The Effects of Cranberry Juice on the Urinary Tract Infection Causing

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The Effects of Cranberry Juice on the(take out, so it flows better) Urinary Tract
Infection Causing Bacteria Known as Escherichia coli.
Shirin Moftakhar and Assal Parsa
Department of Biological Sciences
Saddleback College
Mission Viejo CA 92692
Previous clinical research has found that the consumption of cranberry
products can inhibit urinary tract infection by preventing the adhesion of
Escherichia coli to uroepithelial cells. The two main reasons(compounds) theorized
to contribute to the inhibition of UTI are the(take out) fructose and an unknown
polymeric compound found in cranberries. Investigators are interested in testing the
effects of cranberry juice on the urinary tract infection causing bacteria, E. coli.
Two experimental groups were tested,; one was the cranberry juice and the other
fructose solution. Thirty samples of nutrient broth were inoculated with E. coli and
spread on thirty Petri dishes of nutrient agar. They were divided in three groups of
ten with each group containing chads dipped in cranberry juice for one group,
fructose for the other, and deionized water for the last. After they were incubated
for 72 hours at 37°C, the zones of inhibitions were measured. <An> ANOVA( single
factor or what?) yielded a change(?, do u mean a significant difference between
initial amt & final amt of E. coli) and a Bonferroni correction test was ran(run). The
results of the <Bonferroni> post hoc test indicated that cranberry juice and fructose
repectively (SP, respectively) had a significant effect on the inhibition of E. coli
(p=0.0167).
Introduction
According to National Institutes of Health (NIH), the second most common type
of infection affecting women, the elderly, and infants are(is) urinary tract infections
(UTIs) meaning(studies have shown that) one in three will have a UTI at least once in
her(their) lifetime. The presence of greater(more) than 100,000 units/ml of bacteria in the
urine exceeding(exceeds) a(the) threshold value for significance <,and> can result in(lead
to) urinary tract infection (UTI). Infection arises from bacterial growth within the usually
sterile urinary tract (Guay, 2009). There are two types of UTIs: Lower UTI and Upper
UTI. Lower UTIs involve only(only involve) the bladder, whereas upper UTIs involve
both the bladder and the kidneys (pyelonephritis) (Jepson, 2004). Although the standard
treatment for UTI is antibiotic therapy, rising clinical failure rates of trimethoprimsulfamethoxazole due to bacterial resistance has led physicians in some areas of the
country to consider prescribing fluoroquinolones as first-line treatment (Howell, 2007).
Because of these resistance building abilities, Pharmaceutical companies are constantly
working on the development of new antibiotics. In the meantime, alternative therapies for
prevention of UTI should be taken into consideration to slow down the rate of antibiotic
resistance development.
Cranberry juice (Vaccinium macrocarpon) has been used widely(widely used) for
many years to prevent and treat urinary tract infections. There is positive clinical
evidence that the consumption of cranberry juice can decrease the number of
symptomatic UTI’s based on two randomized double-blind studies on women over a 12month period (Avorn <et al.>(,year? 1994) and Kontiokari (,year? 2001)). However,
there is no prior evidence <showing> that cranberry <juice> can <be used to> treat UTI
once an infection is present. Cranberry juice and cranberry juice cocktail have been
known to inhibit the adherence of bacteria such as E. coli to host tissue (Zafriri, 1989).
Another study also suggests that benefits of cranberry were due to its acidity (Liu, 2008).
Cranberries contain two compounds which inhibit adherence – fructose and a polymeric
compound of unknown nature (Jepson, 2004). Although many juices contain fructose,
only cranberries and blueberries contain the <unknown> polymeric compound. Cranberry
juice will create an acidic state by lowering the pH; this acidic environment will kill and
inhibit the growth of bacteria. The purpose of this study is to determine if cranberry
juice<, with its combination of fructose and the unknown polymeric compound,> or
<just> fructose <alone> do(take out, will) inhibit the growth of UTI by testing it on E.
coli growth.
.
Methods and Materials
Nutrient Agar for culturing Escherichia coli was prepared on 4 November 2009 in
the biology lab at Saddleback College, Mission Viejo, CA. 15 ml(mL’s) of the nutrient
agar was plated in 30 Petri dishes using the aseptic technique. On 5 November 2009, 0.25
ml(mL’s) of E. coli was lawn spread onto all 30 dishes. 20 ml of fructose with a 0.60 M
concentration was prepared. 20 ml of Kirkland Signature cranberry juice cocktail and
deionized water were poured into two 100 ml beakers. One hundred and eighty chads
were made from Wattmans filter paper and autoclaved for 2 hours. Two chads dipped in
DI water were placed on each of the first 10 Petri dishes as the control group which
makes n=20. Two chads dipped in a previously prepared fructose solution were placed on
the each of the 10 petri dishes in the second group. On each of the 10 Petri dishes in the
last group, the chads were dipped in cranberry juice cocktail. All 30 Petri dishes were
placed in the incubator for 72 hours at 37°C. On 11 November 2009, the Petri dishes
were inspected and the zone of inhibition for each dish was measured in centimeters. All
data were transferred to Microsoft Excel 2007 where further statistical
manipulations(calculations) were preformed. Since a change(?, significant diff.)was
found when <an> ANOVA( single factor or what?) <Test> was run; a Bonferroni
correction test was done to compare the results within the groups.
Results
The DI water <Petri dishes> had E. coli growth on top of the chads therefore the
zone of inhibition is(was) zero, while the fructose and cranberry juice had no(zero)
growth on the chads with a ring of no(absent of) E. coli around it. Then (There) was a
significant difference between all three groups(p-value’s?). The greatest difference <in
inhibition zones> was between the DI water <with zero cm> and the cranberry juice
<with a mean of 1.265cm>, while the least(smallest) <difference> was between the
fructose<with a mean of 1cm> and cranberry juice <with a mean of 1.265cm>.
Figure 1. The Cranberry Juice had the highest adhesion rate with a mean <value> of
1.265 cm. The Fructose also had some(look’s like a fairly close amt compared to the
cranberry, this is where the error bars will help show that they r actually significantly
diff.) adhesion with a mean of 1 cm. The DI water had an adhesions rate of 0(zero). The
p-value found (for what test?) for the groups was 0.0167. (where are the SEM error bar’s
on the cranberry and Fructose columns?)
Discussion
Based on our results, it can be concluded that cranberry juice does inhibit E. coli
growth thus inhibiting/preventing urinary tract infection (UTI). The mean difference
between the control group and the experimental groups was at least 1 cm. While
cranberry juice and fructose did have signs of inhibition, the chads in the deionized water
were completely covered in E. coli. There was more of a( a greater) difference between
cranberry juice and the DI water then the fructose and the DI water. This suggests that
although cranberry juice <combination> was the main prohibitor( had the greatest
inhibitory effect), the fructose in the cranberry juice( alone) has inhibitory factors as well.
Zafiri et al. (1989) found that the fructose in cranberry juice and cocktails inhibits the
adherence of type 1 fimbriae of E. coli to the urinary tract epithelial cells. He also found
that there are two types of inhibitors in cranberry juice, a nondialyzable and a dialyzable
one. It was brought to his attention that the main inhibitor was the dialyzable one. The
finding that both cranberry juice cocktail and 5% fructose inhibited yeast agglutination by
purified type 1 fimbriae proves that the fimbriae are the target of inhibitory action. The P
fimbriated E.coli, was also inhibited by the cocktail. The reason they were only inhibited
by the cranberry juice, was that the inhibitor was nondialyzable, suggesting its high
molecular weight.
In Ahuja’s study it was seen that the growth of E. coli in cranberry rich agar
inhibited the attachment of the p receptor specific beads to the epithelial tissue. Until the
chemical nature of the inhibitor is discovered, it is not possible to speculate on the
methods by which it binds to P fimbriated E. coli surfaces. Therefore the possibility that
the possibility that(repeat) the nondialyzable constituents may inhibit adherence mediated
by adhesions other than P fimbriae cannot be ignored. As stated in the introduction, it
was suggested that cranberry juice cocktail may primarily act as a preventive agent in
urinary tract infection. So the possibility that the fructose is abrosbed (absorbed) in the
alimentary tract should be considered. Since cranberry juice has fructose levels higher
than the required amount necessary for type 1 fimbriated E. coli inhibition, it is
conceivable that the inhibitory levels of sugar are determined in the colon where most of
the E. coli is present. A study by Guay showed that antibiotic resistant P fimbriated E.
coli lost the ability to adhere to bladder cell receptors in humans who had consumed 240
ml of cranberry juice cocktail. This suggests that consuming cranberry juice on a daily
basis can not only prevent UTI, but also slow the pace of antibiotic resistance
development by reducing the need for antibiotics. This strategy can be very helpful
considering the increasing antibiotic resistance rates due o(to) over-use of antibiotics.
Literature Cited
Ahuja S, Kaack B, Roberts J: Loss of fimbrial adhesion with the addition of Vaccinum
macrocarpon to the growth medium of Pfimbriated Escherichia coli. J Urol
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Avorn, J., Monane, M., Gurwitz, J. H., Glynn, R. J. et al.,
Reduction of bacteriuria and pyuria after ingestion of cranberry juice, JAMA 1994, 271,
751–754.
Guay, David R.P. (2009). Cranberry and Urinary Tract Infections. Drugs, 69 (7). 775807.
Gupta, K., Hooton, T. M., Stamm, W. E., Increasing antimicrobial resistance and the
management of uncomplicated community-acquired urinary tract infections, Ann. Intern.
Med. 2001, 135, 41–50.
Howell, Amy B. (2007). Bioactive compounds in cranberries and their role in prevention
of urinary tract infections. Molecular Nutrition & Food Research, 51. 732-737.
Jepson, RG., Mihaljevic, L., and Craig, J. (2004). Cranberries for preventing urinary
tract infections. The Cochrane Library, 1. 1-19.
Kontiokari, T., Sundqvist, K., Nuutinen, M., Pokka, T. et al., Randomised trial of
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Liu, Yatao, Gallardo-Moreno, Amparo M., Pinzon-Arango, Paola A., Reynolds, Yorke,
Rodriguez, Guadalupe, Camesano, Terri A. (2008). Cranberry changes the
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Review Form
Department of Biological Sciences
Saddleback College, Mission Viejo, CA 92692
Author (s):_Shirin Moftakhar and Assal Parsa _
Title:_The Effects of Cranberry Juice on the Urinary Tract Infection Causing
Bacteria Known as Escherichia coli.
Summary
Summarize the paper succinctly and dispassionately. Do not criticize here, just show that you understood the paper.
The researchers tested to see if there was an inhibitory effect on the growth to E. coli by
introducing chads soaked in 3 different solutions: cranberry cocktail, fructose with a 0.60
M concentration, and Deionized water. They incubated the 30 Petri dishes samples, 10 in
each group for 72 hours, and then measured the zones of inhibition around the different
chads and compared the averages for each group using one of the ANOVA test’s and also
ran a Bonferroni correction test and found there to be a significant difference between the
groups.
General Comments
Generally explain the paper’s strengths and weaknesses and whether they are serious, or important to our
current state of knowledge.
The paper had a lot of minor grammar mistakes and flow hang ups, which most would
have probably been caught if it was read over a few times, but overall it was good has a
good concise results section and a little adjusting to make the results a bit more clear
where the differences were but the mat and methods were very though.
Technical Criticism
Review technical issues, organization and clarity. Provide a table of typographical errors, grammatical
errors, and minor textual problems. It's not the reviewer's job to copy Edit the paper, mark the
manuscript.
This paper was a rough draft
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