Nothing Special   »   [go: up one dir, main page]

The Larvicidal Effect of Sampaguita Leaf Extract On Mosquito Larvae

Download as docx, pdf, or txt
Download as docx, pdf, or txt
You are on page 1of 37
At a glance
Powered by AI
The key takeaways are that dengue is caused by the Aedes aegypti mosquito and cases have been increasing in the Philippines. Control measures aim to eliminate mosquitoes and their breeding places to reduce dengue transmission.

The main cause of dengue is a female mosquito known as Aedes aegypti which carries the dengue virus.

Efforts of control should be directed against the mosquitoes. It is important to take control measures to eliminate the mosquitoes and their breeding places.

1

CHAPTER I
Problem and its Background
Introduction
Dengue is a pandemic concern and it commonly affects the peoples health in
developing countries. Although advanced technology and medicines are now available,
cases of dengue are still rising up to date with outstanding numbers.
The Philippines have been a dengue fever hotspot for several years. During the first
quarter of 2011, The Philippine Department of Health reported that the incidence of
dengue fever doubled in Metro Manila. Compared to last years statistical record of
dengue cases in the Philippines, the 1,984 dengue case in 2010 has significantly increased
to 4,399 dengue cases during the same period in 2011. (Tubeza, Philip, DOH tags
dengue hot spots in Pasig, Valenzuela, April 14, 2011, www.inquirer.net,
http://www.inquirer.net/specialfeatures/denguealert/view.php?db=1&article=20110414331185)
The main cause of dengue is a female mosquito known as Aedes aegypti which carries
the dengue virus. Once the virus enters the human body, it puts the persons life at risk.
The Aedes aegypti usually breeds on areas with stagnant water and filthy damp places
such as discarded tires, flower vases and uncovered barrels.

Studies show that

mosquitoes are fast reproducing animals, thus preventing the population growth of the
larvae is the best way to lessen the alarming number of dengue cases.

Jasminum sambac is a bushy vine with dark green leaves and has fragrant little
flowers used as decorations that have aromatherapy purposes. It is well regarded as an
aphrodisiac and also considered as an antidepressant, sedative and antispasmodic.
It is a species of jasmine native to South and Southeast Asia and it is the national
flower of the Philippines. Jasminum sambac is abundant to the country especially in San
Pedro, Laguna.

Background of the Study


Dengue is an acute fever caused by a virus. It occurs in two forms namely, the (1)
dengue fever and the (2) dengue haemorrhagic fever. Dengue spreads rapidly and may
affect large number of people during an epidemic resulting in reduced work productivity,
but most importantly causing the loss of lives.
Dengue is spread by the bite of an infected female mosquito (Aedes aegypti). The
mosquito gets the virus by biting the infected persons. There is no way to tell if a
mosquito is carrying the dengue virus. Therefore, people must protect themselves from
all mosquito bites. All efforts of control should be directed against the mosquitoes. It is
important to take control measures to eliminate the mosquitoes and their breeding places.
However, the efforts should be intensified before the transmission season (during and
after the rainy season) and at the time of the epidemic.
In the year 1998, Philippines had its worst cases of dengue. This caused and started

the great alarm to the health of people living in the country. And until the present,
Filipinos are still in danger of the endemic disease here in the Philippines.

The

Department of Health reported that cases of dengue fever doubled in Metro Manila
during the first four months of the year 2011. The Philippines has been a dengue hotspot
for years and the cases are most alarming: 4,399 cases in 2011 while 1,984 cases in 2010.
The Department of Health cited Manilas Barangay San Miguel in Pasig City and
Barangays in Valenzuela as particularly high risk areas.
There is no specific medicine for the treatment of the disease. For this reason, this
research study is to be conducted to produce an effective way of lessening the greater
risks of dengue by using the larvicide produced from an organic compound found in the
Sampaguita leaf to kill the larvae of mosquitoes.

Theoretical Framework
Reinfestation, aggravation of the dengue situation, economic difficulties, and
knowledge deficit are the threats of the urbanization of dengue fever, thus it continues the
cycle of dengue fever and number of dengue cases started to increase again. Based on
Carlo J. Finlay and Dr. Juan Guiteras theory which says that the infection was
transmitted from person to person through the bite of the mosquito, the basis of this study
is to have effective measures in controlling the disease first by preventing the population

growth of Aedes aegypti which carries the dengue virus by eradicating the mosquito
larvae using the leaf extract of Sampaguita (Jasminum sambac) as a larvicide.
The Sampaguita or Jasminum sambac have the constituents of alkaloids, glycoside,
flavanoid, terpines, tannin, resin and salicylic acid.
The Sampaguita contains alkaloids that are highly poisonous and can have a
pharmacological effect on animals. (Mo Li Hua. Sampaguita, Philippine Medicinal
Plants. October 2010. http://www.stuartxchange.org/Sampaguita.html) Because of this,
there might be a possibility that the Sampaguita (Jasminum sambac) can help in
preventing further growth of Aedes aegypti.

Conceptual Framework

INPUT
-Nature of Sampaguita
leaves
containing
Alkaloid
-Aedesa egypti larvae

PROCESS
-Crude
method

extraction

-Testing
the
leaf
extract
on
Aedes
aegypti
larvae
to
determine its larvicidal
property
and
effectiveness.

OUTPUT

Jasminum
sambac
crude leaf extract as
an effective larvicide
against
Aedes
aegypti.

Figure 1.1 A paradigm showing the conceptual framework of the study

First, the researchers would have the Sampaguita leaves with the Aedes aegypti larvae
for the extraction and experimentation process. In the Process table, the researchers have
the crude extraction method to take out the leaf extract from the Sampaguita leaf.
Afterwards, the researchers would look forward to having an effective larvicide against
Aedes aegypti larvae.
This paradigm would be followed during the whole study and will be used as the guide in
continuing with this study.

Statement of the Problem


Main Problem:
Does the leaf extract of Jasminum sambac contain effective larvicidal property?
The following questions will be answered by the end of this research:
1. What are the effects of the crude leaf extract to Aedes aegypti larvae?
a. In terms of the mortality rate
b. In terms of time of effectivity
b.1) after 15 minutes
b.2) after 30 minutes
b.3) after 60 minutes
b.4) after 120 mintues
c. In terms of the concentration of the extract
c.1) 1 ppm
c.2) 10 ppm
c.3) 100 ppm
c.4) 1000 ppm

Assumptions
A solution to one of the alarming dangers in the Philippines which is the dengue is the
production of efficacious larvicides. In this study, Jasminum sambac contains glycosides
and alkaloid that can be used as larvicides which can prevent the greater risks of dengue;
therefore, lessening the cases regards to the loss of life. There are also specific methods
to extract the required organic compounds from the said plant material to produce an
effective larvicide. The larvicidal property of the Jasminum sambac will greatly affects
the population growth of the mosquito, causing high mortality rate. Aedes aegypti,
resulting to a safer place to live in.

Hypothesis
Null Hypothesis: The Jasminum sambac leaf extract has no significant effect on Aedes
aegypti larvae.
Alternative Hypothesis: TheJasminum sambac leaf extract has a significant effect on
Aedes aegypti larvae.

Significance of the Study


The aim of the study is to make use of the larvicidal property of Sampaguita
(Jasminum sambac) leaves as an effective larvicide. The larvicide would be preventing
the population growth of Aedes aegypti larvae that carries Dengue. The number of

Dengue cases according to the Department of Health is 1,984 last year to 4,399 this year
and the number of deaths caused by this disease is already 77 only in Metro Manila. This
research study is efficient and is one of the best ways in preventing dengue that may
benefit the whole community.

Scope and Limitations of the Study


The study is focused on testing the larvicidal property of Sampaguita (Jasminum
sambac) leaves and its effect to Aedes aegypti larvae. The Jasminum sambac leaves
would be gathered from San Pedro, Laguna. The Sampaguita leaf extract would be
extracted by using an electric blender to pulverize then a Soxhlet extractor to take out the
alkaloid from the powder and afterwards to be placed in a petri dish. The larvicide would
be sprayed in different amounts in four setups containing not less than 15 female
mosquito larvae. The Aedes aegypti with the larvicide would be exposed for 24 and 48
hours. The study would last for about two to three months.
The emphasis is not to cure Dengue fever but rather to help in preventing the
population growth of the Aedes aegypti.

Definition of Terms
Alkaloids. It is a chemical compound that is considered most powerful and effective
among all elements found in plants. Its effectiveness commonly includes all substances
that are poisonous in the plants. Alkaloids are derived from amino acids and include an

enormous number of bitter, nitrogenous compounds according to R.F. Raffauf (Plant


Alkaloids: A Guide To Their Discovery and Distribution, 1996). Alkaloids are considered
to be disintegrate substances that comprise proteins.
Dengue fever.an acute infectious disease transmitted by Aedes aegypti mosquitoes,
and characterized by headache, severe joint pain, and a rash. (Dengue. MerriamWebsters Collegiate Dictionary. 10th ed. 2001.)
Dengue Haemorrhagic fever.It is a severe, potentially deadly infection spread by
certain species of mosquitoes (Aedes aegypti). Bleeding and sometimes shock occurs
leading to death. (Vaughn DW, Barrett A, Solomon T. Flaviviruses (Yellow Fever,
Dengue, Dengue Hemorrhagic Fever, Japanese Encephalitis, West Nile Encephalitis, St.
Louis Encephalitis, Tick-Borne Encephalitis). In: Mandell GL, Bennett JE, Dolin R, eds.
Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier
Churchill Livingstone; 2009:chap 153.)
Dog Heartworm.(Dirofilaria immitis), a disease common in canines caused by a
nematode. (Does Your Dog Have a Heartworm? (Crans, W. Does Your Dog Have A
Heartworm?Rutgers.

Retrieved

February

1,

2012,

from

www-

rci.rutgers.edu/~insects/hartw.htm)
Epidemic. Affecting a disproportionally large number of individuals within a
population or community. (Epidemic. Merriam-Websters Collegiate Dictionary. 10 th
ed. 2001.)
Larvae. It is an immature, wingless, and often vermiform feeding form that hatches
from the egg of a many insects, increases in size, undergoes other minor changes while
passing through several molts, and is finally transformed into a pupa or chrysalis from

which the adult ultimately emerges.(Larva. Merriam-Websters Collegiate Dictionary.


10th ed. 2001.)
Larvicide. It is an insecticide or other pesticide used for killing larvae. (larvicide.
Merriam-Webster.com. 2011. http://www.merriam-webster.com. February 1, 2011).
Murray Valley. It is a rare disease caused by the Murray Valley encephalitis virus. It is
spread to humans by infected mosquitoes. (March 2, 2011. Murray Valley Encephalitis,
NSW

Government,

Health.

Retrieved

February

11,

2012,

from

http://www.health.nsw.gov.au/factsheets/infectious/murray_valley_enceph.html)
Pandemic. It is occurring over a wide geographic area and affecting an exceptionally
high proportion of the population. (pandemic. Merriam-Websters Collegiate
Dictionary. 10th ed. 2001.)
Ross River virus. It is a germ that infects people, particularly in rural areas, sometimes
causing a flu-like illness with joint pains, rash and fever. (January 16, 2008. Murray
Valley Encephalitis, NSW Government, Health. Retrieved February 11, 2012, from
http://www.health.nsw.gov.au/factsheets/infectious/rossriver.html)
Sampaguita. (scientific name Jasminum sambac) It is a species of the genus jasmine
and is widely grown as an ornamental plant. This species is native to southern Asia, India
and Sri Lanka.(Sampaguita.The Flower Expert. Retrieved February 11, 2012, from
http://www.theflowerexpert.com/content/aboutflowers/tropicalflowers/sampaguita)
Vaccine. It is a biological preparation that improves immunity to a particular disease.
A vaccine typically contains an agent that resembles a disease-causing microorganism,
and is often made from weakened or killed forms of the microbe.(vaccine. MerriamWebster.com. 2011. http://www.merriam-webster.com. February 1, 2011).

10

CHAPTER II
Review of Related Literature and Studies
Related Literature
Foreign Literature
Dengue is an epidemic disease that occurs on warmer climates caused by a virus transmitted by the mosquito, Aedes aegypti, which also spreads yellow fever. In Southeast

11

Asia, a severe form of the ailment called dengue haemorrhagic fever has caused
numerous deaths for the past few years. (Dengue fever, Grolier Academic
Encyclopedia, 1988)

The tiger mosquito or Aedes aegypti, is a species that breeds in

artificial containers found in houses. This type of insect bites on its hosts during daytime.
Aedes aegypti is the vector of urban yellow fever and dengue. This species are associated
with the transmission of the viral haemorrhagic fevers, of Southeast Asia.
The female Aedes aegypti has mouthparts modified for sucking blood from its hosts.
The female mosquitoes need it in order to mature its eggs. In dengue virus infected
mosquitoes, the virus is present in the salivary glands of the mosquito. When a female
Aedes aegypti bites a human for food, she injects saliva into the wound where the anticoagulants contained in her saliva facilitate feeding. (Aedes aegypti, Dengue Virus Net,
http://www.denguevirusnet.com/aedes-aegypti.html)
Most mosquito species spend much of their life cycle in larval stage when they are
highly susceptible to both predation and control efforts. They often are concentrated
within defined water boundaries, immobile with little ability to disperse, and accessible.
Larvae feed on organic particulate matter in the water like algae. As long as the
temperature is cool, the Aedes aegypti larvae can remain in its larval stage for months.
(Life Cycle of Aedes aegypti, Dengue Virus Net, http://www.denguevirusnet.com/lifecycle-of-aedes-aegypti.html) Adult mosquitoes, on the other hand, fly in search of males,
blood meals, or water sources for egg laying and are usually inaccessible, not
concentrated, and highly distributed.

12

There are several theories regarding alkaloids stating that this type of element is a byproduct of plant-metabolism; that they are means of protection of plants against animal
and insect attacks; or that they are reservoirs for protein synthesis, regulators of growth
and reproduction, or detoxifying agents. (Alkaloids, Grolier Academic Encyclopedia,
1988) This element has a major positive effect on the intensity of making a larvicide. A
larvicide, on the other hand, is a chemical used for killing larvae.
Larvicides are chemicals used to kill mosquito larvae. Larvicides are more effective
in controlling mosquitoes because they kill mosquitoes before they become adults.
(Larvicides, Fair Harbor, http://www.fairharbor.com/fhca/ca2409larvicides.htm) The
larval stage of a mosquito would be its weakest point. Therefore, effective larviciding can
reduce the number of mosquitoes available to disperse, potentially spread diseases and
lay eggs which leads to more mosquitoes. (Larvicides and Larviciding, Mosquito
Information Website, http://mosquito.ifas.ufl.edu/Larviciding.html, 29 September 2011)

Local Literature
Dengue has been seizing headlines again in various local papers and publications in
Asia about another outbreak in the Philippines and a predicted upcoming outbreak which
would be much worse than that of 1998, where there were more than 38,000 cases.
(2011 Dengue Outbreak., Biotech Philippines, http://www.biotech.ph/2011-dengueoutbreak, 29 September 2011)

13

The mosquitos bullet-shaped eggs are singly laid and are without floats. The tiger
mosquito lays its eggs in any type of water, mainly in polluted areas.
Larval development is affected critically by the presence of adequate moisture and
surrounding vegetation, light intensity, salinity or alkalinity of the aquatic medium, and
temperature.
Mosquito control is largely a matter of familiarity with the biological and ecological
requirement of the target species whenever possible. (Baltazar, Clare and Salazar, Nelia;
Philippine Insects an Introduction, Diliman, Quezon City, University of the Philippines
Press, 1979)
Sampaguita (Jasminum sambac) or Kampopot, a climbing shrub with white flowers,
usually with a double corolla, which has a delightful fragrance and native to southern
Asia, contains a powerful element called alkaloid. (Steiner, Mona Lisa, Philippine
Ornamental Plants and Their Care, Manila, Philippines. 1992)

Related Readings
The related readings tell about the certain topics such as administrative orders, health
programs, campaigns and ordinances concerning dengue prevention and control. Thus,
using the full knowledge acquired can help in the process of preventing such epidemic
disease to worsen. The alarming number of dengue cases serves as a wake-up call to
everyone that we must prevent and control the spread of dengue.

14

The Administrative order no. 281 of 1996 entitled The National Tepok Lamok and
Dengue Sapok Program explains about the prevention of the spread of dengue virus by a
Nationwide clean-up drive operation and elimination of mosquito breeding places in
Observance of the Four Oclock Habit with the participation of the National Agencies
and Local Government Units particularly the Department of Health that leads this
project.1
Though the ordinance stated above is a good way to prevent the massive effect of the
dengue virus, it is still not good enough to say that we are safe from being affected by this
disease. Mosquitoes are fast reproducing insects and cleaning our surroundings wont be
enough to stop the spread of dengue.
According to the Administrative order no. 45 of 2001, The Aedes aegypti mosquitoes
are container-breeders. Aedes aegypti could breed in any container that can hold water.
Plastic bottles, tin cans and plastic cans can easily be disposed but pails, plastic drums
and flower pots are usually used in our homes may require chemical larviciding which is
on a long-term basis but it have the best result in situations where the location and period
at risk is indicated or specified.
Larvicide application is more beneficial because of the fact that the mosquitoes are
destroyed before they mature and disperse to human habitation that can cause massive
effects especially to every individuals health. It can also be done at home and can obtain
fast results.2

1 Administrative Order no. 281 s. 1996, 07/19/98, Department of Health, 09/29/11,


http://www.chanrobles.com/administrativeorders/administrativeorderno281%201996.html

15

Related Studies
Foreign Studies
The researchers primarily choose this research proposal because of its significance to
the common problems in the community and the increasing number of dengue cases is
one of them. The researchers were able to find out that there are studies that are
interconnected with the present study that will serve as the basis of this research proposal.
The research proposal derived its extraction process from the study in India by Kumar,
Naresh et. Al about Carica Papaya leaf extract being an effective larvicide. It similar to
the current study except that they used Papaya leaf extract as the independent variable.
The extraction process is to use the soxhlet extractor to extract the crude from the leaves
of the Carica Papaya. The plant extract showed larvicidal and pupicidal effects after 24 h
of exposure; however, the highest larval and pupal mortality was found in the leaf extract
of methanol C. papaya against the first- to fourth-instar larvae and pupae of values
LC(50)=I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and
IV instar was 82.18 ppm, and pupae was 440.65 ppm, respectively, and bacterial
insecticide, spinosad against the first to fourth instar larvae and pupae of values LC(50)=
I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and IV instar
was 82.18 ppm, and pupae was 93.44 ppm, respectively. Moreover, combined treatment
of values of LC(50)=I instar was 55.77 ppm, II instar was 65.77 ppm, III instar was

2 Administrative Order no. 45 s. 2001, 08/16/01, World Health Organization,


09/29/11/,http://www.doh.gov.ph/files/ao45-01.pdf

16

76.36 ppm, and IV instar was 92.78 ppm, and pupae was 107.62 ppm, respectively. No
mortality was observed in the control. The results that the leaves extract of C. papaya and
bacterial insecticide, Spinosad is capable of being effective larvicidal and pupicidal
properties of against chikungunya vector, A. aegypti. Since the study will also be using
the same plant part in which the crude will be extracted from, the researchers will use this
study as the basis for its experimentation process.
The study of Priya Joy and Dr. D. Patric Raja entitled Anti-Bacterial
Activity Studies of Jasminum grandiflorum and Jasminum sambac on
the year 2008 in India, gives way in strengthening the foundation of
the research proposal because of its phytochemical analysis on
Jasminum Grandiflorum and Jasminum Sambac.
Phytoconstituents
Alkaloids
Tannin
Flavanoid
Steroid
Glycoside
Terpenes
Resin
Salicylic acid

Jasminum sambac
+
+
+
+
+
+
+
+

Table 3.1 Phytochemical Analysis on Jasminum Sambac

17

The table above shows that Jasminum sambac is positive in


containing alkaloid and glycoside which are effective ingredients in
making larvicide. Alkaloid is said to be an effective constituent for a
larvicide according to a study by Ferdinand M. Talontsi, Josphat C.
Matasyoh, et. Al. entitled Mosquito Larvicidal Activity of Alkaloids from
Zanthoxylum lemairei against the Malaria Vector Anopheles gambiae
which was conducted in Germany on November 2010.

The study

shows that the West Cameroon (Zanthoxylum Lemairei) which contains


alkaloid that was used as a larvicide in the study, had a high mortality
rate effect on the larvae. Which means that alkaloid is an effective
constituent larvicide.

Local Studies
The researchers based the concentrations of the extracts on the
study entitled The larvicidal effect of Guyabano (Annona muricata)
leaf extract on Aedes aegypti mosquito by Tangga-an, Hie Loren in
Cebu on 1999 in which used 1 ppm, 10 ppm, 100 ppm, and 1000 ppm
as its concentration that obtained the following mortality rates as the
result of the study: 1000 ppm = 0.61; 100 ppm. = 0.403; 10 ppm =

18

0.203; 1 ppm = 0.10 and concluded that the Guyabano leaf extract
exerted larvicidal effect on the two-day old Aeges aegypti larvae with
the higher concentration exerting greater potency.
The period of time of recording the results of the research is based
on a study in the Philippines during 1993-1994, entitled The larvicidal
effects of neem tree (Azadirachta indica) leaf and seed extracts on
mosquito larvae (Second year school year 1993-1994) by P. Padilla in
which the researcher used the said extracts for different periods of
time: 15 minutes, 30 minutes, 60 minutes and 120 minutes. After
three replicates with a maximum period of two hours, results showed
an increasing larvicidal effect as the concentration of the Neem extract
from both seed and leaf is increased. For the positive control, a 100%
larvicidal effect was observed 15 minutes after the time of application.
In this study, the researchers are to investigate if Jasminum sambac has larvicidal
property. Subsequent the investigations above, Jasminum sambac may contain larvicidal
property that can be beneficial in preventing diseases specifically Dengue.

Justification of the Study


Many approaches have been developed to control the mosquito threats. One approach
is killing the mosquito at larval stage. In this study, Sampaguita Jasminum sambac leaf

19

extract is to be tested whether it is an effective larvicide to mosquitoes specifically Aedes


aegypti. The study is distinct with the other studies because it has the same subject matter
and it both aims to make use of an extract from a plant to be made into a larvicide. Based
on the given related studies, the phytochemical analysis of the Jasminum sambac callus
extract, it is shown that alkaloid is present.
Studies have shown that some plant extracts like the ones mentioned in the related
studies contain larvicidal property. These plant extracts from different parts of the plant
contain alkaloids and glycosides that can be made as a larvicide. There is also a study
showing twelve plants tested for having larvicidal property but Jasminum sambac is none
of the listed tested plants.

Larvicidal application is more beneficial than the other

methods in controlling Aedes aegypti because it shows more accurate and effective
results because it inhibits the growth of the larvae thus makes it unable to grow fully into
a mosquito and spread the dengue virus to humans.
The related literature and studies proves that the research proposal is not a duplicate of
any other study.

20

CHAPTER III
Research Methodology
Research Design
In order to test the effectiveness of the Sampaguita leaf extract which is the treatment
to be applied to the mosquito larvae, different levels of the extract must be tested upon
sets of larvae. Since there is only one treatment but has different levels, without a control
group, the completely randomized design will be used.
The amount of the larvae must be observed first before applying the treatment.
Replications of the sets of larvae will be made for each level of treatment to reassure the
accuracy of the treatments effect. The containers with larvae are observed repeatedly
and will be recorded. If a change in the amount of the mosquito larvae is seen, then it can

21

be a strong evidence to the larvicides effectiveness. When the experiment is done after
several observations, data will be collected.
Random
Selection

180 Aedes
aegypti larvae

Treatment

Posttest

Set-up A =15 larvae/1 ppm


(with 3 replicates)
Set-up B= 15 larvae/10 ppm
(with 3 replicates)
Set-up C= 15 larvae/100 ppm
(with 3 replicates)
Set-up D= 15 larvae/1000 ppm
(with 3 replicates)

Number of dead larvae


In set-up A
Number of dead larvae
In Set-up B
Number of dead larvae
In Set-up C
Number of dead larvae
In Set-up D

Table 3.2 The table shows the research design to be used.


In order to see the effectiveness of the larvicide, data is charted. Afterwards, the
differences between each set of containers are observed. If there is a clear distinction
between the amounts of larvae from the others, then an inference would be much easier to
come up on.

Determination of Sample Size


There will be a number of treatments each with different levels of concentration of the
extract from the Sampaguita leaf. These treatments will be applied to containers with
larvae. Each petri dish contains fifteen larvae. There will be three replicates for each
container assigned to a certain level of treatment to determine the differences of each

22

result accurately. In total, there would be 180 Aedes aegyptilarvae. The researchers may
form an unbiased conclusion.
A large sample size will make the records homogeneous. This type of data will make
accurate statistical treatments with small amounts of values.

Sampling Design and Technique


The researchers will use probability sampling technique to obtain unbiased results.
The researchers will use the method of lottery sampling to set each petri dish, containing
15 larvae, to its corresponding set. Afterwards, each set will be paired to a different level
of treatment.
The Subject
The subject to be used in this study is the mosquito larvae that carries dengue virus,
which is known as the Aedes aegypti. The Aedes aegypti, a female mosquito is
recognized as a small, dark mosquito with white markings on their legs. This type of
mosquito breeds on stagnant waters and filthy damp places. The mosquito carries other
diseases rather than just dengue.
The Aedes aegypti larvae may be obtained through ovicidal traps, breeding and
gathering the subject. The population of Aedes aegypti are decreased by the extermination
of its larvae for further growth.

23

The Research Instrument


The researchers would be using a research instrument to record and gather the data
needed in the experiment. This research instrument would be in the form of observation
sheets that would be used during the experiment. It would contain the results of the
experiment.
The researchers chose to have four concentrations with three replicates under each
concentration. The first column would contain the factors to be considered during the
experiment. In the next columns, records about the four concentrations; 1 ppm, 10 ppm,
100 ppm and 1000 ppm would be shown. Thus, the evaluation of the study would be
more organized and efficient with the help of the research instrument.
Validation of the Research Instrument
The research instrument must be validated and revised first by the research teacher
before using it during the experiment. The revised research instrument includes the
suggestions to secure the legitimacy of the instrument. This would give a possibility for
the experiment to be more specific and accurate.

Procedures, Materials and Equipments


The researchers would be using Jasminum sambac leaves as the independent variable
of this study. Sampaguita leaves would be available in San Pedro, Laguna wherein the
plant is abundantly found. The Aedes aegypti larvae would be the population of this
research. The larvae to be tested must be approximately 180. The larvae would be

24

collected from stagnant waters and afterwards would be brought to a laboratory and thus
the larvae would be tested whether it is Aedes aegypti or not. The study would last for
about two to four months.
The procedure would begin with the crude extraction method. The extraction method
would be starting from washing the Sampaguita leaf with tap water. Then, leave it to dry
wherein the room temperature is about 24 to 28 C. When the leaf is dried, place it in an
electrical blender to pulverize. Soxhlet extractor would be used to extract alkaloid from
the powder. The Soxhlet extractor is a flask and condenser device for the continuous
extraction of alcohol or either soluble materials (Soxhlet extractor. Mcgraw Hill
Dictionary of Scientific and Technical Terms. 2003 Sixth Edition)
The pulverized Sampaguita leaves are placed inside a "thimble" made from thick filter
paper, which is loaded into the main chamber of the Soxhlet extractor. The Soxhlet
extractor is placed onto a flask containing the extraction solvent. The Soxhlet is then
equipped with a condenser. The solvent is heated on a traditional hotplate to reflux. The
solvent vapour travels up a distillation arm, and floods into the chamber housing the
thimble of solid. The condenser ensures that any solvent vapour cools and drips back
down into the chamber housing the solid material.
The chamber containing the solid material slowly fills with solvent. Some of the desired
compound will then dissolve in the solvent. When the Soxhlet chamber is almost full, the
chamber is automatically emptied by a siphon side arm, with the solvent running back
down to the distillation flask. During each cycle, a portion of the non-volatile compound
dissolves in the solvent. After many cycles the desired compound is concentrated in the
distillation flask. The advantage of this system is that instead of many portions of solvent being

25
passed through the sample, just one batch of solvent is recycled. After extraction the solvent is
removed, typically by means of an evaporator, yielding the extracted compound. The non-soluble
portion of the extracted solid remains in the thimble, and is usually discarded. (Soxhlet
extraction

procedure.

Cgerhardt.co.uk.

2011.

http://www.cgerhardt.co.uk/pages.php?

page_id=36. February 18,2012).

There would be four concentrations with three replicates of each petri dish. In each
petri dish, there would be 15 larvae. After the extraction, the larvicide would be placed in
the petri dish and the larvae would be exposed to different concentrations; 1ppm, 10 ppm,
100 ppm and 1000ppm. Having different concentrations would indicate the difference
and the effectiveness of the larvicide. The changes would be observed every 15, 30, 60
and 120 minutes. Afterwards, the data would be recorded and analyzed. Then a conclusion would be formed.

Collect sampaguita leaf


and Aedes aegypti larvae

Record the results based on how


many larvae died and lived after 24
hours and 48 hours of larvicide
exposure

Wash the Sanpaguita leaf


collected and shade-dry in
a room temperature.

Use the crude extract as a


larvicide to the set-ups.

Figure 3.1 A flowchart showing the procedures

Using an electrical
blender, powderize the
dried Sampaguita leaf.

Extract the Sampaguita crude


from the powderized leaf
using a Soxhlet extractor

26

Data Gathering Procedure


The larvicidal property of Sampaguita leaf extract requires experimentation as the data
gathering procedure. The researchers would be conducting an experiment to test whether
the Sampaguita plant contains alkaloid which will be used as a larvicide for mosquitoes.
The researchers would be collecting data through observation sheets which are based on
the experiment conducted. Through these observation sheets, the researchers will be able
to gather the data needed for the completion of the problem.

Data Processing Method


After performing the procedure, the data will be tabulated in a matrix. The measure of
the mortality rate of each container with mosquito larvae will be recorded after the analy
sis.
Afterwards, the mean percentage larval mortalities of Sampaguita leaf extract is
shown in the figure below.
Table 3.3 Mean % larval mortalities induced by leaf extract of Sampaguita (Jasminum
sambac) on the late third instar larvae of Aedes aegypti every 15, 30, 60 and 120 minutes

27

Treatment

Mean % Mortality
M1 after 15 minutes

1 ppm concentration

M1 after 30 minutes
M1 after 60 minutes
M1 after 120 minutes
M2 after 15 minutes

10 ppm concentration

M2 after 30 minutes
M2 after 60 minutes
M2 after 120 minutes
M3 after 15 minutes

100 ppm concentration

M3 after 30 minutes

M3 after 60 minutes
M3 after 120 minutes
M4 after 15 minutes
M4 after 30 minutes
1000 ppm concentration
M4 after 60 minutes
M4 after 120 minutes
Then statistical treatments will be applied to the data.

Statistical Treatment of Data


The statistical technique that the researchers will use to treat the research data for in

depth solution of problems in the study is the F-test with

MS b
MS w

as its main equation.

First, the researchers would have to write the hypothesis: the null and the alternative.
Next is to find the critical value in which you will base on whether to reject or accept the
null or alternative hypothesis. After finding the critical value, conduct the test. For this

28

problem, the researchers would be using F-test. For the f-test, raw should be computed in
which the values of the raw score will be needed to determine the sum of N for each
group, the total N, and the sum of the raw scores. Next, compute for the sum of squares,
the degree of freedom and the mean of squares. Then determine the significance of the Fratio. F-test is used in this problem to determine the differences of the means of the 4
different concentrations of Jasminum sambac leaf extract on the 4 set-ups of petri dishes
with 15 Aedes aegypti larvae. By determining this, the researchers will be able to make a
conclusion on whether the null hypothesis formulated should be accepted or rejected.

BUDGETARY REQUIREMENT
Needs
Materials and Equipments
Laboratory Expenses
Transportation
Other Expenses
TOTAL

Cost
4,500
6,500
750
1,000
12,750

29

SCHEDULE OF ACTIVITIES
SY 2011-2012
Au
g
1. Gathering of Aedes
aegypti larvae and
Sampaguita leaves
2. Experimentation
3. Observation
4. Analysis

Sept

Oct

Nov

Dec

Jan

Feb

30

5. Presentation of the
Final Research paper
6. Recommendations

BIBLIOGRAPHY
A. Books
Alkaloids. (1988) Grolier Academic Encyclopedia.
Baltazar, Clare and Salazar, Nelia. (1979) Philippine Insects an Introduction. Diliman,
Quezon City. University of the Philippines Press.
Dengue fever. (1988) Grolier Academic Encyclopedia.
Gallo, Romulo. (1984) The Philippine Journal of Science. De La Salle University. 361370.

31

Steiner, Mona Lisa. (1992) Philippine Ornamental Plants and Their Care. Manila,
Philippines.

B. Internet Sites
Tubeza, Philip. (2011, April 14). DOH tags dengue hot spots in Pasig, Valenzuela.
Inquirer. From http://www.inquirer.net/specialfeatures/denguealert/view.php?
db=1&article=20110414-331185
2011 Dengue Outbreak. Biotech Philippines. From http://www.biotech.ph/2011-dengueoutbreak
Administrative Order no. 281 s. 1996. (1996) Chan Robles Virtual Law Library.
Retrieved September 29,2011. From
http://www.chanrobles.com/administrativeorders/administrativeorderno281%201996.htm
l
Administrative Order no. 45 s. 2001. (2001). Department of Health. Retrieved September
29 2011. From http://www.doh.gov.ph/files/ao45-01.pdf
Mo Li Hua. Sampaguita, Philippine Medicinal Plants. Stuartxchange. Retrieved October
2010. From http://www.stuartxchange.org/Sampaguita.html
Larvicidal effects of Jatrophacurcas L. against Anopheles arabiensis (Diptera:
Culicidea). Petros. Retrieved November 11, 2011. From
http://www.mu.edu.et/mejs/pdfs/v3n1/Zewdneh.pdf
Larvicide. The Free Dictionary. From http://www.thefreedictionary.com/larvicide
Steps of the Scientific Method. Retrieved November 27, 2011. From
http://www.experiment-resources.com

32

Dundas Data Visualization, Inc. and others. (2001-2009) ANOVA Formula. Retrieved
2009. From http://support2.dundas.
com/OnlineDocumentation/WinChart2005/Anova.html
Life

Cycle

of Aedes Aegypti.

Dengue

Virus

Net.

Retrieved

2010.

From

http://www.denguevirusnet.com/life-cycle-of-aedes-aegypti.html

APPENDIX A
Sample Cover Letter
______________
______________
______________
______________
______________
______________
______________
______________

Dear (Madam/ Sir) __________,


Research I is one of the subjects in Makati Science High School. In this subject, students
are required to pass a research proposal and perform various experiments afterwards.

33

The researchers are conducting a study about the LARVICIDAL PROPERTY OF THE
Jasminum sambac LEAF EXTRACTS ON Aedes aegypti larvae. This would require the
researchers to ask your participation in this study through answering the observation
sheets needed in the experiment. The observation sheet is needed to gather data about the
ongoing experiment. The investigators would maintain the privacy of your personal
information. The students performing the study are hoping for your kind consideration
and cooperation.
We are grateful for your kind response to our request. If you would be involved, we
would gladly forward you the results of the dissertation.
Very truly yours,
The researchers,
Glory Tolentino
Samantha Bismonte
Marian Boneo

APPENDIX B
Observation Sheet
NAME: __________________________________________ DATE: ________________
Concentration

Concentration

Concentration

Concentration

1ppm

10 ppm

100 ppm

1000 ppm

Factors to be
considered
Time of
exposure upon
application
Time of
effectivity

34

Mortality rate

CURRICULUM VITAE
Personal Information
Name: Marian H. Boneo
Birth Date: January 11, 1998
Birth Place: Makati City, Metro Manila
Parents: Sylvia H. Boneo
Antonio D. Boneo
Educational Information
Year: 2010-Present
Course: High School
School: Makati Science High School
Year: 2004-2010
Course: Grade School
School: Cembo Elementary School
Work/Research Agencies:
Year Employed: 2011-2012

35

Position: Researcher
Agency: Makati Science High School
Honors/Awards Received:
Honors: First Honors (Cembo Elementary School)
Research Conducted
The Larvicidal Property of Sampaguita Jasminum sambac Leaf Crude Extract on
Mosquito larvae (Aedes aegypti) with Glory Grace M. Tolentino and Samantha Ally V.
Bismonte

CURRICULUM VITAE
Personal Information
Name: Samantha Ally V. Bismonte
Birth Date: March 28, 1998
Birth Place: Binan, Laguna
Parents: Maria Alma Lynn V. Bismonte
Sam B. Bismonte
Educational Information
Year: 2010-Present
Course: High School
School: Makati Science High School
Year: 2004-2010
Course: Grade School
School: Ann Arbor Montessori Learning Center Binan
Work/Research Agencies:
Year Employed: 2011-2012

36

Position: Researcher
Agency: Makati Science High School
Honors/Awards Received:
Honors: Second Honorable Mention (Ann Arbor Montessori Learning Center)
Research Conducted
The Larvicidal Property of Sampaguita Jasminum sambac Leaf Crude Extract on
Mosquito larvae (Aedes aegypti) with Marian H. Boneo and Glory Grace M. Tolentino

CURRICULUM VITAE
Personal Information
Name: Glory Grace M. Tolentino
Birth Date: March 26, 1997
Birth Place: Quezon City, Metro Manila
Parents: Chonalyn M. Tolentino
Gregory R. Tolentino
Educational Information
Year: 2010-Present
Course: High School
School: Makati Science High School
Year: 2004-2010
Course: Grade School
School: St. Bridget School QC
Work/Research Agencies:
Year Employed: 2011-2012

37

Position: Researcher
Agency: Makati Science High School
Honors/Awards Received:
Honors: First Honor (St. Bridget School Quezon City)
Research Conducted
The Larvicidal Property of Sampaguita Jasminum sambac Leaf Crude Extract on
Mosquito larvae (Aedes aegypti) with Marian H. Boneo and Samantha Ally V. Bismonte

You might also like