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A COMPARISON OF BACTERIAL CONTAMINATION INBrassica oleracea

(CABBAGE) SOLD IN PUBLIC MARKETS AND SUPERMARKETS IN METRO

MANILA

A research submie! " he

Mah a#! C"m$uer U#i

Facu%& "' Pharmac&

U#iersi& "' Sa#" T"mas

I# $aria% 'u%'i%%me# "' he reuireme#s

i# Mah *++

b&

La$ia#, L"is Faih P-

La&"#, Sea# Russe%% P-

Le.as$i, /useri#i DR-

Lim, Ti''a#& A##e C-

Macasae, Se$ha#ie A##e A-

Gr"u$ 0

1C2Me!ica% Tech#"%".&

Oc"ber 3+41


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C5APTER 4

INTRODUCTION

4-4- Bac6.r"u#! "' he Su!&

Food is one of the basic requirements of living organisms, particularly humans, needed in

order to sustain bodily functions. It is any substance, usually of plant or animal origin, consumed

to provide nourishment to the body. They contain essential nutrients, such as proteins,

carbohydrates, fats, vitamins and minerals needed to produce energy, reproduce or stimulate

growth. Thus, food consumption must be regulated in order to ensure that all food is as safe as

possible.

Food safety is a scientific discipline concerned with handling, preparation and storage of

food in ways to prevent foodborne illness. This includes routines that should be followed to

avoid potentially severe health hazards. The tracks within this line of thought are safety between

the industry and the market and the market and the consumer. Food safety considerations in

industry to market includes the food origin, particularly food labeling, food hygiene, food

additives andpesticide residues, as well as policies and guidelines for the management of

government importand exportinspection andcertificationsystems for foods. In considering

market to consumer food safety, the usual thought is that food ought to be safe in the market and

the concern is safe delivery and preparation of the food for the consumer !gan et al, "##$%.

In the &hilippines, most of our food came from the farms in the provinces directly to the

public markets orpalengkesand supermarkets across the country. ' public market orpalengkeis

a physical retail market that sells food directly from farmers to consumers. It is usually

composed of several dozen stalls arranged in rows under a shared roof managed by local
https://en.wikipedia.org/wiki/Healthhttps://en.wikipedia.org/wiki/Food_labelling_regulationshttps://en.wikipedia.org/wiki/Hygienehttps://en.wikipedia.org/wiki/Food_additiveshttps://en.wikipedia.org/wiki/Food_additiveshttps://en.wikipedia.org/wiki/Pesticidehttps://en.wikipedia.org/wiki/Importhttps://en.wikipedia.org/wiki/Exporthttps://en.wikipedia.org/wiki/Certificationhttps://en.wikipedia.org/wiki/Healthhttps://en.wikipedia.org/wiki/Food_labelling_regulationshttps://en.wikipedia.org/wiki/Hygienehttps://en.wikipedia.org/wiki/Food_additiveshttps://en.wikipedia.org/wiki/Food_additiveshttps://en.wikipedia.org/wiki/Pesticidehttps://en.wikipedia.org/wiki/Importhttps://en.wikipedia.org/wiki/Exporthttps://en.wikipedia.org/wiki/Certification


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government units &abico, "##"%. (eanwhile, a supermarket is a large form of a traditional

grocery store offering a wide variety of food and household products organized into aisles. They

are privately)owned and supplied by the distribution centersof theirparent companies, usually in

the largest city in the area *amlett, "##+%. oth of these markets sell meats, beverages, dairy

products, processed foods, fresh produce and vegetables at different prices.

' vegetable is a part of a plant or the entire plant itself that is edible. (ore than any other

foods, they contain essentialvitamins and mineralsthat are vital for good health and disease

prevention. They are rich in fiber that helps control blood glucose levels and anti)oxidants and

phytochemicals that may reduce the risk of coronary heart disease I'-, "##/%. 0ne of the

numerous vegetables beneficial to man is cabbage.

Brassica oleraceaor cabbage is a leafy green cruciferous vegetable known for its dense

leaved heads. They are closely related to broccoli, cauliflower and sprouts. 'vailable in red and

green varieties, cabbage can be cooked, added raw to salads or stir fries or shredded into a slaw.

It is a good source of beta)carotene, vitamin , phytochemicals and fiber. 1arious studies have

showed that cabbages may lower cancer risks, stimulate enzymes to detoxify the body and

reduce oxidative stress. 0xidative stress is the overload of harmful molecules called oxygen)free

radicals, which are generated by the body. -educing these free radicals may reduce the risk of

colon, lung, prostate, breast, and other cancers (agee, "##$%.

abbage has been linked to outbreaks of somefood)borne illnesses, includingListeria

monocytogenesand Clostridium botulinum. The latter toxin has been traced to pre)made,

packaged coleslaw mixes, while the spores were found on whole cabbages that were otherwise

acceptable in appearance.Shigellaspecies are able to survive in shredded cabbage *arris et al,
http://en.wikipedia.org/wiki/Distribution_centrehttp://en.wikipedia.org/wiki/Distribution_centrehttp://en.wikipedia.org/wiki/Parent_companyhttp://www.netdoctor.co.uk/focus/nutrition/facts/vitamins_minerals/advice.htmhttp://www.netdoctor.co.uk/focus/nutrition/facts/vitamins_minerals/advice.htmhttp://en.wikipedia.org/wiki/Food-borne_illnesshttp://en.wikipedia.org/wiki/Listeria_monocytogeneshttp://en.wikipedia.org/wiki/Listeria_monocytogeneshttp://en.wikipedia.org/wiki/Listeria_monocytogeneshttp://en.wikipedia.org/wiki/Clostridium_botulinumhttp://en.wikipedia.org/wiki/Coleslawhttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Shigellahttp://en.wikipedia.org/wiki/Distribution_centrehttp://en.wikipedia.org/wiki/Parent_companyhttp://www.netdoctor.co.uk/focus/nutrition/facts/vitamins_minerals/advice.htmhttp://en.wikipedia.org/wiki/Food-borne_illnesshttp://en.wikipedia.org/wiki/Listeria_monocytogeneshttp://en.wikipedia.org/wiki/Listeria_monocytogeneshttp://en.wikipedia.org/wiki/Clostridium_botulinumhttp://en.wikipedia.org/wiki/Coleslawhttp://en.wikipedia.org/wiki/Shigella


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"##/%. iological risk assessments have concluded that there is the potential for further

outbreaks linked to cabbage, due to contamination at many stages of the growing, harvesting and

packaging processes. ontaminants from water, humans, animals and soil have the potential to

be transferred to cabbage and from there to the end consumer through the markets where they

bought the vegetable 23 F4', "#5"%.

It is for this reason that the researchers wanted to do a comparison of bacterial

contamination of cabbages sold in public markets and supermarkets in order to determine if the

bacteria present in the cabbages are within the appropriate food safety levels for the consumers.

4-3- Saeme# "' he Pr"b%em

This study aims to compare the bacteria present in cabbages sold in public markets and

supermarkets in (etro (anila.

This study also aims to answer the following questions6

1. 7hat are thebacteria found in cabbages8

". 're the bacteria found in cabbages from the public markets higher or lower

than those found in the supermarkets8

4-1- Ob7ecies "' he Su!&

4-1-4- Ge#era% Ob7ecie

) To determine the presence of bacteria in cabbages sold in public markets and

supermarkets in (etro (anila


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when handling vegetables and others food items. Through this research, we can suggest possible

methods that may improve the quality of vegetables in public markets and supermarkets.

4-*- Sc"$e a#! Limiai"#s

This study is limited on the comparison of bacteria present in the cabbages based on the

number of colonies formed on the (aconkey 'gar and (annitol 3alt 'gar.

The cabbages will be bought from six markets only: three from the public markets

3angandaan &ublic (arket in aloocan ity, alintawak &ublic (arket in !43')alintawak,


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Fi.ure 4Theoretical Framework of omparison of acterial ontamination in abbages

Brassica oleracea% 3old in &ublic (arkets and 3upermarkets in (etro (anila

4-;- De'i#ii"# "' Terms

Brassica oleracea 2 a leafy green vegetable known for its dense leaved heads, closely

related to broccoli, cauliflower and sprouts

F""! ) any substance, usually of plant or animal origin, consumed to provide

nourishment to the body

F""! Sa'e&) a scientific discipline concerned with handling, preparation and storage of

food in ways to prevent foodborne illness

Pub%ic Mar6e@ a market owned, operated andAor managed by the government intended

to serve the general public

OUTPUT

Food safety


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Su$ermar6e@ a market distinct from a wet or dry market and larger than a grocery in

which shoppers serve themselves by using baskets or pushcarts in selecting commodities

from shelves or cold display storage and pay their purchase at the exit


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vegetables and ready)to)eat salads are reservoirs of microorganisms, including bacteria, molds,

and yeasts, which can be introduced into the plant environment during cultivation, harvest,

transport, marketing, and even by the consumer. acteria sometimes reach the interior portions

of the plant through natural openings, as stomata and lenticels survive the sanitization process:

hence, may cause illness following consumption of the contaminated produce. Therefore, careful

preparation of vegetables must be done to ensure safety consumption.

1egetables are any kind of plant product. They refer to the fresh edible portion of

herbaceous plant roots, stems, leaves or fruits. 1egetables are mostly annual crops belonging to

the group of plants called horticultural crops which are diverse in nature. 1egetables can be

grouped into fruit and leafy vegetables depending on the nature of their consumable products or

parts.

The common sources of microorganisms that contaminate leafy vegetables include air,

soil, farm pests nematodes%, handlers, irrigation containers used. =eafy vegetables can become

contaminated whilst growing in the field or during harvest, handling, processing, distribution and

use. 'ny microbial contamination present is likely to reflect the environment through which the

product has passed.

'ccording to the study conducted by *abibu and Taura, vegetables, most specially

cabbages, are often contaminated with Staphylococcus, Streptococcus, Pseudomonas, and

Escherichia coli. 'mong the said bacteria, Staphylococcusis most prevalent because it exists in

humans as a normal flora and transmitted as a result of poor hygiene and unsatisfactory

sanitation. 0ccurrence of Escherichia coli is found because of field contamination or use of

untreated water. *abibu and Taura concluded that environment factors play a ma9or role in the

contamination of the vegetable.


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1egetables have been one of the foreseen causes of food)borne illness due to its exposure

to pathogenic bacteria. 'sikong "#55% explained that the moist condition of the vegetables

fostered by the sprinkling of water together with low temperature condition encourages the

growth of microorganisms. Salmonella spp, Shigella spp, Escherichia coli, Yersinia enterolitica,

Listeria monocytogenes, and Staphylococcus aureusare some of the pathogenic microorganisms

that have been isolated from fruits and vegetables as mentioned by euchat. *ausdorf "#5"%

stated that spoilage of food by microorganisms is mostly contributed to pectolytic enzyme

producing bacteria, molds, and yeasts such asPectobacterium andPseudomonas.

In a study conducted by 3oend9o9o, the produce collected from the samples in local

markets generated more bacteria than those sold in grocery stores. ' possible reason could be the

sterilizations used to increase the shelf life of the produce. !ven with the presence of microbes in

theBrassica oleracea,it has been concluded that the produce is still safe for eating. 0ne of the

most frequently used substances is chlorine: however, it can cause carcinogenic reaction

products when it reacts with organic residues.

In a study conducted by =eff "#5/%, the most abundant bacterial families were

!nterobacteriaceae B/#C mean%D, acillaceae E.C%, and 0xalobacteraceae E.#C%. *owever,

some families had high relative abundances on individual produce types. ;early all of the

abundant bacterial families representing G/C of sequences in any produce type% differed in their

relative abundance among produce types. 'mong these families, only " of 5H bacterial families

did not significantly differ in relative abundances across the produce types. !nterobacteriaceae,

for example, was the most abundant family on bean sprouts, spinach, lettuce, tomatoes, peppers,

alfalfa sprouts and strawberries at least "#C% but had substantially lower relative abundances on

apples, peaches, grapes and mushrooms. 's previously mentioned, !nterobacteriaceae is one


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ma9or group responsible for the clustering patterns as those communities with high relative

abundances of !nterobacteriaceae tended to cluster apart from those with lower relative

abundances. 'pples and peaches tended to have greater relative abundances of

(icrobacteriaceae and 3phingomonadaceae than other produce types. >rape surface

communities displayed relatively strong contributions from the families acillaceae and

'cetobacteraceae, and mushrooms, which showed the strongest differences from other produce

types, had large relative abundances of (icrococcaceae, 3phingobacteriaceae, and

&seudomonadaceae. &atterns in community composition differences at the family level were also

reflected by differences in the dominant genera across the produce types. &antoea sp. had a high

relative abundance in most of the produce types that also had a high relative abundance of

!nterobacteriaceae those with "#C reported above%. *owever, other produce types were

generally characterized by dominant genera specific to that produce type.

In a study conducted by rown et al "#5"%, samples of vegetables from markets were

more frequently contaminated than those from supermarkets. This difference was, however, not

significant. =ettuce +HC in supermarkets: 5##C in markets: % and carrots $C in supermarkets:

5##C in markets: % were the most frequently contaminated vegetable, while tomatoes had the

lowest level of contamination ""C in supermarkets: J#C in markets: % with counts of nil to 5.J

K 5#/cfuAg. 0ne supermarket in the eastern region had lettuce as the only sample being

contaminated by &. aeruginosa with a count of /.# K 5#"cfuAg. 7ith the exception of tomatoes

and lettuce, all other samples were contaminated with high levels of &. aeruginosa. oth samples

of mixed vegetable salad were contaminated, with counts of ". K 5#"cfuAg and .# K 5#/cfuAg.


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C5APTER 1

MET5ODOLOG>

1-4- Research Desi.#


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The research design that will be utilized in this study is cross)sectional. The vegetable

that will be used in this study will be obtained from / public markets and / supermarkets in

(etro (anila at the same day. The number of colonies formed from the public markets and

supermarkets will be compared. Identification of the bacteria found in the cabbages will be done

using different biochemical tests.

1-3- Sam$%i#. Tech#iue

The vegetable that will be used for this research is cabbage. The cabbages will be bought

from three public markets and three supermarkets in (etro (anila. 0nly one sample of

vegetable from each market will be used for this research. The proposed time frame for the

experimentation will be one week to a maximum of two weeks.

1-1- Sam$%e C"%%eci"# a#! Baceria% A#a%&sis

3terile re)sealable plastic bags will be used to collect and transport the purchased samples

to the laboratory. ' pair of forceps will be flamed, allowed to cool, used to pick the samples and

will be transferred into sterile containers. 3terile distilled water will be poured into these

containers. 7ashing will be done by shaking and rocking of the containers.

The washings of the cabbages will be inoculated on (annitol 3alt 'gar and (aconkey

agar. The petri plates will be incubated at /$L for "E hours. 'fter "E hours, colonies will be

observed, counted and recorded.

The colonies will be purified by sub)culturing them in fresh nutrient agar plates. 'fter

purification, the isolates will be maintained using nutrient agar slant and will be kept in the

refrigerator at E# for identification.


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The following biochemical tests will be carried out for the characterization and

identification of the organisms6 olony appearance, >ram?s stain, atalase test, Indole test,

(otility test, oagulase test, itrate 2tilization test, 1oges)&roskauer test, and (ethyl red test.

1-8- Daa A#a%&sis

The statistical test that will be used to analyze the data gathered from the experiment will

be the Independent)3ample t test.

C5APTER 8

RESULTS AND DISCUSSION


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The purposes of this study were to identify the presence of bacteria in cabbages sold in

public and supermarkets, to measure the amount of bacteria present in the cabbages and to

compare the bacterial contamination of these cabbages sold from public and supermarkets. This

chapter presents the analyses of the data gathered from the experiment conducted.

The first sub)problem of the study was to determine the bacteria species found in the

cabbages.

Tab%e 8-4 Summar& "' he is"%ae! baceria a#! #umber "' c"%"#ies "# MacC"#6e& a.ar

a#! Ma##i"% Sa% A.ar 'r"m $ub%ic mar6es a#! su$ermar6es

MARKET MacC"#6e& a.ar (MAC) Ma##i"% Sa% A.ar (MSA)

&ublic (arket 5 ;o growth ;o growth

&ublic (arket " Escherichia coli Staphylococcus aureus

&ublic (arket / ;o growth ;o growth

3upermarket 5 !nterobacter spp. Staphylococcus aureus

3upermarket " !nterobacter spp. !nterobacter spp.

3upermarket / !nterobacter spp. ;o growth

Table E.5 shows the summary of the isolated bacteria on (aconkey agar and (annitol

3alt 'gar from public markets and supermarkets. The isolated bacteria were identified using the

different biochemical tests that were conducted for characterization.

;o growth of bacteria was seen on the (' and (3' plates for &ublic (arket 5 and

&ublic (arket /.

For &ublic (arket ", Escherichia coli and Staphylococcus aureus were isolated.

Escherichia coliwas identified primarily on the results of the Indole test, (ethyl red test, 1oges

&roskauer test, itrate 2tilization test and (otility test. The indole test for Escherichia coli

showed the indicative positive red color of the solution after the Movac?s reagent was added

indicating the ability of the bacteria to produce the enzyme tryptophanase. The (ethyl -ed test


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positive for fermentation of glucose via the butylene glycol pathway. Finally, the itrate

2tilization test showed a blue color of the slant indicating that the organism has the ability to

utilize citrate as a carbon source.

!nterobacter was also isolated from (' plates of 3upermarket " and / and the results

of the Indole test, (ethyl -ed test, 1oges)&roskauer test, itrate 2tilization test and the

appearance of the (' plate were the basis for identification of !nterobacter.

The second sub)problem of the study was to determine if there are more bacteria in the

cabbages found in public markets than in supermarkets.

Tab%e 8-3 Summar& "' he c"%"#ies '"rme! "# MAC a#! MSA

MARKET MacC"#6e& a.ar (MAC) c"%"#ies Ma##i"% Sa% A.ar (MSA) c"%"#ies

&ublic (arket 5 # colonies # colonies

&ublic (arket " 5 colony 5J colonies

&ublic (arket / # colony # colonies

3upermarket 5 5+ colonies J colonies

3upermarket " J# colonies colonies3upermarket / "" colonies # colonies

Table E." shows the number of colonies formed in (aconkey 'gar and (annitol 3alt

'gar from the cabbages bought from public markets and supermarkets. In &ublic (arket 5 and /,

no colonies were formed for both (' and (3'. In &ublic (arket ", 5 colony on (' and 5J

colonies on (3' were formed. In 3upermarket 5, 5+ colonies on (' and J colonies on (3'

were formed. In 3upermarket ", J# colonies and colonies were formed on (' and (3'

respectively. =ast, "" colonies were formed on (' and no colonies were formed on (3' in

3upermarket /.


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2sing the statistical test Independent)3ample t test, the degree of bacterial contamination

in the cabbages from public markets and supermarkets were determined.

Tab%e 8-1 Mea#, Sa#!ar! Deiai"# a#! Sa#!ar! Err"r "' each Mea# "' he T"a%

C"%"#ies '"rme! "# MAC a#! MSA '"r Pub%ic Mar6es a#! Su$ermar6es

Group Statistics

Market N Mean Std. Deviation Std. Error Mean

Total Colonies (MAC and

MSA)

Public 3 5.33 9.3! 5.333

Co""ercial 3 3#.## 3.3# $3.%5%

In Table E./, the mean colonies formed on (' and (3' plates for the public markets

are J.// with a standard deviation of H."/+ and a standard error of J.///. 0n the other hand, the

commercial markets have a mean colonies formed of /#.## with a standard deviation of "/./#"

and a standard error of mean of 5/.EJE.

Tab%e 8-8 I#!e$e#!e#2Sam$%es es "' T"a% C"%"#ies '"r "# MAC a#! MSA "'

Cabba.es 'r"m Pub%ic Mar6es a#! Su$ermar6es

Independent Samples Test

&evene's Test

or Eualit* o

+ariances

t,test or Eualit* o Means

- Si. t d Si. (,

tailed)

Mean

Dierence

Std. Error

Dierence

95/

Conidence

0nterval o

t1e

Dierence

&o2er 44er

Total

Colonies

Eual

variances

assu"ed

3.#9 .$5% ,$.#% % .$6% ,%.66 $%.% ,6%.!%! $5.5$5


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(MAC and

MSA)

Eual

variances

not

assu"ed

,$.#% .6$3 .## ,%.66 $%.% ,%.!! 5.%9%

Table E.E shows the Independent)3amples t test of the total colonies formed on (' and

(3' between public markets and supermarkets. ased on the test, the ;ull *ypothesis *o% is

re9ected due to the significant differences in the computed means of the observed colonies in the

two markets. 3ince the actual p)value is equal to #.5JE greater than the N)level of #.#J%, it is

determined that the variances of the two groups are not significantly different and that there is a

homogeneity of variance. The computed value of the independent t)statistic is )5.$#E, with E

degrees of freedom and a p)value of #.5E. ecause the actual p)value of this statistic is greater

than the N)level of #.#J, it can be concluded that the degree of bacterial contamination of

cabbages in public markets is statistically different from that of the cabbages in the

supermarkets. (ore bacteria are found in the cabbages from the supermarkets than the public

markets.

Re'ere#ces?

Brown, . !. et al. "#$1#%. !iversity of &ntimicrobial 'esistance and (ir)lence

!eterminants in se)domonas aer)ginosa &ssociated with Fresh (egetables.

'etrieved on *ct. 1, #$1+ from

http--www.hindawi.com-o)rnals-imb-#$1#-/#0#/1-

=eff, O. 7., Fierer, ;. "#5/%. acterial ommunities 'ssociated with the 3urfaces of

Fresh Fruits and 1egetables. -etreived on 0ctober 5, "#5/ fromhttp6AAwww.plosone.orgAarticleAinfo6doiA5#.5/$5A9ournal.pone.##JH/5#

!gan, (. . et al. "##$%. ' review of food safety and food hygiene training studies in

the commercial sector. Science Direct: ood Control !" #$%%&' !!"%(!!)%. -etrieved on

'ug. /#, "#5/ from http6AAwww.researchgate.netApublicationA"""/HEJJ#
http://www.hindawi.com/journals/ijmb/2012/426241/http://www.plosone.org/article/info:doi/10.1371/journal.pone.0059310http://www.hindawi.com/journals/ijmb/2012/426241/http://www.plosone.org/article/info:doi/10.1371/journal.pone.0059310


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&abico, '. &. "##"%. 4eath of the &alengke.&hilippine enter for Investigative

Oournalism.

*amlett, O. "##+%. -egulating 2M supermarkets6 an oral)history perspective.*istory +

Policy. 2nited Mingdom.

23 F4'. "#5"%.0utbreaks 'ssociated with Fresh and Fresh)ut &roduce. Incidence,

>rowth, and 3urvival of &athogens in Fresh and Fresh)ut &roduce.nalysis andE-aluation o Pre-enti-e Control /easures or the Control and 0eduction1Elimination o/icrobial *a2ards on resh and resh(Cut Produce. 23 Food and 4rug 'dministration.

(agee, !. "##$%. The 3uper 1eggies6 ruciferous 1egetables. -etrieved from

http6AAwww.netdoctor.co.ukAfocusAnutritionAfactsAoxidativePstressAfruitvegetables.htmQixz

z"aF>R7(


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7hitworth, O. "#5/%. 4 unveils pathogens and foods linked to foodborne illness.

-etrieved on Ouly 5/, "#5/ from http6AAwww.foodqualitynews.comA&ublic)

oncernsA4)unveils)pathogens)and)foods)linked)to)foodborne)illness

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