Chapter 1 - 3 to download this document

7/26/2019 Chapter 1 - 3 to download this document

1/44

Rosario Natonal High School

P.Burgos St. Sapa II, Rosario, Cavite

Comparative Study of Cymbopogon citratus(emon !rass" and

Allium sativum(!arlic" as #os$uito Repellent.

%ulay, &r'ay #.

#a$uinano, erome .%ometita, eric .

&ldecoa, #ar) &nthony C.

Herrera, erico B.

Rodil, #ar) *incent

Reyes, #ar) oseph%umaop, &pple S.

Borgonia, %anica

+-


2/44

Acknowledgement

/he researchers 0ant to give their heartfelt and sincere gratitude to those

teachers and parents 0ho gave their comment, suggestions, and criticisms and all

out support to ma)e this study possi1le.

Special than)s to2

#r. Ronelle *illares, our research adviser for so patient in teaching us

regarding to this matters. &lso for giving his criticisms for us to 1e a1le to improve

our 0rite3ups.

#r. ohn Can &ri1al, for letting us to use the Science a1oratory and for

allo0ing us to use different la1oratory apparatus.

#rs. &ida #a$uinano and our parents for giving us suggestions and

comments a1out our study.

#ost especially to our &lmighty !od, 0ho gave us strength, 0isdom,

guidance, and po0er to ma)e this study. He did not left us in times of trou1les that

0e encounter along the 0ay. He is our inspirations in ma)ing this study a

successful one.

i


3/44

&c)no0ledgement i

Chapter 1

I. Bac)ground of the Study -

II. Statement of the Pro1lem 4

III. Hypothesis 5

I*. Significance of the Study

*. Scope and imitations 6

*I. Conceptual 7rame0or) 8

*II. %efinition of /erms 9

Chapter 2

Revie0 of Related iterature (RR" -

Chapter 3

I. #ethodology

II. 7lo0 Chart +:


4/44

Chapter 1

I. Background of the Study

/he num1er of dengue cases in the 0hole country rapidly increase last yearin the area of u;on, *isayas, and #indanao. In #anila and C&&B&Restern *isayas and in some parts in

#indanao the cases rosed up very fast. %epartment of health 0as alarmed

especially Secretary ?nri$ue =na, so they said that early prevention is the 1est

solution. Cleaning the surrounding, disposing stagnant 0ater etc. /he main

pro1lem is the disease dengue. %engue also )no0n as 1rea)1one fever, is mos$uito

1orne tropical disease caused 1y the dengue virus. Symptoms include fever,

headache and muscle and 'oint pains a characteristics s)in rash that is similar to

measles. %engue is caused 1y mos$uito speciesAedis Aegyptie.#os$uitoes came

from the family nematocera flies2 the culicidae (atin 0ord cule@, genitive culicis

meaning Amidges or Aghat". /he 0ord mos$uito (formed 1y mosea and

dimunativeito" is from the Spanish or Portuguese for Alittle fly. Superticially,

mos$uitoes resem1le crane flies (family /ipulidae" and chirinomid flies (family

Chironomidae". In particular the females of many species of mos$uitoes are 1lood3

eating pest and dangerous vectors of disease, 0here as mem1ers of Chironomid

and /ipulidae are not. #any species of mos$uitoes, nor all strains of a given

species transmit the same )inds of disease, nor do they all transmit the disease

under the same circumstances their ha1it differ. 7or e@ample, some species attach

people in houses, and others prefer to attac) people 0al)ing in the forest. In orderto help on decreasing the cases of dengue, the researchers found out that

Cymbopogon citratus (lemon grass" and Allium sativum (garlic" are effective

alternative for many chemical mos$uito repellent such as %??/. emon grass is a


5/44

-


6/44

native her1 from temperate and 0arm regions li)e India and Philippines. emon

grass is a mem1er of a specie of grass that gro0s to as high as one meter 0ith

leaves of one to -. centimeters in 0idth that gro0s from !al) of a1out 4 to 9

centimeter long 0ith 1ul1ous lo0er end. emon grass has citronella and citral used

in repelling in mos$iotoes. Citronella is an essential oil o1tained from the leaves

and stem of different Cymbopogon citratus (lemon grass". /he oil is used

e@tensively as a source of perfumery chemicals such as citronella, citnellol and

generoil. /hese chemicals find e@tensive in soap, candles and incense etc. =n the

other hand, Citral or 4,83dimetry -3+, 6 octadienal or lemonal, is either a pair or a

mi@ture of terperoids 0ith the molecular formula C-H-6=. /he t0o compounds

are dou1le31ond isomers. !arlic has allicin. &llicin is a su1stance that is very

inimical to mos$uitoes thats 0hy it is said to 1e great insect repelling plant. /his

studys purpose is to lessen the cases of vector31orne diseases spreading out in our

country. /his 0ill serve as an alternative from to@ic chemical insects li)e %??/.

+


7/44

II. Statement of the Problem

General Problem

Is Cymbopogon citratus and Allium sativum are effective to repelmos$uitoesD

Specfc Problem

-. %o the compounds of the su1'ects helps in repelling mos$uitoesD

+. >hat is the amount of e@tract needed to repel mos$uitoesD

4. Is there a significant difference in the compound of the su1'ects to the

amount of e@tract needed to repel mos$uitoesD

4


8/44

III. !ypothe""

General Problem

H2 Cymbopogon citratus and Allium sativum are not effective to repel

mos$uitoes.

H-2 Cymbopogon citratus and Allium sativum are effective to repel

mos$uitoes.

Specfc Problem

-. H2 /he compounds of the su1'ect dont help in repelling mos$uitoes.

H-2 /he compounds of the su1'ect help in repelling mos$uitoes.

+. H2 arge amount of e@tract cannot repel mos$uitoes.

H-2 arge amount of e@tract can repel mos$uitoes.

4. H2 /here no significant difference in the compound of the su1'ect to the

amount of e@tract needed to repel mos$uitoes.

H-2 /here a significant difference in the compound of the su1'ect to the

amount of e@tract needed to repel mos$uitoes.

5

I#. Sgnfcance of the Study


9/44

/he 0hole comparative study could help in controlling and decreasing the

no. of mos$uito that 0ere vectors of diseases. &s mos$uito decreased, disease such

as malaria and dengue could also prevent as the result, the num1ers of the 7ilipino

victims 0ho 0ere suffering from these disease that also caused death 0ill lessen.

Cymbopogon citratus(lemon grass" andAllium sativum(garlic" could 1e an

effective mos$uito repellent to decrease dengue disease and could lead to a healthy

environment, community and people.


10/44

#. Scope and $mtaton"

/his comparative study 0as conducted to determine if Cymbopogon citratus

and Allium sativum can repel mos$uito and to also determine 0hich is more

effective.

/he study started on &ugust +-5 and finished on =cto1er +-5. /his study

0as conducted at Rosario National High School a1oratory and #a$uinanos

residence the testing 0ere conducted 1y the researchers.

/he mos$uito larvae and adult mos$uitoes 0ere the only test su1'ect of the

study.

/heres no other su1'ect used as 0ell as the test organism.

/he researchers decided to use Boiling method to e@tract the Cymbopogon

citratus(lemon grass" and crushed and s$uee;ed to e@tractAllium sativum(garlic".

6


11/44

#I. Conceptual %ramework

8

To comparewhich is more

efective as a

mosquito

repellent.

Cymbopogon citratus(emon !rass"

*s.

Allium sativum

(!arlic"

MOSQUITO


12/44

#II. &efnton of 'erm"

#os$uito 3 are a familyof small, midge3li)e flies2 theCulicidae. &lthough a fe0

species are harmless or even useful to humanity, most are considered a nuisance

1ecause they use their salivation to coat the surface of the s)in of living mammals,

including humans, to consume their 1lood, 0hich causes itchy, oftentimes painful

red 1umps to appear.

!arlic 3 Its close relatives include the onion, shallot, lee), chive, and ra))yo. >ith

a history of human use of over 8, years, garlic is native to central &sia, and has

long 1een a staple in the #editerranean region, as 0ell as a fre$uent seasoning in

&sia, &frica, and ?urope.

emon !rass 3 Cymbopogon, commonly )no0n as lemongrass is a genus of a1out

5 species of grasses, (of 0hich the type speciesis Cymbopogon citratus, a natural

and soft tea an@iolyticnative to 0arm temperate and tropical regions of the =ld

>orldand =ceania.

&llicin 3 is an organosulfur compoundo1tained from garlic, a species in thefamily &lliaceae. It 0as first isolated and studied in the la1oratory 1y Chester .

Cavallitoand ohn Hays Bailey in -:55. >hen fresh garlic is chopped or crushed,

the en;yme alliinaseconverts alliininto allicin, 0hich is responsi1le for the aroma

of fresh garlic.

Citronella 3 is one of the essential oilso1tained from the leaves and stems of

different species of Cymbopogon(lemongrass". /he oil is used e@tensively as asource ofperfumerychemicals such as citronellal, citronelloland geraniol.

9


13/44

Citral 3 Citral, or 4,83dimethyl3+,63octadienal or lemonal, is either a pair, or a

mi@ture of terpenoids0ith the molecular formula C-H-6=. /he t0o compounds are

dou1le 1ond isomers. /heE3isomeris )no0n as geranial or citral &.

%engue 3 also )no0n as 1rea)1one fever, is a mos$uito31ornetropical

diseasecaused 1y the dengue virus. Symptoms

include fever, headache, muscleand'oint pains, and a characteristic s)in rashthat

is similar to measles.

Steam %istillation Process 3 is a special type of distillation (a separation process"

for temperature sensitivematerials li)e natural aromatic compounds.

:


14/44

Chapter 2

(e)ew of (elated $terature *(($+

,o"-uto

#os$uitoes are mem1ers of a family of nematocerid files2

the Culicidae(from the atin culex, genitive culicis, meaning EmidgeE or

EgnatE". /he 0ord Emos$uitoE (formed 1y mosca and diminutive ito" is from

the Spanish or Portuguese for Elittle fly E. Superficially, mos$uitoes resem1le crane

flies (family /ipulidae" and chironomid flies (family Chironomidae". In particular,

the females of many species of mos$uitoes are 1lood3eating pests and

dangerous vectors of diseases, 0hereas mem1ers of the similar3loo)ing

Chironomidae and /ipulidae are not. #any species of mos$uitoes are not 1lood

eaters, and many of those that do create a Ehigh to lo0 pressureE in the 1lood to

o1tain it and do not transmit disease. &lso, in the 1loodsuc)ing species, only the

females suc) 1lood. 7urthermore, even among mos$uitoes that do carry important

diseases, neither all species of mos$uitoes, nor all strains of a given speciestransmit the same )inds of diseases, nor do they all transmit the diseases under the

same circumstancesF their ha1its differ. 7or e@ample, some species attac) people in

houses, and others prefer to attac) people 0al)ing in forests. &ccordingly, in

managing pu1lic health, )no0ing 0hich species, even 0hich strains, of mos$uitoes

0ith 0hich one is dealing is important.

=ver 4, species of mos$uitoes have already 1een descri1ed from various

parts of the 0orld. Some mos$uitoes that 1ite humans routinely act as vectors for a

num1er of infectious diseases affecting millions of people per year.


15/44

-

=thers that do not routinely 1ite humans, 1ut are the vectors for animal diseases,may 1ecome disastrous agents for ;oonosis of ne0 diseases 0hen their ha1itats are

distur1ed, for instance 1y sudden deforestation.

#any scientists have suggested that complete eradication of mos$uitoes

0ould not have serious ecological conse$uences.

#os$uitoes prefer stagnant 0ater 0ithin 0hich to lay their eggs. /hey most

commonly infest ponds, marshes, s0amps and other 0etland ha1itats. Ho0ever,

they are capa1le of thriving in a variety of locations and can successfully gro0 in

num1ers even 0hen not in their natural ha1itat. #any species of mos$uitoes use

containers of 0ater as egg3deposit sites.

Hot, humid environments are most amena1le to mos$uito gro0th and survival.

Infestations can occur easily in tropical areas. Some species have also 1een )no0nto inha1it free;ing locations such as the &rctic Circle. #os$uito larvae can 1e

found in various ha1itats. Some larvae are active in transient 0aters such as

flood0ater, ditches and 0oodland pools. /he Anopheles, Culex, Culiseta,

Coquillettidia and Uranotaeniaspecies 1reed in permanent 1odies of 0ater and

can survive in polluted 0ater as 0ell as fresh0ater, acid 0ater and 1rac)ish 0ater

s0amps. =ther mos$uito larvae may 1e present in container 0ater sources such as

puddles upon leaves and stagnant 0ater 0ithin small pools.

#os$uitoes can act as vectors for many disease3

causing viruses and parasites. Infected mos$uitoes carry these organisms from


16/44

person to person 0ithout e@hi1iting symptoms themselves. #os$uito31orne

diseases include2

--


17/44

*iral diseases, such as yello0 fever, dengue fever and chi)ungunya, transmitted

mostly 1yAedes Aegypti. %engue fever is the most common cause of fever in

travelers returning from the Cari11ean, Central &merica, South &merica, and

South Central &sia. /his disease is spread through the 1ites of infected mos$uitoes

and cannot 1e spread person to person.

Severe dengue can 1e fatal, 1ut 0ith good treatment, less than -G of patients die

from dengue.

/he parasitic diseases collectively called malaria, caused 1y various species

ofPlasmodium, carried 1y mos$uitoes of the genusAnopheles

imphatic filariasis (the main cause of elephantiasis" 0hich can 1e spread 1y

a 0ide variety of mos$uito species

>est Nile *irus is a concern in the nited States, 1ut there are no relia1le

statistics on 0orld0ide cases.

?astern e$uine encephalitis virus is a concern in the eastern nited States.

/ularemia, a 1acterial disease caused 1yFrancisella tularensis, is variously

transmitted, including 1y 1iting flies. Culexand Culisetaare vectors of

tularemia, as 0ell as ar1ovirus infections such as >est Nile virus.

Potential transmission of HI* 0as originally a pu1lic health concern, 1ut practical

considerations and detailed studies of epidemiological patterns suggest that any

transmission of the HI* virus 1y mos$uitoes is at 0orst e@tremely unli)ely.


18/44


19/44

-+*arious species of mos$uitoes are

estimated to transmit various types of disease to more than 8 million people

annually in &frica, South &merica, Central &merica, #e@ico, Russia, and much of

&sia, 0ith millions of resultant deaths. &t least t0o million people annually die of

these diseases, and the mor1idity rates are many times higher still.

#ethods used to prevent the spread of disease, or to protect individuals in areas

0here disease is endemic, include2

*ector control aimed at mos$uito control or eradication

%isease prevention, using prophylactic drugs and developing vaccines

Prevention of mos$uito 1ites, 0ith insecticides, nets, and repellent

Garlc

Allium sativum, commonly )no0n as garlic, is a species in the onion genus,

Allium its close relatives include the onion, shallot, lee), chive, and ra))yo. >ith a

history of human use of over 8, years, garlic is native to central &sia, and has

long 1een a staple in the #editerranean region, as 0ell as a fre$uent seasoning in

&sia, &frica, and ?urope. It 0as )no0n to &ncient ?gyptian, and has 1een used for

1oth culinary and medicinal purposes.


20/44


21/44

-4 !arlic is easy to gro0 and can 1e

gro0n year3round in mild climates. >hile se@ual propagation of garlic is indeed

possi1le, nearly all of the garlic in cultivation is propagated ase@ually, 1y planting

individual cloves in the ground. In cold climates, cloves are planted in the autumn,

a1out si@ 0ee)s 1efore the soil free;es, and harvested in late spring. /he cloves

must 1e planted at sufficient depth to prevent free;etha0 0hich causes mold or

0hite rot !arlic plants are usually very hardy, and are not attac)ed 1y many pests

or diseases. !arlic plants are said to repel ra11its and moles. /0o of the

ma'or pathogens that attac) garlic are nematodes and 0hite rot disease, 0hich

remain in the soil indefinitely after the ground has 1ecome infected. !arlic also can

suffer from pin) root, a typically nonfatal disease that stunts the roots and turns

them pin) or red.

!arlic plants can 1e gro0n closely together, leaving enough space for the 1ul1s to

mature, and are easily gro0n in containers of sufficient depth. !arlic does 0ell in

loose, dry, 0ell drained soils in sunny locations, and is hardy throughout S%&

climate ;ones 5J:. >hen selecting garlic for planting, it is important to pic) large

1ul1s from 0hich to separate cloves. arge cloves, along 0ith proper spacing in

the planting 1ed, 0ill also improve 1ul1 si;e. !arlic plants prefer to gro0 in a soil

0ith a high organic material content, 1ut are capa1le of gro0ing in a 0ide range of

soil conditions and pH levels.

/here are different types or su1species of garlic, most nota1ly hardnec)

garlic and softnec) garlic. /he latitude 0here the garlic is gro0n affects the choice

of type as garlic can 1e day3length sensitive. Hardnec) garlic is generally gro0n in

cooler climatesF softnec) garlic is generally gro0n closer to the e$uator.


22/44

-5


23/44

!arlic scapes are removed to focus all the garlicKs energy into 1ul1 gro0th.

/he scapes can 1e eaten ra0 or coo)ed.

!arlic is 0idely used around the 0orld for its pungent flavor as a seasoning

or condiment. /he garlic plantKs 1ul1 is the most commonly used part of the plant.

>ith the e@ception of the single clove types, garlic 1ul1s are normally divided into

numerous fleshy sections called cloves. !arlic cloves are used for consumption

(ra0 or coo)ed" or for medicinal purposes. /hey have a characteristic pungent,

spicy flavor that mello0s and s0eetens considera1ly 0ith coo)ing.

=ther parts of the garlic plant are also edi1le.

/he leaves and flo0ers (1ul1ils" on the head (spathe" are sometimes eaten. /hey

are milder in flavor than the 1ul1s, and are most often consumed 0hile immature

and still tender. Immature garlic is sometimes pulled, rather li)e a scallion, and

sold as Egreen garlicE. >hen green garlic is allo0ed to gro0 past the EscallionE

stage, 1ut not permitted to fully mature, it may produce a garlic EroundE, a 1ul1

li)e a 1oiling onion, 1ut not separated into cloves li)e a mature 1ul1. &dditionally,

the immature flo0er stal)s (scapes" of the hardnec) and elephant types are

sometimes mar)eted for uses similar to asparagus in stir3fries.

Inedi1le or rarely eaten parts of the garlic plant include the Es)inE and root cluster.

/he papery, protective layers of Es)inE over various parts of the plant are generally

discarded during preparation for most culinary uses, though in Lorea immature

0hole heads are sometimes prepared 0ith the tender s)ins intact. /he root cluster

attached to the 1asal plate of the 1ul1 is the only part not typically considered

palata1le in any form.

-


24/44

!arlic is a fundamental component in many or most dishes of various

regions, including eastern &sia, South &sia, Southeast &sia, the #iddle ?ast,

northern &frica, southern ?urope, and parts of South and Central &merica. /he

flavor varies in intensity and aroma 0ith the different coo)ing methods. It is often

paired 0ith onion, tomato, or ginger. /he parchment3li)e s)in is much li)e the s)in

of an onion, and is typically removed 1efore using in ra0 or coo)ed form. &n

alternative is to cut the top off the 1ul1, coat the cloves 1y dri11ling olive oil (or

other oil31ased seasoning" over them, and roast them in an oven. !arlic softens and

can 1e e@tracted from the cloves 1y s$uee;ing the (root" end of the 1ul1, or

individually 1y s$uee;ing one end of the clove. In Lorea, heads of garlic are

fermented at high temperatureF the resulting product, called 1lac) garlic, is s0eet

and syrupy, and is no0 1eing sold in the nited States, nited

Lingdom and &ustralia.

!arlic may 1e applied to different )inds of 1read to create a variety of

classic dishes, such as garlic 1read, garlic toast, 1ruschetta, crostini and canape.

=ils can 1e flavored 0ith garlic cloves. /hese infused oils are used to season all

categories of vegeta1les, meats, 1reads and pasta.

In some cuisines, the young 1ul1s are pic)led for three to si@ 0ee)s in a

mi@ture of sugar, salt, and spices. In ?astern ?urope, the shoots are pic)led and

eaten as an appeti;er. a1a garlic, prepared 1y soa)ing garlic in vinegar, is a type

of pic)led garlic served 0ith dumplings in northern China to cele1rate the Chinese

Ne0 Mear.

&nimal studies, and some early research studies in humans, have suggested

possi1le cardiovascular 1enefits of garlic. #any studies found garlic

supplementation reduced accumulation of cholesterol on the vascular 0alls of

animals and in humans.


25/44

-6


26/44

&nother study had similar results, 0ith garlic supplementation significantly

reducing aortic pla$ue deposits of cholesterol3fed ra11its. Supplementation 0ith

garlic e@tract inhi1ited vascular calcification in human patients 0ith high 1lood

cholesterol. /he )no0n vasodilative effect of garlic is possi1ly caused

1y cata1olism of garlic3derived polysulfides to hydrogen sulfides in red 1lood cells

(RBCs", a reaction that is dependent on reduced thiols in or on the

RBC mem1rane. Hydrogen sulfide is an endogenous cardio protective vascular

cell3signaling molecule.

& +-+ meta3analysis of randomi;ed, dou1le31lind, place1o3controlled trials

loo)ing at the effects of garlic on serum lipid profiles, found garlic 0as superior to

place1o in reducing serum total cholesterol and triglyceride levels. Compared 0ith

the place1o groups, serum total cholesterol and triglyceride levels in the garlic

groups 0as reduced 1y .+9 (:G CI, .5, .--" mmol O (P .-" and

.-4 (:G CI, .+, .6" mmol O (P Q .-", respectively.

& +- dou1le31lind, parallel, randomi;ed, place1o3controlled trial,

involving patients 0hose routine clinical records in general practice

documented treated 1ut uncontrolled hypertension, concluded, E=ur trial suggests

that aged garlic e@tract is superior to place1o in lo0ering systolic 1lood pressure

similarly to current first line medications in patients 0ith treated 1ut uncontrolled

hypertension.E

Allium sativumhas 1een found to reduce platelet aggregation and hyperlipidemia.

In +8, the BBC reportedAllium sativummay have other 1eneficial properties,

such as preventing and fighting the common cold.


27/44

-8


28/44

Ho0ever, in contrast to these earlier claims concerning the cold3preventing

properties of garlic, a +-+ report in the Cochrane %ata1ase of Systematic

Revie0s concludes that Ethere is insufficient clinical trial evidence regarding the

effects of garlic in preventing or treating the common cold. & single trial suggested

that garlic may prevent occurrences of the common cold 1ut more studies are

needed to validate this finding. Claims of effectiveness appear to rely largely on

poor3$uality evidence.E

!arlic 0as used as an antiseptic to prevent gangrene during >orld >ar I and

>orld >ar II. #ore recently, it has 1een found from a clinical trial that a

mouth0ash containing +.G fresh garlic sho0s good antimicro1ial activity,

although the ma'ority of the participants reported an unpleasant taste and halitosis.

!arlic cloves are used as a remedy for infections (especially chest

pro1lems", digestive disorders, and fungal infections such as thrush. !arlic can 1e

used as a disinfectant 1ecause of its 1acteriostatic and 1actericidal properties.

!arlic has 1een found to enhance thiamin a1sorption, and therefore reduces the

li)elihood for developing the thiamin deficiency 1eri1eri.

In -:+5, it 0as found to 1e an effective 0ay to prevent scurvy, 1ecause of its

high vitamin C content.

!arlic has 1een used reasona1ly successfully in &I%S patients to

treat Cryptosporidiumin an uncontrolled study in China. It has also 1een used 1y

at least one &I%S patient to treat to@oplasmosis, another proto;oal disease.

!arlic supplementation has 1een sho0n to 1oost testosterone levels and the

plasma uteini;ing hormone in rats fed a high protein diet.

-9


29/44

Studies suggest that allicin, a compound found in garlic, may prove to 1e

effective in the treatment of #RS&.

>hen crushed, &llium sativum yields allicin, an anti1iotic and antifungal

compound (phytoncide" discovered 1y Chester . Cavallito and colleagues in -:55.

7resh or crushed garlic also affords the sulfur3containing compounds alliin, a'oene,

diallyl polysulfides, vinyldithiins, S3allylcysteine, and en;ymes, B vitamins,

proteins, minerals, saponins, flavonoids, and #aillard reaction products, 0hich are

not sulfur3containing compounds. 7urthermore, a phytoale@in (alli@in" 0as found,

a nonsulfur compound 0ith a 3pyrone s)eleton structure 0ith antio@idant effects,

antimicro1ial effects, antitumor promoting effects, inhi1ition of aflato@in B+ %N&

1inding, and neurotrophic effects. &lli@in sho0ed an antitumor promoting effect in

vivo, inhi1iting s)in tumor formation 1y /P& and %#B& initiated mice. &nalogs

of this compound have e@hi1ited antitumor promoting effects in in vitro

e@perimental conditions. So alli@in andor its analogs may 1e useful compounds

for cancer prevention.

/he composition of the 1ul1s is appro@imately 95.:G 0ater, -4.49G

organic matter, and -.4G inorganic matter, 0hile the leaves are 98.-5G 0ater,

--.+8G organic matter, and -.:G inorganic matter.

/he phytochemicals responsi1le for the sharp flavor of garlic are produced 0hen

the plantKs cells are damaged. >hen a cell is 1ro)en 1y chopping, che0ing, or

crushing, en;ymes stored in cell vacuoles trigger the 1rea)do0n of several sulfur3

containing compounds stored in the cell fluids (cytosol". /he resultant compounds

are responsi1le for the sharp or hot taste and strong smell o garlic.

1


30/44

Some o the compoun!s are unsta"le an! continue to react over

time. #mong the mem"ers o the onion amil$% garlic has "$ ar

the highest concentrations o initial reaction pro!ucts% ma&ing

garlic much more potent than onion% shallot% or lee&s. #lthough

man$ humans en'o$ the taste o garlic% these compoun!s are

"elieve! to have evolve! as a !eensive mechanism% !eterring

animals such as "ir!s% insects% an! worms rom eating the plant.

& large num1er of sulfur compounds contri1ute to the smell and taste of

garlic. &llicin has 1een found to 1e the compound most responsi1le for the EhotE

sensation of ra0 garlic. /his chemical opens thermo3transient receptor

potential channels that are responsi1le for the 1urning sense of heat in foods. /he

process of coo)ing garlic removes allicin, thus mello0ing its spiciness. &llicin,

along 0ith its decomposition products diallyl disulfide and diallyl trisulfide, are

ma'or contri1utors to the characteristic odor of garlic, 0hile other allicin3derived

compounds, such as vinyldithiins and a'oene sho0 1eneficial in vitro 1iological

activity. Because of its strong odor, garlic is sometimes called the Estin)ing roseE.

>hen eaten in $uantity, garlic may 1e strongly evident in the dinerKs s0eat

and garlic 1reath the follo0ing day. /his is 1ecause garlicKs strong3smelling sulfur

compounds are meta1oli;ed, forming allyl methyl sulfide. &llyl methyl

sulfide (S" cannot 1e digested and is passed into the 1lood. It is carried to the

lungs and the s)in, 0here it is e@creted. Since digestion ta)es several hours, and

release of S several hours more, the effect of eating garlic may 1e present for along time.


31/44


32/44

+The well(&nown phenomenon o

)garlic "reath) is allege!l$ alleviate! "$ eating resh parsle$. The

her" is% thereore% inclu!e! in man$ garlic recipes% such

as pistoupersillade% an! the garlic "utter sprea! use! in garlic

"rea!. *owever% since the o!or results mainl$ rom !igestiveprocesses placing compoun!s such as #MS in the "loo!% an! #MS

is then release! through the lungs over the course o man$ hours%

eating parsle$ provi!es onl$ a temporar$ mas&ing. One wa$ o

accelerating the release o #MS rom the "o!$ is the use o

a sauna.

Because of the S in the 1loodstream, it is 1elieved 1y some to act as a

mos$uito repellent, 1ut no clinically reported evidence suggests it is actually

effective.

&1undant sulfur compounds in garlic are also responsi1le for turning garlic

green or 1lue during pic)ling and coo)ing. nder these conditions (i.e.acidity,

heat" the sulfur3containing compound alliinase react 0ith common amino acids to

ma)e pyrroles, clusters of car1on3nitrogen rings. /hese rings can 1e lin)ed

together into polypyrrole molecules. Ring structures a1sor1 particular 0avelengthsof light and thus appear colored. /he t0o3pyrrole molecule loo)s red, the three3

pyrrole molecule loo)s 1lue and the four3pyrrole molecule loo)s green

(li)e chlorophyll, a tetrapyrrole". i)e chlorophyll, the pyrrole pigments are safe to

eat.


33/44


34/44

+-Allcn

&llicin is an organosulfur compoundo1tained from garlic, a species in the

family &lliaceae. It 0as first isolated and studied in the la1oratory 1y Chester .

Cavallitoand ohn Hays Bailey in -:55. >hen fresh garlic is chopped or crushed,

the en;yme alliinaseconverts alliininto allicin, 0hich is responsi1le for the aroma

of fresh garlic. /he allicin generated is very unsta1le and $uic)ly changes into a

series of other sulfur containing compounds such as diallyl disulfide. It

e@hi1its anti1acterial, antifungal, antiviral, andantiproto;oalactivity. &llicin is

garlicKs defense mechanism against attac)s 1y pests.

&llicin is an oily, slightly yello0 li$uid that gives garlic its uni$ue odor. It is

a thioester of sulfenic acid and is also )no0n as allyl thiosulfinate. Its 1iological

activity can 1e attri1uted to 1oth its antio@idant activity and its reaction 0ith thiol

containing proteins.

In the 1iosynthesis of allicin (thio3+3propene3-3sulfinic acid S3allyl ester",

cysteine is first converted into alliin ( S3allyl33cysteine sulfo@ide". /he

en;yme alliinase, 0hich contains pyrido@sal phosphate (PP", cleaves alliin,

generating allysulfenic acid, pyruvate, and ammonium. &t room temperature

allysulfenic acid is unsta1le and highly reactive, 0hich cause t0o molecules of it to

spontaneously com1ine in a dehydration reaction to form allicin.

&llicin is produced in garlic cells 0hen they are damaged, 0hich is 0hy

garlics scent is most potent once it is 1eing cut or coo)ed. It is 1elieved that alliin

and alliinase are )ept in separate compartments of the cells and can only com1ineonce these compartments have 1een ruptured.

++


35/44

$emon Gra""

emon grass (Cym1opogon citratus", a native her1 from temperate and

0arm regions such as India, is 0idely used in &sian coo)ing and is an ingredient in

many /hai and *ietnamese foods. emon grass use in coo)ing has 1ecome popular

in the Cari11ean and in the nited States for its aromatic citrus flavor 0ith a trace

of ginger.

emon grass is a mem1er of a specie of grass that gro0s to as high as -

meter 0ith leaves of - to -. centimeters in 0idth that gro0s from a stal) of a1out

4 to 9 cm long 0ith 1ul1ous lo0er end.

emon grass is a perennial and tufted grass that is commercially cultivated

in Southeast &sian countries such as /hailand, #alaysia and China. emon grass is

also cultivated in nited States specifically in California and 7lorida. Propagation

is 1y dividing the root clumps.

emon grass oil is e@tracted 1y steam distillation. emongrass oil has a

lemony, s0eet smell and is dar) yello0 to am1er and reddish in color, 0ith a

0atery viscosity. It is also )no0n as Kchoomana pooluK and is also referred to as

KIndian *er1enaK or KIndian #elissa oilK. emon grass oil is a valua1le ingredient in

cosmetics, perfumes and as fragrances for soaps and insect repellants.

emongrass is reportedly has a 0ide variety of therapeutic application. >ith

limited research and studies conducted on humans, emon grass effectiveness is

1ased mainly on the results from animal and la1oratory studies as 0ell as its

reputation as a fol) remedy.


36/44

+4


37/44

emongrass is native to &ustralia and tropical &sia. It is 0idely used as

a her1 in &sian cuisine. It has a su1tle citrus flavor and can 1e dried and po0dered,

or used fresh. It is commonly used in teas, soups, and curries. It is also suita1le for

use 0ith poultry, fish, 1eef, and seafood. It is often used as a tea in &frican

countries such as /ogo and the %emocratic Repu1lic of the Congo and atin

&merican countries such as #e@ico. emongrass oil is used as a pesticide and

a preservative. Research sho0s that lemongrass oil

has antifungal properties. %espite its a1ility to repel insects, its oil is commonly

used as a ElureE to attract honey 1ees. Eemongrass 0or)s conveniently as 0ell as

the pheromone created 1y the honey1eeKs Nasonov gland, also )no0n as

attractant pheromones. Because of this, lemongrass oil can 1e used as a lure 0hen

trapping s0arms or attempting to dra0 the attention of hived 1ees.E

Citronella grass (Cymbopogon nardusand Cymbopogon winterianus" gro0

to a1out + m (6.6 ft" and have magenta3colored 1ase stems. /hese species are used

for the production of citronella oil, 0hich is used in soaps, as an insect

repellent (especially mos$uitoes" in insect sprays and candles, and in

aromatherapy, 0hich is famous in Bintan Island, Indonesia, and

the Philippines. /herefore, its origin is assumed to 1e Indonesia. /he principal

chemical constituents of citronella, geraniol and citronellol, are antiseptics, hence

their use in household disinfectants and soaps. Besides oil production, citronella

grass is also used for culinary purposes, as a flavoring.

Citronella is usually planted in home gardens to 0ard off insects such

as 0hitefly adults. Its cultivation ena1les gro0ing some vegeta1les (e.g. tomatoes

and 1roccoli" 0ithout applying pesticides. Intercropping should include physical

1arriers, for citronella roots can ta)e over the field.


38/44

+5emongrass oil, used as a pesticide and

preservative, is put on the ancient palm3leaf manuscripts found in India as a

preservative. It is used at the =riental Research Institute #ysore, the 7rench

Institute of Pondicherry, the &ssociation for the Preservation of the Saint /homas

Christian Heritage in Lerala, and many other manuscript collections in India. /he

oil also in'ects natural fluidity into the 1rittle palm leaves, and

the hydropho1ic nature of the oil )eeps the manuscripts dry so the te@t is not lost to

decay due to humidity.

?ast Indian lemon grass (Cym1opogon fle@uosus", also called Cochin grassor #ala1ar grass (#alayalam2 (inchippullu", is native to Cam1odia, *ietnam,

India, Sri an)a, Burma, and /hailand, 0hile >est Indian lemon grass

(Cym1opogon citratus" is native to maritime Southeast &sia. It is )no0n as serai in

#alaysia and Brunei, serai or sereh in Indonesia, and tanglad in the Philippines.

>hile 1oth can 1e used interchangea1ly, C. citratus is more suita1le for coo)ing. In

India, C. citratus is used 1oth as a medical her1 and in perfumes. C. citratus is

consumed as a tea for an@iety in Bra;ilian fol) medicine, 1ut a study in humans

found no effect. /he tea caused a recurrence of contact dermatitis in one case.

emon grass is also )no0n asgavati chaha in the #arathi

language (gavat grassF chaha tea", and is used as an addition to tea, and in

preparations such as adha, 0hich is a traditional her1al KsoupK used against

coughs, colds, etc. It has medicinal properties and is used e@tensively in &yurvedicmedicine. It is supposed to help 0ith relieving cough and nasal congestion.


39/44


40/44

+Ctronella ol

Citronella oil is one of the essential oils o1tained from the leaves and stems

of different species of Cymbopogon(lemongrass". /he oil is used e@tensively as a

source of perfumery chemicals such as, citronellol and geraniol. /hese chemicals

find e@tensive use in soap, candles and incense, perfumery, cosmetic and

flavouring industries throughout the 0orld.

Citronella oil is also a plant31ased insect repellent, and has 1een registered

for this use in the nited States since -:59. /he nited States ?nvironmental

Protection &gency considers oil of citronella as a 1iopesticide 0ith a non3to@ic

mode of action. Ho0ever, since citronella insect repellant effects 0ere not proven

0ithin the ?, the use of citronella as an insecticide is prohi1ited under the

Biocidal Product %irective +6.

Research also sho0s that citronella oil has strong antifungal properties, is

effective in calming 1ar)ing dogs, and has even 1een used as a successful spray3on

deterrent against pets destroying household items.

Citronella oil is popular as a KnaturalK insect repellent. Its mos$uito repellent

$ualities have 1een verified 1y research, including effectiveness in repellingAedes

Aegypti (dengue fever mos$uito". /o 1e continually effective most citronella

repellent formulas need to 1e reapplied to the s)in every 4J6 minutes.

Research also indicates that citronella oil is an effective repellent for 1ody

louse, head louse and sta1le flies.

/he S ?nvironmental Protection &gency states that citronella oil has little

or no to@icity 0hen used as a topical insect repellent, 0ith no reports of adverse

effects of concern over a 6 year period.


41/44

+6Because some products are applied to

human s)in, ?P& re$uires proper precautionary la1eling to help assure safe use. If

used according to la1el instructions in the S, citronella is not e@pected to pose

health ris)s to people, including children and other sensitive populations. /he

S 7ood T %rug &dministration considers citronella oil as generally recogni;ed as

safe (!R&S".

Canadian regulatory concerns 0ith citronella as an insect repellent are

primarily 1ased on data3gaps in to@icology, not on incidents.

In ?urope, Ceylon type citronella oil is placed on the category 4 list, 0ith some

safety concern regarding methyl eugenol. In the L, ?.. legislation governing

insect repellents came into force in Septem1er +6, 0hich 1anned citronella as an

active ingredient in any insect repellent products. /his applied to 1oth insect

repellent for humans and animals. It can still 1e sold as a perfume, 1ut must not 1e

sold as an insect repellent.


42/44

+8


43/44

Chapter 3

I. ,ethodology


44/44

II. %lowchart

+iltration,-traction

reparation

or ,-traction/athering o thesu"'ects 0emon

grass an! garlic2

#pplication

Documents

Chapter 1 - 3 to download this document