Skip to main content
Erschienen in: Gut Pathogens 1/2014

Open Access 01.06.2014 | Short report

Inhibitory activity of postbiotic produced by strains of Lactobacillus plantarum using reconstituted media supplemented with inulin

verfasst von: Karwan Yassen Kareem, Foo Hooi Ling, Loh Teck Chwen, Ooi May Foong, Samsudin Anjas Asmara

Erschienen in: Gut Pathogens | Ausgabe 1/2014

Abstract

Background

The present study aimed to determine the inhibitory activity of postbiotic produced by L. plantarum using reconstituted media supplemented with different levels of inulin and to select the best combination based on the modified inhibitory activity (MAU/mL) against pathogens.

Methods

Postbiotics were produced by 6 strains of L. plantarum (RG11, RG14, RI11, UL4, TL1 and RS5) using reconstituted media supplemented with different levels of Inulin (0, 0.2, 0.4, 0.6, 0.8, and 1.0) yielding 36 combinations.

Results

The combination of postbiotic and inulin had higher inhibitory activity than postbiotic alone against all indicator organisms except Pediococcus acidilactici, and E. coli. The RI11 + 0.8% Inulin, RG14 + 0.8% Inulin and RG14 + 0% Inulin had significantly (p < 0.05) higher MAU/mL against P. acidilactici than other treatments. The RI11 + 0.8% Inulin and RG14 + 0.4% Inulin had a significantly (p < 0.05) higher MAU/mL against VRE. The MAU/mL against L. monocytogenes was greater in RI11 + 1.0% Inulin, RI11 + 0.6% Inulin and RI11 + 0.8% Inulin. The combinations of RS5 + 1.0% Inulin, RS5 + 0.8% Inulin and RS5 + 0.6% Inulin had greater MAU/mL against S. enterica; whereas in E. coli, the inhibitory activity had higher activity that can only be found in RS5 + 0.8% Inulin.

Conclusion

Combination of postbiotics and inulin which had higher optical density tends to have lower pH which corresponds to increased inhibitory activity against indicator organisms. The results of this study show that postbiotics and inulin supplementation enable to inhibit proliferation of pathogenic bacteria.
Hinweise

Electronic supplementary material

The online version of this article (doi:10.​1186/​1757-4749-6-23) contains supplementary material, which is available to authorized users.
Karwan Yassen Kareem, Loh Teck Chwen contributed equally to this work.

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

FHL and LTC provided probiotic strains and method to produce postbiotic. KYK and MFO performed inhibitory tests. KYK, LTC, FHL, MFO and SAA contributed to the writing of the manuscript. All authors read and approved the final manuscript.

Background

The act of feeding antibiotics to livestock has been practiced for over fifty years[1]. The mode of action of antibiotics is that they alter microbial metabolism thereby suppressing the growth of pathogenic microbes in the gut[2]. However, the use of antibiotics has been criticised for having negative impacts on animal production and health as it could have residual effects on tissues long after withdrawal. Furthermore, microbial resistance[3], genotoxicity and allergies[4] are other problems caused by the use of antibiotics in the animals.
Moreover, bacteria cause such problems as food poisoning and diarrhea. The bacteria considered as the main cause for food poisoning are L. monocytogenes, Campylobacter, Salmonella, and pathogenic E. coli. One of the most popular disease caused by food-borne bacteria worldwide is Salmonella, which is an important pathogen found in food produced by animals. This type of pathogen usually becomes widespread by trade in non-heated food products made from animal meat. The microbial strains which show resistance to antimicrobials, usually, as a result of antimicrobial procedure in animals, cause hazardous problems for public health[5].
Because of these consequences, there is increasing public awareness and pressure to search for alternatives to antibiotics[6, 7]. Prebiotics, probiotics, postbiotics, and medicinal plants are common natural feed additives recently used in poultry industries to promote the immune response and the performance of birds. Postbiotics are substances produced in the final or intermediate stage of metabolic process in Lactic acid bacteria, while prebiotics are defined as indigestible carbohydrates that leave a desired effect on the host by selective growth stimulation or activation of one or more beneficial bacteria in a large part of the gastrointestinal tract[8]. Recently, various findings have reported that postbiotic possesses myriad beneficial probiotic effects on the growth of animals and particularly the gut health when used as additive in animal diet[911]. One of the features of postbiotics is their ability to reduce pH value thereby inhibiting opportunistic pathogens in the feed and gut of animals. In addition, postbiotics display wide inhibitory activity against various species of pathogens such as Listeria monocytogenes, Clostridium perfringens, Salmonella enterica, and Escherichia coli[1215].
Various studies have been conducted to test the individual efficacy of postbiotics and prebiotics separately. However, no study has been conducted using the combination of prebiotics and postbiotics. Since most postbiotics exhibit probiotic effect, there could be a synergy between a prebiotic and a postbiotic. Thus, the present study was conducted to determine the inhibitory activity of postbiotic produced by 6 strains of L. plantarum using reconstituted media supplemented with different levels of inulin (a prebiotic) and to select the best combination based on the modified inhibitory activity against pathogens and an indicator bacterium.

Methods

Reviving culture

Postbiotic producer

RG11, RG14, RI11, UL4, TL1, and RS5 as Lactobacillus plantarum used in this study were previously isolated from Malaysian fermented food[16, 17] and kept at -20°C in MRS broth containing 20% (v/v) glycerol. The stock cultures were revived twice in de-Mann Rogosa Sharpe (MRS) broth and incubated at 30°C for 48 and 24 hrs subsequently at static condition. Plate spreading was then conducted for the revived cultures, followed by 48 hrs of incubation. A single colony was picked and inoculated into 10 mL MRS broth and incubated for 24 hrs, followed by re-sub-culturing into 10 mL MRS broth and again incubating for 24 hrs. The culture was then ready to be used as an inoculum for the fermentation.

Indicator microorganism

In this study, Pediococcus acidilactici 4–46 was chosen as the indicator due to the fact that it is a common food spoilage bacterium in food products for both humans and animals[18]. The preparation of culture was same as listed in the preparation of the postbiotic producer.

Pathogenic bacteria

The reviving steps of Listeria monocytogenes L-MS, Salmonella enterica S-1000, Escherichia coli E-30 and Vancomysin Resistant Enterococci (VRE) are same as the postbiotic producer, except that nutrient media was used for the cultivation of VRE and S. enterica, incubated at 37°C and 30°C, respectively. E. coli was cultivated in LB broth at 37°C while L. monocyotgenes was cultivated at 30°C in Listeria Enrichment media. All the cultivation was performed under the agitation speed of 150 rpm.

Media preparation

In this study, the reconstituted media of L. plantarum RG11, RG14, RI11, UL4, TL1 and RS5 were prepared for the production of postibiotic according to their composition. They were also mixed with different levels of inulin (0.2%, 0.4%, 0.6%, 0.8% and 1.0%), (w/v) before autoclaved at 118°C for 15 min.

Production of postbiotic by L. plantarum strains

1% (v/v) of inoculum was inoculated into the respective reconstituted media supplemented with different levels of inulin, and incubated at static condition at 30°C. The postbiotic was collected after separating the bacterial cell by centrifugation at 10,000 × g for 15 min and used for analysis.

Analysis

Agar well diffusion assay

The inhibitory activity of the produced postbiotics were tested against indicator microorganism, P. acidilactici and pathogenic microorganisms; L. monocytogenes, S. enterica, VRE and E. coli using the Agar Well diffusion method[19]. A two-fold-serial dilution of postbiotic from 20 to 25 was conducted using 0.85% (w/v) NaCl solution. Each diluted postbiotic was inoculated at 20 μL into the corresponding well on pre-punched MRS agar plate for P. acidilactici and 100 μL into the pre-punched nutrient agar plate for L. monocytogenes, S. enterica and LB agar for E. coli while 60 μL inoculated into corresponding well on nutrient agar plate for VRE. The diameter of each well was 5.5 mm. The postbiotics were allowed to diffuse completely for 1 hr at room temperature before overlaid with 3 mL of corresponding soft agar inoculated with 1% (v/v) of P. acidilactici, L. monocytogenes, S. enterica, VRE, and E. coli, respectively. After incubation at 30°C for 24 hrs, the highest dilution factor with the clear zone’s diameter size larger than 0.1 cm of the initial diameter size was recorded. The diameter of the clear zone (mm) was measured and the modified bacteriocin activity was calculated based on the formula as shown below:
Modified bacteriocin activity : The highest dilution factor Volume of postbiotic mL * diameter of zone mm

Optical density and pH determination

Optical density measured the turbidity of a suspension which reflects cell mass or number of a bacterial culture. 1 mL of culture from each treatment group was centrifuged at 10,000 × g for 15 min. The cell pellet was washed once with 0.85% (w/v) and the optical density was determined at 600 nm using spectrophotometer (Novaspec III, Biochrom, Cambridge, UK). The pH of postbiotics was determined using pH meter (Mettle-Toledo., England).

Statistical analysis

The factorial ANOVA was used for data analysis in this study. Data obtained for the modified bacteriocin activity (MAU/mL), inhibitory zone, pH, and optical density were subjected to generalized linear model of SAS. Duncan multiple range test was used to compare the significant difference of means.

Results and discussion

The modified inhibitory activity against indicator and pathogenic organisms of all the 36 combinations of postbiotics and inulin are presented in Table 1. There were differences of inhibitory activity of different postbiotics produced by reconstituted media supplemented with inulin against different indicator organisms. The treatments P3.I5 (RI11 + 0.8% Inulin), P2.I5 (RG14 + 0.8% Inulin), and P2.I1 (RG14 + 0% Inulin) had a significantly (p < 0.05) higher MAU/mL against P. acidilactici than other treatments. Treatments P3.I5 (RI11 + 0.8% Inulin), P2.I3 (RG14 + 0.4% Inulin), and P2.I5 (RG14 + 0.8% Inulin) had a significantly (p < 0.05) higher MAU/mL against VRE. The MAU/mL against L. monocytogenes were greater in P3.I6 (RI11 + 1.0% Inulin), P3.I4 (RI11 + 0.6% Inulin), and P3.I5 (RI11 + 0.8% Inulin). The P6.I6 (RS5 + 1.0% Inulin), P6.I5 (RS5 + 0.8% Inulin), and P6.I4 (RS5 + 0.6% Inulin) had greater MAU/mL against S. enterica. For the E. coli, inhibitory activity was detected within only RS5, where the treatment P6.I5 (RS5 + 0.8% Inulin), P6.I1 (RS5 + 0% Inulin), and P6.I6 (RS5 + 1.0% Inulin) had higher MAU/mL activity.
Table 1
Modified bacteriocin activity (MAU/ml) score rank of 36 combinations of postbiotics produced by using reconstituted media supplemented with different levels of inulin against pathogens
Treatments
P. acidilactici
VRE
L. monocytogenes
S. enterica
E. coli
Score4
 
MAU/mL
Rank3
MAU/mL
Rank
MAU/mL
Rank
MAU/mL
Rank
MAU/mL
Rank
P31.I52
7866.67 ± 133.33a
1
6488.84 ± 88.88a
1
2240.00 ± 0.00bc
3
433.33 ± 3.33g
7
_
6
162
P3.I6
7200.00 ± 0.00bc
4
6044.40 ± 88.88cd
5
2453.33 ± 53.33a
1
433.33 ± 3.33g
7
_
6
157
P2.I5
7866.67 ± 133.33a
1
6399.96 ± 0.00ab
2
1226.66 ± 26.66d
5
193.33 ± 1.66k
12
_
6
154
P2.I1
7866.67 ± 133.33a
1
6399.96 ± 0.00ab
2
1226.66 ± 26.66d
5
186.66 ± 1.66k
13
_
6
153
P3.I1
7066.67 ± 133.33c
5
6222.18 ± 88.88bc
4
2186.66 ± 53.33c
4
380.00 ± 0.00hi
9
_
6
152
P3.I4
7200.00 ± 0.00bc
4
5688.85 ± 88.88f
9
2293.33 ± 53.33b
2
386.66 ± 3.33f
8
_
6
151
P3.I2
6800.00 ± 0.00cde
7
6222.18 ± 88.88bc
4
2186.66 ± 53.33c
4
380.00 ± 0.00hi
9
_
6
150
P2.I6
7466.67 ± 133.33b
2
6399.96 ± 0.00ab
2
1120.00 ± 0.00de
9
193.33 ± 1.66k
12
_
6
149
P2.I3
7333.33 ± 133.33b
3
6488.84 ± 88.88a
1
1146.66 ± 26.6de
8
170.00 ± 0.00l
14
_
6
148
P4.I5
7066.67 ± 133.33c
5
5066.63 ± 0.00d
10
1226.66 ± 26.66g
5
446.66 ± 3.33f
6
_
6
148
P6.I5
6266.67 ± 133.33gh
11
4888.86 ± 88.88gh
12
1200.00 ± 0.00de
6
813.33 ± 6.66b
2
153.33 ± 3.33a
1
148
P6.I6
6400.00 ± 0.00fg
10
4888.86 ± 88.88gh
12
1200.00 ± 0.00de
6
906.66 ± 6.66a
1
146.66 ± 3.33abc
3
148
P2.I4
7466.67 ± 133.33b
2
6222.18 ± 88.88bc
4
1173.33 ± 26.6de
7
170.00 ± 0.00l
14
_
6
147
P3.I3
6666.67 ± 133.3def
8
6044.40 ± 88.88cd
5
2186.66 ± 53.33c
4
373.33 ± 3.33i
10
_
6
147
P2.I2
7200.00 ± 0.00bc
4
6399.96 ± 0.00ab
2
1120.00 ± 0.00e
9
170.00 ± 0.00l
14
_
6
145
P6.I4
6266.67 ± 133.33gh
4
5066.64 ± 0.00hi
10
1200.00 ± 0.00de
6
786.66 ± 6.66c
3
136.66 ± 3.33c
5
145
P4.I6
6666.67 ± 133.3def
8
4977.75 ± 88.88gh
11
1200.00 ± 0.00de
6
446.66 ± 3.33f
6
_
6
143
P6.I2
6400.00 ± 0.00fg
10
4799.97 ± 0.00hi
13
1200.00 ± 0.00de
6
733.33 ± 6.6d
4
140 ± 0.00bc
4
143
P6.I1
6400.00 ± 0.00fgh
10
4622.19 ± 88.88de
15
1200.00 ± 0.00de
6
746.66 ± 6.66e
5
150 ± 0.00ab
2
142
P4.I1
6933.33 ± 133.33cd
6
4977.75 ± 88.88gh
11
1200.00 ± 0.00de
6
373.33 ± 3.33i
10
_
6
141
P4.I2
6933.33 ± 133.33cd
6
4888.85 ± 88.88gh
12
1200.00 ± 0.00de
6
373.33 ± 3.33i
10
_
6
140
P6.I3
6133.33 ± 133.33gh
12
4711.08 ± 88.88i
14
1200.00 ± 0.00de
6
786.66 ± 6.66c
3
136.66 ± 3.33c
5
140
P1.I1
6666.67 ± 133.3def
8
6399.96 ± 0.0ab
2
693.33 ± 13.33f
10
120.00 ± 0.00m
15
_
6
139
P4.I4
6666.67 ± 133.3def
8
4799.97 ± 0.00c
13
1200.00 ± 0.00de
6
380.00 ± 0.00hi
9
_
6
138
P1.I2
6666.67 ± 266.6def
8
6399.96 ± 0.00ab
2
693.33 ± 13.33f
10
110.00 ± 0.00mno
17
_
6
137
P1.I6
6400.00 ± 0.00fg
10
6399.96 ± 0.00ab
2
693.33 ± 13.33f
10
108.00 ± 1.66mno
18
_
6
134
P4.I3
6533.33 ± 133.3efg
9
4977.75 ± 88.88gh
11
1120.00 ± 0.00e
9
360.00 ± 0.00j
11
_
6
134
P1.I5
6533.33 ± 133.3efg
9
6222.18 ± 88.88bc
4
693.33 ± 13.33f
10
105.00 ± 0.00no
19
_
6
132
P5.I1
6666.67 ± 133.3def
8
6222.18 ± 88.88bc
4
586.66 ± 13.33gh
14
110.00 ± 0.00mno
17
_
6
131
P1.I3
6000.00 ± 0.00h
13
6399.96 ± 0.00ab
2
666.66 ± 13.33fg
11
108.00 ± 1.66mno
18
_
6
130
P5.I3
6000.00 ± 0.00h
13
6311.07 ± 88.88abc
3
600.00 ± 0.00gh
13
120.00 ± 0.00m
15
_
6
130
P5.I4
6000.00 ± 0.00h
13
6311.07 ± 88.88abc
3
586.66 ± 13.33gh
14
116.66 ± 1.66mn
16
_
6
128
P5.I2
6666.67 ± 133.3def
8
6222.18 ± 88.88bc
4
586.66 ± 13.33gh
14
100.00 ± 0.00°
22
_
6
126
P1.I4
6266.67 ± 133.3fgh
11
5955.51 ± 88.88de
6
640.00 ± 0.00fgh
12
103.00 ± 1.66°
20
_
6
125
P5.I6
6000.00 ± 0.00h
13
5866.63 ± 0.00def
7
600.00 ± 0.00gh
13
101.66 ± 1.66°
21
_
6
120
P5.I5
6000.00 ± 0.00h
13
5777.74 ± 88.88ef
8
573.33 ± 13.33h
15
103.33 ± 1.66°
20
_
6
118
a-oMeans (mean of modified bacteriocin activity ± SEM) in the same column with common superscripts are non-significantly different. 1P1-P6 = different postbiotics (RG11, RG14, RI11, UL4, TL1 and RS5), which were numbered 1, 2, 3, 4, 5, 6. 2I1-I6 = Inulin levels (0, 0.2, 0.4, 0.6, 0.8 and 1%). 3Rank of modified bacteriocin activity against single indicator strain, 4Score is the sum of single indicator score as a subtraction of 36 and rank number (score = 36-rank). The treatment with higher score has stronger inhibitory activity against 5 above-mentioned indicator strains. It was arranged in descending order in the column.
The postbiotics produced by the 6 strains of L. plantarum used in this study exhibited broad antimicrobial activity and had the capacity to inhibit both gram positive and gram negative pathogens. This observation corroborates the findings of Sifour et al.[20], who reported that bacteriocin produced by L. plantarum F12 isolated from olive oil had broad inhibitory spectrum against L. monocytogenese. Similarly, Liasi et al.[13] observed that the antimicrobial agent produced by L. plantarum inhibited the growth of a range of gram-positive and gram-negative microorganisms such as L. monocytogenes, E. coli, Staphylococcus aureus and Salmonella enterica. The inhibitory effect, exhibited by the postbiotics and inulin combinations which were observed by the formation of clear and distinct zones around the wells, may be due to the presence of several antimicrobial compounds such as bacteriocins or organic acids[21]. Bacteriocin can be defined as proteineous compounds produced by bacteria, which exhibit bacteriostatic or bactericidal properties[14, 22]. Bacteriocin from L. plantarum is a natural antimicrobial compound capable of inhibiting the growth of pathogens at molecular and cellular levels[23]. The protective effects of bacteriocin as food biopreservative and gut health have been demonstrated[24].
Organic acids act as an acidifying agent, reducing the pH of surrounding and survivability of non-acid-tolerant pathogens. During the production of postbiotic by L. plantarum strains, acetic and lactic acids are produced to promote the growth of producer cells[14, 16]. High concentrations of organic acids and low pH can prevent the proliferation of food-borne pathogens and spoilage organisms[25, 26]. In addition, the enzymatic activity of pathogens could be impaired by organic acids thus forcing the bacterial cell to utilize the remaining energy to oust excess proton H leading to the death of the bacteria[27]. Similarly, based on the mode of action of inulin, a prebiotic has been established. Dunkley et al.[28] and Rehman et al.[29] reported that the indirect antimicrobial effect of prebiotics could be due to production of fermentation products such as bacteriocin and short chain fatty acids capable of reducing pathogens by pH reduction. The production of short chain fatty acids (SCFAs) and bacteriocin capable of reducing pH has been reported as an indirect mechanism by which prebiotics such as inulin exert their antimicrobial influence[28]. According to Remesy et al.[30], fermentation of inulin and FOS leads to a considerable production of organic acids. It is also able to increase acidification of gut contents. Furthermore, prebiotics act as fermentation elements for particular members of the microbiota enhancing their numbers as well as the postbiotic of fermentation[31].
The inhibitory zone of postbiotic combinations against P. acidilactici and VRE is shown in Figure 1. The highest inhibitory zone against P. acidilactici was 9.83 mm in RG14 (0), RG14 (0.8), RG14 (1.0), and RI1 (0.8), whereas the highest inhibitory zone against VRE was 12.16 mm in RG14 (0.4) and RI11 (0.8).
The inhibitory zone of postbiotic combinations against L. monocytogenes, S. enterica, and E. coli is shown in Figure 2. The highest inhibitory zone against L. monocytogenes was 8.66 mm in RG11 (0), RG11 (0.2), RG11 (0.8), and RG11 (1.0), whereas the highest inhibitory zone against S. enterica was 22.66 mm in RS5 (1.0). On the other hand, in E. coli, the inhibitory activity was detected just in RS5 in which the inhibitory zone of the combination RS5 (0.8) was 7.66 mm.
The optical density (OD600) and pH of various combinations of L. plantarum and inulin are shown in Table 2. There are significant differences (p < 0.05) in OD600 between different combinations of postbiotics and inulin. The mean optical density ranges from 1.92 to 2.28. The highest optical density observed in P6.I5 (RS5 + 0.8% Inulin). In contrast, the lowest OD was observed in P5.I6 (TL1 + 1.0% Inulin). As reported by Thu et al.[32], the differences in OD could be due to variation in the physiological and biochemical properties among different strains of L. plantarum. Choe et al.[1] also reported different strains of L. plantarum tend to grow and produce various levels of metabolite which may affect the value of the OD in similar condition. However, it was observed that combinations having higher OD tend to have lower pH. It was also observed that the combinations with low pH have high inhibitory activities against different indicator organisms. This observation was in line with the report of Fooks and Gibson[33] which suggests that low pH could be the probable mechanism of inhibitory action of the metabolites.
Table 2
Optical density of different L. plantarum strains and pH of different postbiotic produced by using reconstituted media supplemented with different levels of inulin
Treatments
OD
pH
P11.I12
2.06 ± 0.03e
4.05 ± 0.008g
P1.I2
2.02 ± 0.03f
4.12 ± 0.003e
P1.I3
1.99 ± 0.00fg
4.15 ± 0.008d
P1.I4
1.98 ± 0.003g
4.15 ± 0.003d
P1.I5
1.98 ± 0.003g
4.15 ± 0.003d
P1.I6
1.98 ± 0.003de
4.15 ± 0.005g
P2.I1
2.00 ± 0.00f
4.04 ± 0.003e
P2.I2
2.00 ± 0.003fg
4.06 ± 0.003fg
P2.I3
1.99 ± 0.003fg
4.06 ± 0.006g
P2.I4
1.99 ± 0.003g
4.07 ± 0.003f
P2.I5
2.0 ± 0.003fg
4.08 ± 0.00f
P2.I6
2.0 ± 0.003de
4.07 ± 0.003g
P3.I1
2.16 ± 0.006d
3.94 ± 0.01h
P3.I2
2.16 ± 0.003d
3.91 ± 0.006i
P3.I3
2.23 ± 0.005bc
3.91 ± 0.00i
P3.I4
2.23 ± 0.003bc
3.90 ± 0.003i
P3.I5
2.24 ± 0.003ab
3.87 ± 0.003kl
P3.I6
2.24 ± 0.00ab
3.87 ± 0.003k
P4.I1
2.20 ± 0.003cd
3.88 ± 0.003k
P4.I2
2.18 ± 0.006d
3.87 ± 0.005k
P4.I3
2.19 ± 0.006cd
3.84 ± 0.003m
P4.I4
2.20 ± 0.006cd
3.83 ± 0.00m
P4.I5
2.24 ± 0.003b
3.80 ± 0.0035n
P4.I6
2.20 ± 0.003cd
3.85 ± 0.00l
P5.I1
1.97 ± 0.003gh
4.34 ± 0.00c
P5.I2
1.94 ± 0.005h
4.37 ± 0.006b
P5.I3
1.94 ± 0.008hi
4.37 ± 0.003ab
P5.I4
1.94 ± 0.003hi
4.38 ± 0.010ab
P5.I5
1.93 ± 0.003hi
4.38 ± 0.01a
P5.I6
1.92 ± 0.003i
4.38 ± 0.005ab
P6.I1
2.25 ± 0.005ab
3.90 ± 0.003ij
P6.I2
2.26 ± 0.005ab
3.88 ± 0.005jk
P6.I3
2.26 ± 0.005ab
3.88 ± 0.003k
P6.I4
2.27 ± 0.005ab
3.87 ± 0.00k
P6.I5
2.28 ± 0.003a
3.85 ± 0.003kl
P6.I6
2.27 ± 0.003ab
3.85 ± 0.003lm
a-nMeans (mean of OD and pH ± SEM) in the same column with common superscripts are non-significantly different. 1P1-P6 = different postbiotics (RG11, RG14, RI11, UL4, TL1 and RS5), which were numbered 1, 2, 3, 4, 5, 6. 2I1-I6 = Inulin levels (0, 0.2, 0.4, 0.6, 0.8 and 1%).

Conclusion

It was evident in this study that postbiotic produced by Lactobacillus plantarum RG11, RG14, RI11, UL4, TL1, and RS5 using reconstituted media supplemented with different levels of inulin have the ability to inhibit various pathogens. Also, the combinations have a stronger inhibitory activity than the postbiotic alone due to the synergistic effect of postbiotic and inulin. The increase in optical density of the combinations contributed to a lower pH. Among the 36 treatments, P3.I5 (RI11 + 0.8% Inulin), P3.I6 (RI11 + 1.0% Inulin), and P2.I5 (RG14 + 0.8% Inulin) showed a higher level of modified bacteriocin activity. The results of this study show that postbiotics and inulin supplementation enable to inhibit proliferation of pathogenic bacteria.

Acknowledgements

This project was supported by Long-Term Research Grant Scheme (LRGS) from Ministry of Education Malaysia.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made.
The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.
The Creative Commons Public Domain Dedication waiver (https://​creativecommons.​org/​publicdomain/​zero/​1.​0/​) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Competing interests

The authors declare that they have no competing interests.

Authors’ contributions

FHL and LTC provided probiotic strains and method to produce postbiotic. KYK and MFO performed inhibitory tests. KYK, LTC, FHL, MFO and SAA contributed to the writing of the manuscript. All authors read and approved the final manuscript.
Anhänge

Authors’ original submitted files for images

Below are the links to the authors’ original submitted files for images.
Literatur
1.
Zurück zum Zitat Choe D, Foo H, Loh T, Hair-Bejo M, Awis Q: Inhibitory property of metabolite combinations produced from lactobacillus plantarum strains. Pertanika J Trop Agric Sci. 2013, 36: 79-88. Choe D, Foo H, Loh T, Hair-Bejo M, Awis Q: Inhibitory property of metabolite combinations produced from lactobacillus plantarum strains. Pertanika J Trop Agric Sci. 2013, 36: 79-88.
2.
Zurück zum Zitat Gadd J: Life Without Antibiotic Digestive Enhancers. Biotechnology in the Feed Industry. 1997, Nicholasville, Kentucky, USA: Proceedings Alltechs 13th Annual Symposium, 277-291. Gadd J: Life Without Antibiotic Digestive Enhancers. Biotechnology in the Feed Industry. 1997, Nicholasville, Kentucky, USA: Proceedings Alltechs 13th Annual Symposium, 277-291.
3.
Zurück zum Zitat Shazali N, Foo HL, Loh TC, Choe DW, Abdul Rahim R: Prevalence of antibiotic resistance in lactic acid bacteria isolated from the faeces of broiler chicken in Malaysia. Gut Pathogens. 2014, 6 (1): doi:10.1186/1757-4749-6-1. Shazali N, Foo HL, Loh TC, Choe DW, Abdul Rahim R: Prevalence of antibiotic resistance in lactic acid bacteria isolated from the faeces of broiler chicken in Malaysia. Gut Pathogens. 2014, 6 (1): doi:10.1186/1757-4749-6-1.
4.
Zurück zum Zitat Markovicv R: The effect of different growth promoters in broiler nutrition on performance and health status.In Master Thesis. Faculty of Veterinary Medicine. Belgrade, Serbia: University of Belgrade; 2005. Markovicv R: The effect of different growth promoters in broiler nutrition on performance and health status.In Master Thesis. Faculty of Veterinary Medicine. Belgrade, Serbia: University of Belgrade; 2005.
5.
Zurück zum Zitat Forshell L, Wierup M: Salmonella contamination: a significant challenge to the global marketing of animal food products. Rev Sci Tech Off Int Epiz. 2006, 25 (2): 541-554. Forshell L, Wierup M: Salmonella contamination: a significant challenge to the global marketing of animal food products. Rev Sci Tech Off Int Epiz. 2006, 25 (2): 541-554.
6.
Zurück zum Zitat McCartney A: Application of molecular biological methods for studying probiotics and the gut flora. Br J Nutr. 2002, 88: 29-37.CrossRef McCartney A: Application of molecular biological methods for studying probiotics and the gut flora. Br J Nutr. 2002, 88: 29-37.CrossRef
7.
Zurück zum Zitat Williams P, Losa R: The use of essential oils and their compounds in poultry nutrition. World Poult. 2001, 17: 14-15. Williams P, Losa R: The use of essential oils and their compounds in poultry nutrition. World Poult. 2001, 17: 14-15.
8.
Zurück zum Zitat Gibson GR, Roberfroid MB: Dietary modulation of the human colonic microbiota. Introducing the concept of prebiotic. J Nutr. 1995, 125: 1401-1412.PubMed Gibson GR, Roberfroid MB: Dietary modulation of the human colonic microbiota. Introducing the concept of prebiotic. J Nutr. 1995, 125: 1401-1412.PubMed
9.
Zurück zum Zitat Loh TC, Thanh NT, Foo HL, HAIR-BEJO M, Azhar BK: Feeding of different levels of metabolite combinations produced by Lactobacillus plantarum on growth performance, fecal microflora, volatile fatty acids and villi height in broilers. Anim Sci J. 2010, 81: 205-214. 10.1111/j.1740-0929.2009.00701.x.CrossRefPubMed Loh TC, Thanh NT, Foo HL, HAIR-BEJO M, Azhar BK: Feeding of different levels of metabolite combinations produced by Lactobacillus plantarum on growth performance, fecal microflora, volatile fatty acids and villi height in broilers. Anim Sci J. 2010, 81: 205-214. 10.1111/j.1740-0929.2009.00701.x.CrossRefPubMed
10.
Zurück zum Zitat Choe DW, Loh TC, Foo HL, Hair-Bejo M, Awis QS: Egg production, faecal pH and microbial population, small intestine morphology, and plasma and yolk cholesterol in laying hens given liquid metabolites produced by Lactobacillus plantarum strains. Br Poultry Sci. 2012, 53: 106-115. 10.1080/00071668.2012.659653.CrossRef Choe DW, Loh TC, Foo HL, Hair-Bejo M, Awis QS: Egg production, faecal pH and microbial population, small intestine morphology, and plasma and yolk cholesterol in laying hens given liquid metabolites produced by Lactobacillus plantarum strains. Br Poultry Sci. 2012, 53: 106-115. 10.1080/00071668.2012.659653.CrossRef
11.
Zurück zum Zitat Thu TV, Loh TC, Foo HL, Yaakub H, Bejo MH: Effects of liquid metabolite combinations produced by Lactobacillus plantarum on growth performance, faeces characteristics, intestinal morphology and diarrhoea incidence in postweaning piglets. Tropl Anim Health Prod. 2011, 43 (1): 69-75. 10.1007/s11250-010-9655-6.CrossRef Thu TV, Loh TC, Foo HL, Yaakub H, Bejo MH: Effects of liquid metabolite combinations produced by Lactobacillus plantarum on growth performance, faeces characteristics, intestinal morphology and diarrhoea incidence in postweaning piglets. Tropl Anim Health Prod. 2011, 43 (1): 69-75. 10.1007/s11250-010-9655-6.CrossRef
12.
Zurück zum Zitat Gaggìa F, Mattarelli P, Biavati B: Probiotics and prebiotics in animal feeding for safe food production. Int J Food Microbiol. 2010, 2010 (141): S15-S28.CrossRef Gaggìa F, Mattarelli P, Biavati B: Probiotics and prebiotics in animal feeding for safe food production. Int J Food Microbiol. 2010, 2010 (141): S15-S28.CrossRef
13.
Zurück zum Zitat Liasi SA, Azmi T, Hassan MD, Shuhaimi M, Rosfarizan M, Ariff AB: Antimicrobial activity and antibiotic sensitivity of three isolates of lactic acid bacteria from fermented fish product, Budu. Malays J Microbiol. 2009, 5: 33-37. Liasi SA, Azmi T, Hassan MD, Shuhaimi M, Rosfarizan M, Ariff AB: Antimicrobial activity and antibiotic sensitivity of three isolates of lactic acid bacteria from fermented fish product, Budu. Malays J Microbiol. 2009, 5: 33-37.
14.
Zurück zum Zitat Savadogo A, Ouattara AC, Bassole HI, Traore SA: Bacteriocins and lactic acid bacteria-a minireview. Afr J Biotechnol. 2006, 5: 678-683. Savadogo A, Ouattara AC, Bassole HI, Traore SA: Bacteriocins and lactic acid bacteria-a minireview. Afr J Biotechnol. 2006, 5: 678-683.
15.
Zurück zum Zitat Thanh NT, Loh TC, Foo HL, HAIR-BEJO M, Azhar BK: Inhibitory activity of metabolites produced by Lactobacillus plantarum isolated from Malaysian fermented food. Int J Probiotics Prebiotics. 2010, 5: 37-44. Thanh NT, Loh TC, Foo HL, HAIR-BEJO M, Azhar BK: Inhibitory activity of metabolites produced by Lactobacillus plantarum isolated from Malaysian fermented food. Int J Probiotics Prebiotics. 2010, 5: 37-44.
16.
Zurück zum Zitat Foo HL, Loh TC, Law FL, Lim YS, Kuflin CN, Rusul G: Effect of feeding L. plantarum I-UL4 isolated from Malaysian Tempeh on growth performance, fecla flora and lactic acid bacteria and plasma cholesterol concentrations in post weaning rats. J Food Sci Biotechnol. 2003, 12: 403-408. Foo HL, Loh TC, Law FL, Lim YS, Kuflin CN, Rusul G: Effect of feeding L. plantarum I-UL4 isolated from Malaysian Tempeh on growth performance, fecla flora and lactic acid bacteria and plasma cholesterol concentrations in post weaning rats. J Food Sci Biotechnol. 2003, 12: 403-408.
17.
Zurück zum Zitat Moghadam MS, Foo HL, Leow TC, Rahim RA, Loh TC: Novel bacteriocinogenic Lactobacillus plantarum strains and their differentiation by sequence analysis of 16S rDNA, 16S-23S and 23S-5S intergenic spacer regions and randomly amplified polymorphic DNA analysis. Food Technol Biotechnol. 2010, 48 (4): 476-483. Moghadam MS, Foo HL, Leow TC, Rahim RA, Loh TC: Novel bacteriocinogenic Lactobacillus plantarum strains and their differentiation by sequence analysis of 16S rDNA, 16S-23S and 23S-5S intergenic spacer regions and randomly amplified polymorphic DNA analysis. Food Technol Biotechnol. 2010, 48 (4): 476-483.
18.
Zurück zum Zitat Waite JG, Jones JM, Yousef AE: Isolation and identification of spoilage microorganisms using food-based media combined with rDNA sequencing: ranch dressing as a model food. Food Microbiol. 2009, 26: 235-239. 10.1016/j.fm.2009.01.001.CrossRefPubMed Waite JG, Jones JM, Yousef AE: Isolation and identification of spoilage microorganisms using food-based media combined with rDNA sequencing: ranch dressing as a model food. Food Microbiol. 2009, 26: 235-239. 10.1016/j.fm.2009.01.001.CrossRefPubMed
20.
Zurück zum Zitat Sifour M, Tayeb I, Haddar HO, Namous H, Aissaoui S: Production and characterization of bacteriocin of Lactobacillus plantarum F12 with inhibitory activity against Listeria monocytogenes. Online J Sci Technol. 2012, 2: 55-61. Sifour M, Tayeb I, Haddar HO, Namous H, Aissaoui S: Production and characterization of bacteriocin of Lactobacillus plantarum F12 with inhibitory activity against Listeria monocytogenes. Online J Sci Technol. 2012, 2: 55-61.
21.
Zurück zum Zitat Labioui H, Elmoualdi L, El Yachioui M, Ouhssine M: Sélection de souches de bactéries lactiques antibactériennes. Bull Soc Pharm Bordeaux. 2005, 144: 237-250. Labioui H, Elmoualdi L, El Yachioui M, Ouhssine M: Sélection de souches de bactéries lactiques antibactériennes. Bull Soc Pharm Bordeaux. 2005, 144: 237-250.
23.
Zurück zum Zitat Drider D, Fimland G, Héchard Y, McMullen LM, Prévost H: The continuing story of class IIa bacteriocins. Microbiol Mol Biol Rev. 2006, 70: 564-582. 10.1128/MMBR.00016-05.PubMedCentralCrossRefPubMed Drider D, Fimland G, Héchard Y, McMullen LM, Prévost H: The continuing story of class IIa bacteriocins. Microbiol Mol Biol Rev. 2006, 70: 564-582. 10.1128/MMBR.00016-05.PubMedCentralCrossRefPubMed
24.
Zurück zum Zitat Brashears MM, Amezquita A, Jaroni D, Steve L: Lactic acid bacteria and their uses in animal feeding to improve food safety. Adv Food Nutr Res. 2005, 50: 2-32. Brashears MM, Amezquita A, Jaroni D, Steve L: Lactic acid bacteria and their uses in animal feeding to improve food safety. Adv Food Nutr Res. 2005, 50: 2-32.
25.
Zurück zum Zitat Adams M, Hall C: Growth inhibition of food‒borne pathogens by lactic and acetic acids and their mixtures. Int J Food Sci Technol. 1988, 23: 287-292.CrossRef Adams M, Hall C: Growth inhibition of food‒borne pathogens by lactic and acetic acids and their mixtures. Int J Food Sci Technol. 1988, 23: 287-292.CrossRef
26.
Zurück zum Zitat Cintas L, Casaus M, Herranz C, Nes I, Hernández P: Review: bacteriocins of lactic acid bacteria. Food Sci Technol Int. 2001, 7: 281-305. 10.1177/108201301772660538.CrossRef Cintas L, Casaus M, Herranz C, Nes I, Hernández P: Review: bacteriocins of lactic acid bacteria. Food Sci Technol Int. 2001, 7: 281-305. 10.1177/108201301772660538.CrossRef
27.
Zurück zum Zitat Holyoak CD, Stratford M, McMullin Z, Cole MB, Crim-mins K, Brown AJP, Coote P: Activity of the membrane H1-ATPase and optimal glycolyticflux required for rapid adaptation and growth in the presence of weak acid preservative sorbic acid. Appl Environ Microbiol. 1996, 62: 3158-3164.PubMedCentralPubMed Holyoak CD, Stratford M, McMullin Z, Cole MB, Crim-mins K, Brown AJP, Coote P: Activity of the membrane H1-ATPase and optimal glycolyticflux required for rapid adaptation and growth in the presence of weak acid preservative sorbic acid. Appl Environ Microbiol. 1996, 62: 3158-3164.PubMedCentralPubMed
28.
Zurück zum Zitat Dunkleya KD, Callaway TR, Chalovaa VI, McReynolds JL, Hume ME, Dunkley CS, Kubena LF, Nisbet DJ, Ricke SC: Foodborne Salmonella ecology in the avian gastrointestinal tract. Anaerobe. 2009, 15: 26-35. 10.1016/j.anaerobe.2008.05.007.CrossRef Dunkleya KD, Callaway TR, Chalovaa VI, McReynolds JL, Hume ME, Dunkley CS, Kubena LF, Nisbet DJ, Ricke SC: Foodborne Salmonella ecology in the avian gastrointestinal tract. Anaerobe. 2009, 15: 26-35. 10.1016/j.anaerobe.2008.05.007.CrossRef
29.
Zurück zum Zitat Rehman H, Vahjen W, Kohl-Parisini A, Ijaz A, Zentek J: Influence of fermentable carbohydrates on the intestinal bacteria and enteropathogens in broilers. Worlds Poult Sci J. 2009, 65: 75-90. 10.1017/S0043933909000063.CrossRef Rehman H, Vahjen W, Kohl-Parisini A, Ijaz A, Zentek J: Influence of fermentable carbohydrates on the intestinal bacteria and enteropathogens in broilers. Worlds Poult Sci J. 2009, 65: 75-90. 10.1017/S0043933909000063.CrossRef
30.
Zurück zum Zitat Re’me’sy C, Levrat MA, Gamet L: Cecal fermentations in rats fed oligosaccharides (inulin) are modulated by dietary calcium level. Am J Physiol. 1993, 264: G855-G862. Re’me’sy C, Levrat MA, Gamet L: Cecal fermentations in rats fed oligosaccharides (inulin) are modulated by dietary calcium level. Am J Physiol. 1993, 264: G855-G862.
31.
Zurück zum Zitat Yang Y, Iji P, Choct M: Dietary modulation of gut microflora in broiler chickens: a review of the role of six kinds of alternatives to in-feed antibiotics. Worlds Poult Sci J. 2009, 65: 97-114. 10.1017/S0043933909000087.CrossRef Yang Y, Iji P, Choct M: Dietary modulation of gut microflora in broiler chickens: a review of the role of six kinds of alternatives to in-feed antibiotics. Worlds Poult Sci J. 2009, 65: 97-114. 10.1017/S0043933909000087.CrossRef
32.
Zurück zum Zitat Thu TV, Foo HL, Loh TC, Bejo MH: Inhibitory activity and organic acid concentrations of metabolite combinations produced by various strains of Lactobacillus plantarum. Afr J Biotechnol. 2011, 10 (8): 1359-1363. Thu TV, Foo HL, Loh TC, Bejo MH: Inhibitory activity and organic acid concentrations of metabolite combinations produced by various strains of Lactobacillus plantarum. Afr J Biotechnol. 2011, 10 (8): 1359-1363.
33.
Zurück zum Zitat Fooks LJ, Gibson GR: In vitro investigations of the effect of probiotics and prebiotics on selected human intestinal pathogens. FEMS Microbiol Ecol. 2002, 39: 67-75. 10.1111/j.1574-6941.2002.tb00907.x.CrossRefPubMed Fooks LJ, Gibson GR: In vitro investigations of the effect of probiotics and prebiotics on selected human intestinal pathogens. FEMS Microbiol Ecol. 2002, 39: 67-75. 10.1111/j.1574-6941.2002.tb00907.x.CrossRefPubMed
Metadaten
Titel
Inhibitory activity of postbiotic produced by strains of Lactobacillus plantarum using reconstituted media supplemented with inulin
verfasst von
Karwan Yassen Kareem
Foo Hooi Ling
Loh Teck Chwen
Ooi May Foong
Samsudin Anjas Asmara
Publikationsdatum
01.06.2014
Verlag
BioMed Central
Erschienen in
Gut Pathogens / Ausgabe 1/2014
Elektronische ISSN: 1757-4749
DOI
https://doi.org/10.1186/1757-4749-6-23

Weitere Artikel der Ausgabe 1/2014

Gut Pathogens 1/2014 Zur Ausgabe

Leitlinien kompakt für die Innere Medizin

Mit medbee Pocketcards sicher entscheiden.

Seit 2022 gehört die medbee GmbH zum Springer Medizin Verlag

Update Innere Medizin

Bestellen Sie unseren Fach-Newsletter und bleiben Sie gut informiert.