EFFICACY OF ORIGANUM VULGARE EXTRACTS AS MOSQUITO REPELLENT
A Research Paper
In Partial Fulfillment of the Requirements in
Practical Research I
(Experimental Research)
By:
John Alvin Molina
Jona Mae Banquillo
Grade 11 HUMMS
December 2019
Effecacy of Origanum Vulgare Extracts as Mosquito Repellent

Chapter 1
INTRODUCTION OF THE STUDY
Background and Theoretical Framework of the Study
Mosquitoes are the vectors of many pathogens that continue to make a large
impact on human health. Current control measures for vector-borne infectious diseases
are under threat and new strategies, including genetic control, are urgently needed.
Genetic strategies to control mosquito-borne diseases include population suppression
and population replacement. Mosquito bites lead to a variety of mild, serious, and,
rarely, life-threatening allergic reactions. These include ordinary wheal and flare
reactions and mosquito bite allergies (MBA). The MBA, also termed hypersensitivity to
mosquito bites (HMB), are excessive reactions to mosquito bites that are not caused by
any toxin or pathogen in the saliva injected by a mosquito at the time it takes its blood-
meal. Rather, they are allergic hypersensitivity reactions caused by the non-toxic
allergenic proteins contained in the mosquito's saliva. Studies have shown or suggest
that numerous species of mosquitoes can trigger ordinary reactions as well as MBA.
These include Aedes aegypti, Aedes vexans, Aedes albopictus, Anopheles sinensis,
Culex pipiens, Aedes communis, Anopheles stephensi, Culex quinquefasciatus,

Ochlerotatus triseriatus, and Culex tritaeniorhynchus.[123] Furthermore, there is
considerable cross-reactivity between the salivary proteins of mosquitoes in the same
family and, to a lesser extent, different families. It is therefore assumed that these
allergic responses may be caused by virtually any mosquito species (or other biting
insect).
The mosquito bite allergies are informally classified as 1) the Skeeter syndrome,
i.e. severe local skin reactions sometimes associated with low-grade fever; 2) systemic
reactions that range from high-grade fever, lymphadenopathy, abdominal pain, and/or
diarrhea to, very rarely, life-threatening symptoms of anaphylaxis; and 3) severe and
often systemic reactions occurring in individuals that have an Epstein-Barr virus-
associated lymphoproliferative disease, Epstein-Barr virus-negative lymphoid
malignancy,or another predisposing condition such as Eosinophilic cellulitis or chronic
lymphocytic leukemia.
Aglalana Integrated School is a newly established school at Dumarao, Capiz. Fact
is that even though new, there are several cases of Dengue at the said school.
According to recent studies, organic repellents have higher and longer chances of
repelling mosquitoes. Though need some chemical compositions, the main ingredient
which is the extracted oil of Origanum Vulgare also known as Oregano, is considered as
an excellent antiseptic and insect repellent. It has some active ingredients such as

carvacrol, thymol, and a-terpinene reported being highly effective in repelling
mosquitoes.
Statement of the Problem and Hypotheses
Generally, this study aimed to explore the efficacy of extracted oil of Origanum
Vulgare in repelling mosquitoes.
Specifically, it sought to answer the following questions:
1. How long will the repellency of the extracted oil from Origanum Vulgare last?
2. Is there a difference in repellency between the organic repellent and
synthetic repellents?
3. On the scale of 1-10, How effective is the repellent?
In view of the aforementioned problems, the following hypotheses were tested:

1. The repellency lasts for 30 minutes up to 1 hour depending on how much
extracted oil was used.
2. The organic repellent has higher and longer chance of repelling
mosquitoes when extracted oil from Oregano is at high amount compared
to synthetic repellents.
3. The efficacy of the repellent made from extracted oil of Origanum Vulgare
on the scale of 1-10 is at 8 depending on the amount of oil used. Besides,
there are still room for improvement when added with a certain oil to help
the repellency last longer.

Significance of the Study
This study is essential to students, and other persons because it provides
ideas and better actions in learning much effective and safe ways on repelling
mosquitoes. This will help the students and other persons involve the
community to find and discover much effective ways on repelling mosquitoes
in a safe and organic way.
The results of this study may be beneficial to the following:
Students. The result of the study provides adequate information for the students
to create an organic repellent that has higher chances of repelling mosquitoes. It also
provides safety for students against blood-sucking mosquitoes.
Parents. The result of the study provides trust for the parents that they and their
children will be safe on mosquitoes and the effects of the repellent.
The community. The result of this study provides better understanding for the
people in the community that organic repellents provides not just safe but longer effect
and protection against mosquitoes.

Future Researchers. The result of this study will serve as a reference for future
researchers in order to conduct further studies regarding the efficacy of Oreganum
Vulgare as larvicide for mosquitoes and clarify the facts about it.
Definition of Terms
The following terms were given their conceptual and operational definitions for
the purpose of clarity and precision.
Effects - refer to a change that results when something done or happens; an event,
condition, or state of affairs that is produces by a cause. (Merriam-Webster Dictionary,
2019)
In this study, “effects” referred to the efficacy of extracted oil from
Oregano as repellent for mosquitoes.
Mosquitoes – a small flying insect that sucks blood of animals and people via small
channel that serves as their mouth. (Merriam-Webster Dictionary, 2019)

In this study, “mosquitoes” referred to the target of the organic repellent
made from Oreganum Vulgare extracts.
calculator as an independent variable being used.
Students - refer to a person who attends a school, college, or university; a person who
studies something. (Merriam-Webster Dictionary, 2019)
In this study, “students” referred to the persons who are the respondents of the
study.
Oregano – a culinary and medicinal herb containing active ingredients such as
carvacrol, thymol, and a-terpinene reported being highly effective in repelling
mosquitoes.
In this study, “Oregano” referred to the plant hthat was extracted to make
the organic repellent.
Repellent – a material with chemical compositions use to keep or drive something away
such as flies, mosquitoes, etc. (Merriam-Webster Dictionary, 2019)

In this study, “repellent” referred to the substance made out of Oregano
extract use to repel mosquitoes.
Extracts – to withdraw something, such as juice,by physical or chemical process.
(Merriam-Webster Dictionary, 2019)
In this study, “extracts” referred to the soluble substance removed from
the Oregano.
Chemical Composition – refers to the arrangement and ratio of atoms in molecules of a
substance. (Merriam-Webster Dictionary, 2019)
In this study, “Chemical Composition” referred to the composition of the
extract of Oregano used in making the repellent.

Delimitation of the Study
This study aimed to contrast the efficacy of the extract of Oreganum Vulgare as
a repellent for mosquitoes. This study aimed to take place at the home of the
researcher located at Barangay Aglalana, Passi City, Iloilo during the second semester
of the S.Y 2019-2020. The data gathering and experiment time targets the amount of
days at a minimum of 10 days and a maximum of 15 days. This amount of time is
required for the researcher to gather as much as information as he can to improve the
efficacy of the said repellent. Addition on materials and methods are allowed to have
better results for the experimental research that would be conducted by the researcher.
Any result either pro or con shall be recorded to allow further clarifications and
improvements on the study.

CHAPTER 2
REVIEW OF RELATED LITERATURE
Introduction
Mosquitoes are carriers of diseases causing serious health problems in tropical regions.
A variety of mosquito species transmit many diseases to humans and animals in a
species-dependent manner; for example, Aedes aegypti is the vector for dengue fever,
Zika fever and Chikungunya, Anopheles dirus B is a vector for malaria in Asian forested
zones and Culex quinquefasciatus is a vector for zoonotic diseases that affect humans
and wild and domestic animals. Almost all these diseases are severe problems in many
countries, which makes it necessary to control mosquito populations. Although there
are many mosquito pesticides available on the market currently, mosquitoes can
develop resistance to pesticides, especially synthetic pesticides, and thus, it becomes
necessary to increase the dosage used to control mosquitoes, introducing additional
risks to human health and to the environment.
From the past, the discovery and development of pesticides with mosquito larval
toxicity derived from plant extracts have become a topic of interest to many
researchers. At present, plant extract products are attractive choices for use in

integrated pest management programmes to reduce the residues in the environment as
it has biodegradable efficiency. Many studies have used plant extracts to control
mosquitoes.
This present study evaluated the use of rhizome Alpinia galanga, a herb in the
Zingiberaceae family that is commonly used in cooking, especially in Thai cuisines, to
control a certain species of mosquito larvae.
Repellency Effects of Plant Extracts
Pest management techniques are many and varied: mechanical, cultural, biological, and
chemical. Treatment of adult mosquitoes – adulticiding – is achieved entirely via
pesticide applications targeted to adult mosquitoes. The process of adulticiding is a step
wise process that often is considered the method of last resort in an Integrated Pest
Management (IPM) approach to mosquito control (Connelly 2012). Adult female of
certain mosquito species have the ability to transmit diseases from an infected
individual to a susceptible person. Vector control measures have, therefore, been
established to control the transmission of the disease by targeting the carriers. Over the
past few decades, the vector has however developed the ability to evade intervention
measures, which target adult mosquitoes, thus, exacerbating the problem for vector
control programmes (Sharp 1983). The current vector control technique involves the

use of residual repellents which are sprayed onto walls and roofs of houses. With
concern for the quality and safety of life and the environment, the emphasis on
controlling mosquito vectors has shifted steadily from the use of conventional chemicals
toward alternative repellents that are target-specific, biodegradable, and
environmentally safe, and these are generally botanicals in origin. Although plants and
their derivatives were used for controlling and eradicating mosquitoes and other
domestic pests before the advent of synthetic organic chemicals, only few insecticides
of plant origin have been found commercially available. Plant-derived bioproducts,
however, still have encouraging results in the control of mosquito vectors if they are
adequately effective and harmless to beneficial non-target organisms and the
environment. Furthermore, the insect resistance to mosquitocidal botanical agents has
not been documented (Shaalan et al. 2005).
A study of monoterpenoids showed that for topical acute toxicity on larvae the most
potent were thymol and carvacrol. The most profound synergistic effect was found in
the mixture p-cymene, thymol, carvacrol. (Roman Pavela, J Biopest, 2010, 3, 573-78).
The same author in another study found in laboratory conditions that the sublethal
application of thyme oil to the adults of the housefly significantly reduced their longevity
and the natality decreased by 80%, And even larvae which emerged from eggs from
female flyies which had been treated, were non vital. In a third study (R Pavela,
Phytother Research 2008, 22, 274-8) the same author studied the insecticidal activity of
34 essential oils extracted from plants and found those from Origanum vulgare,

majorana, compactum, Ocimum basilicum, Thymus vulgaris were lethal in doses in the
microgram range. The advantage of these plants is that they are easy to grow in many
countries and have well known nutritional values. Some of the terpenes, like carvacrol,
also have strong antiplasmodial properties.
Oregano oils are rich in thymol (38.8%), carvacrol (32.9%), p-cymene (7,9%). They
have strong toxicities against Rhizoperta dominica by contact or by fumigation (O Khalfi
et al., J Sc Food and Agricul, 2008, 9, 1562-66). Efficient also against drosophila (I
Karpouhtsis et al., J Agricult and Food Chem, 1998, 46, 1111-15). Thymol contributes
to the acaricidal properties of Ocimum gratissimum.
Repellent Bioassay
Repellents make humans unattractive to a mosquito so that it will avoid areas of the
body that have been treated with the products and they do not kill mosquitoes. Quality
repellents will provide protection from bites for a long period of time from just one
application. The use of repellents to protect humans and his animals from bites of
mosquitoes already has been accepted as part of an overall integrated mosquito-borne
disease control program (Chavasse and Yap 1997; Yap et al. 2000). The use of natural
products such as plant extracts or oils was not common until now due to many reasons.
Thus, it is now rather easy to find chemical compounds that have repellency properties

and to use them as active ingredients in a repellent product (Amer and Mehlhorn 2006).
Freeborn (1928) and Dover (1930) cited some insect repellent formulations consisting
of a number of essential oils such as citronella, camphor, tar, pennyroyal, and castor
oils that provided a long-lasting protection from insect bites. Repellents have an
important place in protecting man from the bites of insect pests. An effective repellent
will be useful in reducing man-vector contact and in the interruption of disease
transmission. Repellent compounds should be non-toxic, nonirritating and long lasting
(Kalyanasundaram 1991). Majority of commercial repellents are prepared by using
chemicals like allethrin, N-N-diehyl-m-toluamide (DEET), dimethyl phthalate (DMP) and
N, N-diethyl mendelic acid amide (DEM). It has been reported that these chemical
repellents are not safe for public use (Zadikoff 1979; Ronald et al. 1985). In the last
few years, with the increase of public concern on the safety of many chemical products
that were used previously as insecticides or insect repellents, several institutes and
researchers started development of natural active ingredients especially from plant
sources.
Synthesis
Mosquitoes are the most important single group of insects in terms of public health
importance. Mosquitoes not only cause nuisance by their bites but also transmit deadly
diseases. Among the approximately 4000 known mosquito species, less than 10% are

regarded as efficient vectors of pathogenic agents of infectious diseases having high
impact, both direct and indirect, on human welfare and health. Mosquito-transmitted
diseases remain a major cause of the loss of human life worldwide with more than 700
million people suffering from these diseases annually (Taubes 1997). Therefore,
repellency of mosquitoes is essential to help prevent serious health problems. Using the
extracted oil of Origanum Vilgare (Oregano) shows effective results of repellency effects
on mosquitoes as itshows 30 minutes up to an hour repellency on mosquitoes.
Preferring natural repellents to repel mosquitoes rather than synthetic enables the host
to be safe not just from host-seeking mosquitoes but also to health safety concerns.

Chapter 3
Methodology
Research Design
Experimentalresearchdesigniscentrallyconcernedwithconstructingresearchthatishighincau
sal(internal)validity.Randomizedexperimentaldesignsprovidethehighestlevelsofcausalvali
dity.Quasi‐experimentaldesignshaveanumberofpotentialthreatstotheircausalvalidity.Yet,n
ewquasi‐experimentaldesignsadoptedfromfieldsoutsideofcriminologyofferlevelsofcausalv
aliditythatrivalexperimentaldesigns.
Thedesignofresearchisfraughtwithcomplicatedandcrucialdecisions.Researchersmustdecid
ewhichresearchquestionstoaddress,whichtheoreticalperspectivewillguidetheresearch,how
tomeasurekeyconstructsreliablyandaccurately,whoorwhattosampleandobserve,howmany
people/places/thingsneedtobesampledinordertoachieveadequatestatisticalpower,andwhi
chdataanalytictechniqueswillbeemployed.Theseissuesaregermanetoresearchofalltypes(ex
ploratory,explanatory,descriptive,evaluationresearch).However,theterm“researchdesign”
typicallydoesnotrefertotheissuesdiscussedabove.

Theterm“experimentalresearchdesign”iscentrallyconcernedwithconstructingresearchthati
shighincausal(orinternal)validity.Causalvalidityconcernstheaccuracyofstatementsregardin
gcauseandeffectrelationships.Forexample,doesvariable1causevariationinvariable2?Ordoe
svariable2causevariationinvariable1?Ordoesvariable3causevariationinbothvariables1and2
?Andwhatisthemagnitudeofthecausalrelationshipsamongthevariables?Thus,researchdesig
nasusedhereinisaconcernofexplanatoryandevaluationresearchbutgenerallydoesnotapplyt
oexploratoryordescriptiveresearch.
Materials/Apparatuses and Utensils
These are the lists of materials, apparatuses and utensils used for the experiment.
Materials and Apparatuses. Quantity. Unit
Gardening gloves. 2. Pieces
Pillowcaseor any cloth. 1. Pieces
Hammer or Rolling Pin. 1. Pieces

Bucket or large bowl. 1. Pieces
Surgical-style face mask. 1. Pieces
Goggles. 1 Pieces
Dish soap. 100 Milliliters
Strainer. 1. Pieces
Spray bottle. 1. Pieces
Oregano. 50. Grams
Water. ½. Litters
Procedures and Methods

1.Put on a pair of gardening gloves and harvest about 4 to 5 cups of oregano leaves
and stems. Put the plant material in an old pillowcase. Harvest oregano after the buds
have formed, but before the flowers open, because this is when its oils are strongest.
2.Place the pillowcase on the floor, and smash it several times with a mallet, or run a
rolling pin over it to break up the leaves and stems and release the plant juices. Turn
the pillowcase over and continue breaking up the plant material with the bat or rolling
pin.
3.Open the pillowcase, turn it inside out and dump the plant material into a container,
such as a bucket or large bowl. Place the empty pillowcase in the container as well.
Then pour just enough water over the pillowcase and the crushed leaves and stems so
that they're fully submerged.
4.Place the container in a sunny area and let the mixture steep. Stir it several times
throughout the day and let it sit overnight.
5.Put on gloves, a surgical-style face mask, goggles, and clothes that cover your arms
and legs, and then, stir 1 teaspoon of liquid dish soap into the mixture so the plant oils

distribute throughout the water. Pour the mixture in a strainer that's placed on a clean
container. This separates the plant material from the water. Thoroughly wring out the
pillowcase over the container.
6.Fill the liquid in a labeled spray bottle and apply it on an insect invested plant to see if
it works. The dish soap in the liquid will act as glue that helps the mixture stick to the
plants. When the insects run for cover than you know the spray works