Antibacterial activity of hydrolyzed virgin coconut oil

Abstract

Objective:The aim of this study was to examine the influence of the partial hydrolysis of virgin coconut oil (VCO) on it's antibacterial activity. Methods:The VCO used in this study was the productof UD SinarNias. Hydrolysis was carried out by enzyme and sodium hydroxide. Enzymatic hydrolysis using lipozyme was conducted in four different incubation time namely, 3 hours, 6 hours, 9 hours and 12 hours. Alkaline hydrolysis preformed with 25%, 50% and 75% NaOH calculated from the saponification valueof coconut oil. Acidified hydrolyzed VCO was extracted with n-hexane. Recovered hydrolyzed products were mixed with water (5 g in water to make 10 ml) to form water in oil emulsion (w/o). Antibacterial activity test was conducted against bacteria Pseudomonasaeruginosa (ATCC 25619), Staphylococcusaureus (ATCC 29737), Staphylococcus epidermidis (ATCC 12228) and Propionibacterium acnes (ATCC 6918) by diffusion agar method using the paper disc of 6 mm in diameter. Antibacterial activity of hydrolyzed VCO was compared with tetracycline and ampicillin. Results: Un-hydrolyzed VCO did not show antibacterial activity but hydrolyzed oil did. The longer the incubation time and the higher the amount of NaOH used in the hydrolysis increased antibacterial activity. VCO hydrolyzed by enzyme was more effective than those hydrolyzed by sodium hydroxide. Hydrolyzed VCO were more effective against Pseudomonas aeruginosa than other bacteria. Conclusions: Un-hydrolyzed VCO did not inhibit bacterial growth, while VCO after hydrolysis was found to have antibacterial activity. Hydrolyzed VCO by enzyme is more active asantibacterial than VCOhydrolyzed by NaOH. Tetracyclin and ampicillin were more active than those of hydrolyzed VCO.

Full text

Research Article
ANTIBACTERIAL ACTIVITY OF HYDROLYZED VIRGIN COCONUT OIL
Faculty of PharmacyUniversity of Sumatra Utara, MedanIndonesia 20155
Email: jansen@usu.ac.id
Received: 24January 2014, Revised and Accepted: 20February 2014
ABSTRACT
Objective:The aim of this study was to examine the influence of the partial hydrolysis of virgin coconut oil (VCO) on it’s antibacterial activity.
Methods:The VCO used in this study was the productof UD SinarNias. Hydrolysis was carried out by enzyme and sodium hydroxide. Enzymatic
hydrolysis using lipozyme was conducted in four different incubation time namely, 3 hours, 6 hours, 9 hours and 12 hours. Alkaline hydrolysis
preformed with 25%, 50% and 75% NaOH calculated from the saponification valueof coconut oil. Acidified hydrolyzed VCO was extracted with n-
hexane. Recovered hydrolyzed products were mixed with water (5 g in water to make 10 ml) to form water in oil emulsion ( w/o). Antibacterial
activity test was conducted against bacteria Pseudomonasaeruginosa (ATCC 25619), Staphylococcusaureus (ATCC 29737), Staphylococcus
epidermidis (ATCC 12228) and Propionibacterium acnes (ATCC 6918) by diffusion agar method using the paper disc of 6 mm in diameter.
Antibacterial activity of hydrolyzed VCO was compared with tetracycline and ampicillin.
Results: Un-hydrolyzed VCO did not show antibacterial activity but hydrolyzed oil did. The longer the incubation time and the higher the amount of
NaOH used in the hydrolysis increased antibacterial activity. VCO hydrolyzed by enzyme was more effective than those hydrolyz ed by sodium
hydroxide. Hydrolyzed VCO were more effective against Pseudomonas aeruginosa than other bacteria.
Conclusions: Un-hydrolyzed VCO did not inhibit bacterial growth, while VCO after hydrolysis was found to have antibacterial activity. Hydrolyzed
VCO by enzyme is more active asantibacterial than VCOhydrolyzed by NaOH. Tetracyclin and ampicillin were more active than those of hydrolyzed
VCO.
Keywords:VCO, MCT, MCFA, lauric acid, monolaurin,partial hydrolysis, antibacterial
INTRODUCTION
Two kinds of oils can be obtained from coconut tree (Cocosnucifera)
they are coconut oil (copra oil) and virgin coconut oil (VCO). Coconut
oil is extracted from copra by heating process, while VCO is from
coconut milk prepared from fresh and mature coconut meat of
coconut fruit and processed at low temperature. Coconut oil and
VCO are different from most of the other common oils which are
usually composed of long chain fatty acids, while coconut oil is
composed of short and medium chain fatty acids, and therefore
classified as medium chain triglyceride (MCT). Coconut oil has been
used in health promotion and also in ailments prevention and
medication [1,2]. The quality of VCO is determined by medium chain
fatty acid (MCFA) content, especially lauric acid which is influenced
by variety and oil extraction process [3].
Antibiotic resistance is a consequence of the evolutionary adaptation
of bacteria due to the indiscriminate use of antibiotics. In addition, a
high cost and adverse effects are generally associated with synthetic
antibiotics. The emergence of antibiotic resistance in
microorganisms becomes a threat among medical community. There
is a continuous need to discover new antimicrobial compounds with
novel mechanisms of action for new infection diseases. Therefore,
researchers are turning their attention to antimicrobial of plant
origin. Antibacterial activity of ethanolic extract of citrus leaves on
Escherichia coli and Pseudomonas aeruginosa was studied and
found to be active [4]. Essential oils of some selected plants was
evaluated for antibacterial activity on methicillin resistant
staphylococcus aureus, and found that essential oils of Clove and
Cinnamon to be more active against tested bacteria [5]. Evaluation of
antimicrobial activity of Pithecellobiumdulce pod pulp was
conducted and found to be potential bactericidal and fungicidal [6].
Potential of medication of coconut oil and coconut products was
discovered by Jon Kabara in the year of 1970s, who found that
coconut oil has antibacterial, antiviral and antifungal activities
exerted by free MCFAs and mainly by their monoglycerides
molecule, especially monolaurin[7,8].
VCO contains high lauric acid content (46-50%) attached to glycerol
backbone to form a triglyceride. In the human gastrointestinal
tract,triglycerides in VCO can be converted into free fatty acids
mainly lauric acid and monolurin which are active as antibacterial,
antiprotozoal, and antiviral components. Moreover, MCFAsare easily
absorbed into cells and then to mitochondria, increase metabolism,
and hence the cells work more efficiently to form new cells and
hence substitute damaged cells faster [3,8,9].
Antimicrobial activity is due to free fatty acids of medium chain and
their monoglycerides. Triglyceride and diglyceride are not effective
as antibacterial. Of the free fatty acids present in coconut oil, lauric
acid (C:12:0) is proven to be more active as antibacterial agent
compared to caprilic acid (C8:0), capric acid (C10:0), and myristic
acid (C14:0). Free fatty acids and their monoglycerides inactivate
bacteria by disrupting plasma membrane of lipid bilayer[7,10].
Antibacterial activity of free fatty acid or its monoglyceride has been
tested separately [7]. Combination or mixture of free fatty acidsand
their monoglycerides generated from coconut oil could be
synergistic in bacterial inactivation. To generate monoglyceride
from VCO can be done by enzymatic hydrolysis which is effective
specifically on sn-1 and sn-3 position. This specific enzyme can be
obtained from pancreas, Thermomyces lanuginose and
Mucormiehei[11]. Hydrolysis can also be done by saponification
reaction with alcoholic sodium or potassium hydroxide solution.
Saponification byNaOH with or above saponification value will
hydrolyze all triglycerides completely in to glycerol and free fatty
acids as soap [12,13]. However, hydrolysis using NaOH lower than
NaOHneeded for total hydrolysis (saponification value) would
partially hydrolyze oil into mixture of free fatty acids and their
diglyceride or monoglyceride derivatives depending on the amount
NaOH used. The aim of this study was to compare the influence of
Vol 7, Suppl 2, 2014 ISSN - 0974-2441
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Asian J Pharm Clin Res, Vol 7, Suppl 2, 2014, 90-94
91
partial hydrolysis of VCO by enzymeand NaOH on their antimicrobial
activity.
MATERIALS AND METHODS
Apparatus used including vortex (Bender,Germany), analytical
balance (Sartorius, Japan), hotplate (Heidelberg, Germany),
autoclave, oven, spectrophotometer (Shimadzu, Japan), incubator,
reflux condenser, water bath, burette, and glass wares. All chemicals
were pro analysis grade product of E. Merck (Germany) including
potassium and sodium hydroxide, n-hexane, methanol, ethanol, tris-
hydroxymethylaminomethane, hydrochloric acid, calcium chloride,
anhydrous sodium sulfate, phenolphthalein (1% in ethanol) and
Lipozyme TL IM.
VCO used in this study was product of UD SinarNias. Culture media
used were Nutrient Agar(NA), Nutrien Broth (NB), and Mueller
Hinton Agar (MHA). Bacteria tested were Pseudomonas aeruginosa
(ATCC 25619), Staphylococcus aureus (ATCC 29737), Staphylococcus
epidermidis (ATCC 12228) and Propionibacterium acnes (ATCC
6918). Paper disc used was of Machereynagel with 6 mm in
diameter. Antibacterial activity of hydrolyzed VCO was compared
with those of tetracycline and ampicillin.
Reagents used were calcium chloride solution of 0.063 M, Tris-HCl
buffer solution with the pH of 8, HCl solution of 0.5 N, KOH of 0.5 N,
NaOHof 0.5 N, 1% phenolphthalein indicator solution. These
solutions prepared according to procedure described in Indonesian
Pharmacopeia [14]. Medium used were Nutrient Agar(NA), Nutrien
Broth (NB), and Mueller Hinton Agar (MHA). Preparation of these
media used as described in Difco Laboratory Manual [15].
Enzymatic Hydrolysis
Fifty (50) g of oil placed in an erlenmeyer of 250 ml to which 50 ml
water, 12.5 ml CaCl2of 0.063 M, 25 ml buffer solution Tris-HCl and
500 mg lipozyme were added. This mixture was stirred with
magnetic stirrer for 10 minutes to homogenize. Then it was allowed
to stand (incubated) for various length of time; 3, 6, 9, and 12 hrs at
temperature of 40 ± 0.5oC, and shaken the mixture for 10 minutes in
every one hour during incubation. After the hydrolysis was
completed, the mixture was transferred into separating funnel,
acidified with dilute HCl, extracted with 50 ml n-hexane resulted in
two separated layers [13,16]. The upper layer (n-hexane fraction)
was separated and called as filtrate I. The bottom layer was
extracted again with 50 ml n-hexane and separated as filtrate II.
These two filtrates were combined to which then 50 mg anhydrous
Na2SO4 added and allowed to stand for 15 minutes. It was then
evaporated on a water bath to dryness. The recovered hydrolyzed oil
was used in the antibacterial experiment after acid value was
determined.
Hydrolysis with Sodium hydroxide
Ten (10) g of oil placed in a 250 ml conical flask and 100 ml
methanolicNaOHof 0.5 N was added in to it. The flask was attached
with reflux condenser and heated. As the ethanol boiled, the flask
occasionally shaken till the fat completely saponified (~3 hours).
Solution allowed to cool and added 1 ml solution of 1%
phenolphthalein indicator, titrated with HClof 0.5 N till the red color
disappeared. Saponification value was calculated as the amount in
mg of NaOH needed for the saponification [12,13].
Partial hydrolysis of oil was performed with the same procedure as
described in saponification procedure but the amount of NaOHused
was lowerthan the amount of NaOHused in the total saponification
value. Fifty (50) g oil was weighed then added methanolicNaOH with
the amount of 25%, 50% and 75% from saponification value, and
hydrolysis procedure conducted as already described for 3 hrs. After
hydrolysis, then the mixture acidified with dilute HCl in order to
convert soap (sodium salt of fatty acids) into free fatty acids.
Acidified mixture was then shaken and extracted with 50 ml n-
hexane resulted in two separated layers. The upper layer (n-hexane
fraction) separated called as fraction I. The bottom layer shaken
with 50 ml n-hexane and allowed to stand for a while then hexane
fraction was taken as fraction II. The two fractions were combined
and dried by adding 50 mg anhydrous Na2SO4, allowed to stand for
15 minutes. Dehydrated hexane fraction was then heated on a water
bath to evaporate hexane, and dried hydrolyzed oil was then used
for acid value determination prior to antimicrobial test.
Acid Value Determination
Acid value determination was carried out for un-hydrolyzed VCO
and hydrolyzed oil. Five gram oil was transferred in to 200 ml
erlenmeyer, added 25 ml neutralized ethanol of 95%, then heated
for ten minutes on a water bath and occasionally shaken. This
solution then titrated with KOH of 0.1 N using phenolphthalein
indicator solution. Acid value of the oil was calculated [12].
Note:
A= the amount of ml KOH for titration
N = normality of KOH solution
W= weight of oil (g)
Antibacterial Activity Test
Bacterial inoculum was prepared by suspending bacterial colony in
Nutrient Broth Media solution and turbidity was measured at 580
nm to have transmittance of 25% (bacterial concentration is
106cfu/ml). Antibacterial activity test of VCO and hydrolyzed
VCOwas conducted and the results compared with tetracyclineand
ampicillin.The volume of 0.1 ml bacterial inoculum was mixed with
15 ml MHA in a petri dish, allowed to stand until the media
solidified. Tested material was prepared as an emulsion by mixing
VCO and hydrolyzed VCO in water at the same amount of sterile
distilled water (5 g oil mixed with water to 10 ml, concentration was
500 mg/ml). Paper disc was then dipped in the emulsion for 15
minutes and then incubated in prepared media at 36 - 37oC for 24
hours. Antibacterial activity was determined by measuring diameter
of transparent area around the paper disc (zone of inhibition).The
concentration of the tetracyclin and ampicillin tested were prepared
in 5 mg/ml, 1 mg/ml and 0.1 mg/ml. The test was conducted in
three replicates [14,17].
RESULTS AND DISCUSSION
Acid value of VCO and hydrolyzed VCO
Partial hydrolysis of VCO resulted in the generation of free fatty
acids in hydrolyzed VCO, which was measured by acid value. Acid
value of VCO and VCO partially hydrolyzed by NaOH and enzyme is
presented in Table 1.
Tabel 1: Acid value of hydrolyzed virgin coconut oil
Hydrolysis
method
Incubation
time and
degree of
saponification
Acid values (n = 3)
(mg KOH/g oil)
Un-hydrolyzed
-
0.74 ± 0.153
Enzymatic
3 hour
72.02 ± 0.517
6 hour
79.05 ± 3.405
9 hour
108.08 ± 0.845
12 hour
150.88 ± 0.818
Alkaline
hydrolysis
The percentage
ofNaOHrelative
to
saponification
value
25 %
68.15 ± 0.483
50 %
133.87 ± 0.796
75 %
199.77 ± 2.575
From Table 1 can be seen that the acid value of VCO increased after
hydrolysis by enzyme and NaOH. The longer the incubation period in
enzymatic hydrolysis and the higher the amount of NaOH used in the
hydrolysis the higher the acid value.Acid value exerted by NaOH75%

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92
was higher than that by enzymatic hydrolysis with incubation for 12
h. Enzymatic hydrolysis of a triglyceride molecule resulted in 2 fatty
acid molecules and 1 molecule of 2-monoglyceride, while partial
hydrolysis by alkaline was difficult to predict [7,13,19].
Zonesof Inhibition by VCO and Partially Hydrolyzed VCO on
Tested Bacteria
Typical zonesof inhibition to evaluate the antibacterial activities by
measuring diameter of paper disc in agar media of different
hydrolyzed products are presented in Fig. 1.
Fig. 1:Antibacterial activities shown by zones of inhibition by
VCO, hydrolyzed VCO compared with tetracyclin and
ampicillin against Pseudomonas aeruginosa
Note: (A) Zone of inhibition by VCO and hydrolyzed VCO by NaOH;
(B) zone of inhibition by VCO and hydrolyzed VCO by enzyme; (C)
zone inhibition by ampicillin; (D) zone of inhibition by tetracycline.
Zones of Inhibition of VCO hydrolyzed by enzyme and alkaline
(NaOH) are presented in Table 2 and Table 3.Bacterial inactivation
by enzymatic hydrolysis for 12 hours and that by alkaline hydrolysis
(75%) were compared with those of tetracycline and ampicillin
(Table 4).
Table 2: Antibacterial activityof VCO hydrolyzed by enzyme
Tested
bacteria
Antibacterial activity of Hydrolyzed VCO by
enzyme at different incubation time shown by
zones of inhibition (mm)
3 hours
6 hours
9 hours
12 hours
P.
aeruginos
a
11.23±0.1
15
11.30±0.1
00
12.60±0.27
8a
13.43±0.20
8a
S. aureus
10.10±0.2
78
10.10±0.3
50
10.55±0.15
0
11.28±0.36
2a
S.
epidermid
is
9.03±0.07
6
9.68±0.16
1
10.65±0.47
7a
10.65±0.32
8a
P.acnes
9.45±0.05
0
9.57±0.15
3
10.13±0.68
1
10.08±0.46
5
Notea)Zonesof inhibition is significantly difference (P<0.05)
compared with hydrolyzed by enzyme for 3 hours of incubation.
Table 3: Antibacterial activityof VCO hydrolyzed by NaOH
Tested
bacteria
Antibacterial activity of hydrolyzed VCO
byNaOHat different percentage relative to total
saponification value shown by zonesof inhibition
(mm)
25%
50%
75%
P.
aeruginosa
9.87±0.881
10.18±1.056
11.35±1.039
S. aureus
9.20±0.409
9.03±0.029
10.00±0.229b
S.
epidermidis
8.78±0.569
9.53±0.161
11.20±0.397b
P.acnes
9.18±0.808
9.83±0.382
10.53±0.161b
Note:b)Zone of inhibition is significantly difference (P<0.05)
compared with hydrolyzed by NaOH at 25% of saponification
value.Negative antibacterial activity indicated by 6 mm in diameter.
Table 4: Bacterial inhibition of hydrolyzed VCO and antibiotic
tetracycline and ampicillin against tested bacteria
Tested
bacteria
Zones of Inhibition (mm)
Hydrolyzed VCO
(500 mg/ml)
Antibiotic
(mg/ml)
Enzymati
c
(12
hours)
Saponificati
on (75%)
Tetracycli
n
(0.1)
Ampicilli
n
(5)
P.
aeruginos
a
13.43±0.2
08
11.35±1.039
15.90±0.3
91
-
S. aureus
11.28±0.3
62
10.00±0.229
9.15±0.26
5
11.45±0.5
22
S.
epidermi
dis
10.65±0.3
28
11.20±0.397
20.95±0.2
29
10.80±0.2
90
P.acnes
10.08±0.4
65
10.53±0.161
14.15±0.3
12
24.25±0.3
60
Note:(-)zone of inhibition is zero (if diameter is 6 mm)
Hydrolysis of VCO, either by enzyme or NaOH induced antibacterial
activity, but enzymatic hydrolysis was more inductive than by
alkaline hydrolysis. Enzymatic hydrolysis resulted in the formation
of a mixture containing free fatty acids, monolaurin, and
triglycerides depending on the incubation time. The composition
ofoil after alkaline hydrolysis (partial hydrolysis) would be
composed of free fatty acids, monoglycerides, diglyceridesand/or
un-hydrolyzed triglycerides depending on the amount of NaOH used.
The most potential antibacterial activity of MCFA exerted by free
fatty acid and monoglycerides which may inactivate bacteriaby
disrupting microbial plasma membraneof lipid bilayer. Of the many
saturated fatty acids, lauric acid (C:12) shown to be the most active
as antibacterial compared to caprilic(C8:0), carpric(C10:0), and
myristicacid (C14:0) [7,10,18].
In this study, VCO did not show to have antibacterial activity on
tested bacteria, because it contained small amount of free fatty acid
and there was no monolaurin present.On the other hand, a study
showed that VCO without hydrolysis was effective on Pseudomonas
aeruginosaandStaphylococcus aureus, using glycerin as solvent
[20].Bacterial growth inhibition by hydrolyzed VCO was found to be
more active against gram negative Pseudomonas aeruginosathan
gram positive Staphylococcus aureus. The inhibition
ofStaphylococcus epidermidis, was found to be higher by VCO
hydrolyzed by alkaline than that by enzyme, but antibacterial
activity was very low against Propionibacterium acnes.
The evaluation of inhibition can be classified into three categories
based on the diameter of zones of inhibition; very active (above 11
mm), medium activity (active) (between 6-11 mm), while non-active
(6 mm).According to this criterion, un-hydrolyzed VCO was not
active as antimicrobial, where as hydrolyzed VCO by enzyme for 12
hours and by alkaline of 75% were very active since the diameter of
zones of inhibition were above 11 mm (13.43 mm) and 11.35 mm
respectively [21]. The antibacterial activity of synthetic

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monolaurinagainst Staphylococcus aureuswas previously conducted
[18] and reported that zone of inhibition was 13 mm (500 mg/ml)
was better than hydrolyzed VCO in this study with inhibition zone
ranged from 10-11 mm (500 mg/ml) on the same species of
bacteria.This difference could be due to lower content of monolaurin
in the partially hydrolyzed VCO in the present study.
Bacterial inhibition was more effective on gram negative than gram
positive bacteria. It is probably due to the components of hydrolyzed
VCO are non-polar molecules, and therefore they easily interact with
cell membrane and disrupting lipid layer present in the outer part of
cell membrane of gram negative bacteria, while the cell membrane
of gram positive bacteria composed of more peptidoglucan layer
compared with that in gram negative bacteria.The peptidoglucan
layer in gram positive bacteria is rigid and resistant to osmotic lysis
[22,23,24].
Pseudomonas aerugiosa is an opportunistic bacteriacausing infection
when the immunity system of the host is getting
weaker.Pseudomonas aeruginosacould survive from host immunity
system because this bacteria has lipidpolysacharide as a
protectingcomponent [25,26]. It is postulated that the mechanism of
how lauric acid and monolaurin may inactivate bacteria is that by
dissolving lipid component present in bacterial cell membrane [27].
Lipidpolysacharide present in Pseudomonas aeruginosamembrane
through which lauric acid and monolaurin may interact and disrupt
bacterial cell membrane.
Propionibacterium acnes is a gram positive bacteria, itcan not be
inhibited by hydrolyzed VCO. This bacteria may cause skin acnes, a
local inflammation on hair follicle resulted from two stages. In the
first stage is that the excessive sebaceous secretion accumulates in
the hair follicle that is previously blocked by ceratine cells (komedo).
On the second stage is the formation of acne, the excessive sebum
converted into fatty acid by lipase enzymereleased by skin normal
flora Propionibacterium acnes, resulting in inflammation on the
follicle. Acne medication can be done by reducing sebum
productionwith retinoic acidor by lifting off komedoand decreasing
fatty acid content or lipid on the skinwith benzoyl peroxide [24,27].
It is still not clear by which mechanism the fatty acids acting as
antimicrobial agent. But the main target is cell membrane of bacteria
and other mechanisms may involve on the membrane. Retarding
growth effect is related to amphiphilic property of fatty acids
enabling them to interact with cell membrane generating
temporarily or permanent pores of various sizes. With the high
concentration, detergent such as free fatty acids being able to
dissolve cell membrane and hence releasing or disrupting larger
portion.Free fatty acids also influence energy production in cell
membrane by disturbing electron transport chain and oxidative
phosphorilation [28].Probable other processes are cell lysis,
impairing enzyme activities, inactivating macromolecular synthesis,
disturbing nutrient absorption or protein DNA denaturation.
Monolaurinmay act as antimicrobial agent by this mechanism
[28,29].
From Table 4 can be seen that antibacterial activity of enzymatic
hydrolysis is greater than that of alkaline hydrolysis agai nst P.
aeruginosa and S. aureus, but similar toward S. epidermis and P.
acnes. Hydrolyzed VCO indicates much lower antibacterial activity
compared with tetracyclin and ampicillin at very low concentration.
Tetracyclin and ampicillin show different activity against tested
bacteria. Tetracycline is most active toward S. epidermis and the
lowest on S. aureus. On the other hand ampicillin is active against P.
aeruginosa and it is most active against P. acnes. It is reported that
monolaurin and lauric acid derived from coconut oil inactivate
pathogenic bacteria but not the beneficial microorganismor
probiotic. In addition, lauric acid and monolaurin do not develop
microbial resistance while the antibiotic would do [30,31].
CONCLUSIONS
Un-hydrolyzedVCO is not active as antimicrobial, but partial
hydrolysis will increase antibacterial activity. The longer incubation
time in enzymatic hydrolysis and the higher the percentage of NaOH
relative to total saponification during alkaline hydrolysis resulted in
the more effective in antimicrobial activity of hydrolyzed
VCO.Hydrolyzed VCO is more effective against Pseudomonas
aeruginosa (gram negative) compared to other tested bacteria.
Hydrolyzed VCO is not as effective as tetracycline and ampicillin.
Ampicillin is not effective againstPseudomonas aureginosa. The
benefit of VCO used orally as antibacterial is that VCO does not cause
any side effectsince it is a common food component which will be
hydrolyzed by lipase in the gastrointestinal tract. Antibacterial
activity of hydrolyzed VCO is necessary evaluated by in vivo
experiment in order to determine the effective dosage of VCO.
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