
This study of lemon grass (Cymbopogon citratus) confirmed that the oil has
an insecticidal property and can be assume as safe due to its natural product
based.
Conclusion
The researcher concluded that the lemon grass can be an alternative mosquito repellant
in the people living in Brgy. Buenavista because of its insecticidal property that makes the
mosquitos repel in the skin of the respondents. It can also contribute to the prevention of
malaria and dengue.
Also, the result says that the alternative hypothesis was right.
Recommendations
Based on the conducted experiment, the researcher recommends the
following for further improvements:
1. Use other alternative plant that can be mixed in the lemon grass to make the effectivity
time longer.
2. In getting the extraction, make the boiling process longer to gather more extract
solution.
3. Make some revisions in the variables, by testing other organic plants which has a
property almost the same with the lemon grass.
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