Influence of 2 0-fucosyllactose and galacto-oligosaccharides on the growth
and adhesion of Streptococcus mutans
K. Salli1,2*, E. Söderling2, J. Hirvonen1, U. K. Gürsoy2 and A. C. Ouwehand1
1DuPont Nutrition & Biosciences, Kantvik, Finland
2Faculty of Medicine, Institute of Dentistry, University of Turku, Turku, Finland
(Submitted 31 December 2019 – Final revision received 5 May 2020 – Accepted 27 May 2020 – First published online 5 June 2020)
Abstract
Human milk oligosaccharides, such as 2 0-fucosyllactose (2 0-FL), and galacto-oligosaccharides (GOS), a prebiotic carbohydrate mixture, are
being increasingly added to infant formulas, necessitating the understanding of their impact on the oral microbiota. Here, for the first time,
the effects of 2 0-FL and GOS on the planktonic growth and adhesion characteristics of the caries-associated oral pathogen Streptococcus mutans
were assessed, and the results were compared against the effects of xylitol, lactose and glucose. There were differences in S. mutans growth
between 2 0-FL and GOS. None of the three S. mutans strains grew with 2 0-FL, while they all grew with GOS as well as lactose and glucose.
Xylitol inhibited S. mutans growth. The adhesion of S. mutans CI 2366 to saliva-coated hydroxyapatite was reduced by 2 0-FL and GOS.
Exopolysaccharide-mediated adhesion of S. mutansDSM 20523 to a glass surface was decreasedwith 2 0-FL, GOS and lactose, and the adhesion
of strain CI 2366 strain was reduced only by GOS. Unlike GOS, 2 0-FL did not support the growth of any S. mutans strain. Neither 2 0-FL nor GOS
enhanced the adhesive properties of the S. mutans strains, but they inhibited some of the tested strains. Thus, the cariogenic tendency may vary
between infant formulas containing different types of oligosaccharides.
Key words: 2 0-Fucosyllactose: Galacto-oligosaccharides: Streptococcus mutans: Human milk oligosaccharides: Xylitol:
Adhesion
Humanmilk oligosaccharides (HMOs), a diverse group of carbo-
hydrates, are the third most abundant component in human
milk(1). More than 150 HMO structures have been identified in
human breast milk, of which 2 0-fucosyllactose (2 0-FL; trisaccha-
ride of fucose, galactose and glucose) is the most abundant
HMO(1,2). The concentration of 2 0-FL in human milk is approx-
imately 2·7 g/l, although it can vary, depending on the time of
lactation(2). Only a small proportion of HMOs are absorbed,
andmost are fermented in the colon by the microbiota, primarily
by specific bifidobacteria, such as Bifidobacterium longum
subsp. infantis and Bifidobacterium bifidum(1). HMOs function
as selective prebiotics, improve immune development in the
host and inhibit the adhesion of certain pathogens in the
gut(1,3,4). Recent advances in the production of HMOs have
allowed 2 0-FL to be included in infant formulas to better approxi-
mate the composition of breast milk(5,6), since fucosylated oligo-
saccharides are nearly absent from bovine milk which is used as
basis for infant formulas(7). Galacto-oligosaccharides (GOS) are a
mixture of lactose-based oligosaccharides with varying lengths
and linkages between glucose and galactose, the terminal unit
being glucose(8). GOS are often used in infant formulas to mimic
the prebiotic features of human milk(8–10).
Dental caries is a common multifactorial disease, in which
bacteria in a biofilm produce acids that dissolve enamel(11).
Streptococcus mutans is one of the most extensively studied
cariogenic bacteria. S. mutans is well adapted to thrive under
biofilm conditions that alter bacterial metabolism and decrease
the susceptibility to host defence and antimicrobials(11–13).
S. mutans produces acids efficiently, creates a low-pH environ-
ment, utilises various carbon sources and can adhere to the tooth
surface through the production of extracellular glucans and
adhesins(11,14). The acquisition of mutans streptococci (i.e.
S. mutans and Streptococcus sobrinus) at an early age is a risk
factor for caries development later in life, the risk of which can
be decreased through caries prevention strategies early in the pre-
natal and postnatal phases(15,16). Several mechanisms have been
proposed to interfere with the virulence of S. mutans, such as
inhibiting adhesion, preventing growth through non-fermentable
carbon sources and affecting biofilm formation(17,18). There are
limited data on the effects of HMOs and GOS on S. mutans
Abbreviations: 2 0-FL, 2 0-fucosyllactose; BHI, Brain Heart Infusion medium; HMOs, human milk oligosaccharides; GOS, galacto-oligosaccharides; HA, hydroxy-
apatite; TSB, Tryptic Soy Broth.
* Corresponding author: K. Salli, email krista.salli@dupont.com
British Journal of Nutrition (2020), 124, 824–831 doi:10.1017/S0007114520001956
© The Author(s), 2020. Published by Cambridge University Press. This is an Open Access article, distributed under the terms of the Creative
Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction
in any medium, provided the original work is properly cited.
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and other oral bacteria. However, GOS are structurally different
from the oligosaccharides naturally occurring in human milk(19).
Breast milk components can alter the composition of the oral
microbiota, several of which have been examined with regard
to their effects on growth, adhesion and biofilm formation in
S. mutans(20–22). Infant formulas contain caries-protective com-
ponents, such as proteins and Ca, but the carbohydrates in them
may increase the risk for caries, especially if bottle feeding is tak-
ing place ad libitum, several times a day.
Because GOS and, increasingly, HMOs are added to infant
formulas, there is an urgent need to determine the influence
of these carbon sources on cariogenic bacteria and how they
affect the bacterial colonisation on teeth. We hypothesised that
mutans streptococci can use HMOs and GOS as sources of
carbohydrate to increase their growth and adhesion. Thus, the
aim of the present study was to examine whether a specific
HMO, 2 0-FL and GOS – in the form of a commercial prebiotic –
shape the growth and adhesion of three strains of the dental
pathogen S. mutans in vitro and compare the results to those
of xylitol and lactose.
Materials and methods
Micro-organisms
Three strains of S.mutanswere tested: the type strainDSM20523
(ATCC 25175), Ingbritt and the clinical isolate CI 2366. The ori-
gin, isolation and identification of the clinical isolate have been
described earlier(23,24).
Test substrates
A 10% (w/v) suspensionof 2 0-FL (DuPontNutrition&Biosciences
and Inbiose), xylitol (DuPont Nutrition & Biosciences), glucose
(J. T. Baker), lactose (Sigma-Aldrich) and GOS (kindly provided
by Clasado Biosciences) were prepared in sterile water,
sterile-filtered (0·2 μmMinisart; Sartorius AG) and stored at −20°C
until use.
Growth experiments
Bacterial growth experiments were performed as previously
described(25). Briefly, S. mutans strains were revived from frozen
(−70°C) stocks and subcultured in glucose-containing Brain
Heart Infusion medium (BHI) (LAB049; LabM Ltd) or Tryptic
Soy Broth (TSB) (Bacto™; Becton Dickinson and Company) at
37°C overnight. After the subculture, bacteria were inoculated
in fresh TSB growth medium with glucose and incubated at
37°C overnight. Cell suspensions (1 % (v/v)) were prepared in
modified TSB without carbohydrates and used immediately
for the growth assays.
2 0-FL, xylitol, GOS, lactose or glucose solution (10 %) were
added to each well of the plate (20 μl), and the wells were filled
with suspensions of a single bacterial strain (180 μl). Thus, the
final concentration of the carbohydrate substrate in each well
was 1 % (w/v). Modified TSB without any added carbohydrates
(sterile water was added instead of test substances) was used as a
control. Bacterial growth was monitored by measuring the opti-
cal density at 600 nm every 30 min for 24 h on a Bioscreen©
C system (Labsystems) in an anaerobic cabinet (80 % N2, 10 %
CO2, 10 % H2). The area under the growth curve over 24 h
was used to quantify growth(25). Three independent experi-
ments, each performed in triplicate, were run.
Adhesion to hydroxyapatite
Adhesion to hydroxyapatite (HA) was evaluated per Haukioja
et al.(26). Parotid saliva was collected on ice each morning before
the experiments using Lashley cups by stimulation with a Salivin
lozenge (Pharmacia Ltd). Parotid saliva was diluted 1:1 with buf-
fered KCl (50 mM KCl, 0·35 mM K2HPO4, 0·65 mM KH2PO4,
1·0 mM CaCl2, 0·1 mMMgCl2 and pH 6·5) before the experiments.
The diluted saliva was used to coat the HA powder (Clarkson
Chromatography Products Inc.), after which the HAwas washed
three times before bacteria were added. S. mutans was first
grown overnight in BHI (Becton Dickinson) at 37°C and then
for 3–4 h until the mid-logarithmic phase with 5 μl (50 μCi)
35S-labelled methionine (Perkin Elmer LifeSciences, Inc.). After
growth, the bacteria were washed three times and suspended
in phosphate-buffered KCl to approximately 108 colony-forming
units/ml. Suspensions (125 μl) of labelled bacteria and 1 % (w/v)
2 0-FL, xylitol, GOS, lactose and plain buffer as a control were
added to HA, to which the bacteria were allowed to adhere
for 60 min under gentle agitation (IKA loopster; IKA®-Werke
GmbH & Co. KG). Unbound bacteria were removed through
three washes with 125 μl buffer. Labelled bacteria that adhered
to HA were determined on a scintillation counter (MicroBeta
1450; Perkin Elmer Wallac) using scintillation cocktail
(Optiphase Supermix/Optiphase Hisafe 3; PerkinElmer).
Experiments were performed in six replicate wells (of which
the lowest and highest values of scintillation countswere omitted
to decrease variability; four replicates per individual experiment
were used) and repeated at least twice. To combine experi-
ments, the controls were set to 1, and the relative changes from
the control were calculated.
Adhesion to glass surface
Exopolysaccharide-mediated adhesion of S. mutans strains to a
smooth glass surface was examined per Mattos-Graner et al.(27).
S. mutans was first grown in BHI (LabM Ltd) at 37°C overnight.
Then, triplicate samples were cultured in BHI with 1 % (w/v)
sucrose (Suomen Sokeri Oy) and 1 % (w/v) 2 0-FL, xylitol,
GOS, lactose or plain buffer in a glass tube at a 30° angle in
an anaerobic atmosphere at 37°C for 18 h. The control sample
was comprised of BHI with sucrose. After incubation, the tubes
were mixed gently, and unbound bacteria were transferred to
another tube (planktonic bacteria). The glass tubes were rinsed
with potassium phosphate buffer (0·05 mol/l, pH= 7) and
remixed, and unbound bacteria were again transferred to the
tube with planktonic bacteria. Then, potassium phosphate
buffer was added to the glass tubes to quantify the bacteria that
adhered to the glass. The planktonic bacteria tubes were centri-
fuged 6500 rpm for 5 min (Heraeus Biofuge Stratos, Kendro
Laboratory Products), and the pellets were resuspended in
potassium phosphate buffer. All tubes were vortexed and soni-
cated for 30 s (Q Sonica Sonicator LCC), and OD550 (optical den-
sity at wavelength of 550 nm) values were measured against
Influence of 2 0-fucosyllactose and galacto-oligosaccharides on Streptococcus mutans 825
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potassium phosphate buffer on an Ensight plate reader (Perkin
Elmer). The percentage of adherent bacteria was calculated
as the ratio of adhered bacteria to all bacteria. The data are the
composite of three independent experiments. In each experi-
ment, the treatments were performed in triplicate. To combine
and compare the experiments, the controls were set to 1, and
the relative changes from the control were determined.
Statistics
In growth experiments, statistical differences between treatment
groups were analysed by one-way ANOVA and Dunnett’s
multiple comparison test. In adhesion experiments, statistical
differences between treatment groups were analysed by one-
way ANOVA and Tukey’s multiple comparison test. The statisti-
cal analysis was performed using GraphPadPrism version 8.1 for
Windows (GraphPad Software). P values of <0·05 were consid-
ered to be significant.
Results
S. mutans strains DSM 20523, CI 2366 and Ingbritt were unable
to grow with 2 0-FL as the sole carbon source, comparable with
the result when no carbon source was added to the TSB growth
medium (P> 0·05 for all strains, Fig. 1). In contrast, all S. mutans
strains grewwith 1 %GOS, 1 % lactose or 1 % glucose as a carbon
source (P< 0·001, for all strains). Xylitol inhibited the growth of
all three S. mutans strains v. the control without any added
carbohydrates (P< 0·05, Fig. 1).
The effects of 2 0-FL, xylitol, GOS and lactose on S. mutans
adhesion to parotid saliva-coated HA were evaluated (Fig. 2).
There were no significant changes in strains DSM 20523 or
Ingbritt v. the control with any of the carbohydrates (P> 0·05).
Nevertheless, the adhesion of strain CI 2366 decreased signifi-
cantly with 2 0-FL and GOS compared with the control
(P< 0·001 and P= 0·04, respectively).
The effects of 2 0-FL, xylitol, GOS and lactose on S. mutans
adhesion to a glass surface – indicative of hydrophilic binding
through exopolysaccharides – were also evaluated. The
adhesion of strain DSM 20523 was reduced by 2 0-FL (P= 0·02),
lactose (P< 0·001) and GOS (P< 0·001) v. the control (Fig. 3).
The adhesion of strain Ingbritt to glass was unaffected by any
of the carbohydrates (P> 0·05), whereas that of strain CI 2366
decreased only with GOS (P= 0·02) (Fig. 3).
Discussion
Human breast milk contains caries-protective factors(28–30), but
the effects of individual HMOs on oral health-related variables
have not been reported. Our study is the first report on the effects
of an individual HMOon S.mutans, an oral bacterium associated
with the pathogenesis of caries. None of the three S. mutans
strains that we tested utilised 2 0-FL as a carbon source, whereas
they grew well with GOS, lactose and glucose. S. mutans is well
adapted to thrive in the oral cavity and canmetabolise many car-
bon sources(11,23,31,32). Thus, we aimed to determine whether
S. mutans grows on HMOs and other prebiotics, such as GOS,
which are also added to infant formulas. 2 0-FL has been studied
in infant formula at 0·2–1 g/l, for other health indications than
oral health, as have GOS levels at 0·2–0·5 g/dl(5,6,9,10,33). The
2 0-FL concentrations that we tested exceeded those in infant for-
mula and were slightly higher than GOS concentrations.
Our results are consistent with earlier studies showing that
S. mutans utilise galactose, lactose and glucose(31,32). Although
limited data exist regarding GOS and cariogenic bacteria,
S. mutans strain MT8148R (serotype c) was found earlier to fer-
ment GOS similarly to our strains in the present study(34). As
reported at low xylitol concentrations, xylitol inhibited the
growth of planktonic S.mutans strains(23). Thus, while S.mutans
can grow on glucose and galactose, the building blocks of
both lactose and GOS, it failed to grow with the trisaccharide
2 0-FL. The structure of 2 0-FL contains fucose attached to lactose
with α-1,2 linkage(1). GOS are a mixture of varying length galac-
tose units with lactose at the reducing end,with glycosyl linkages
commonly either β-1,3, β-1,4 or β-1,6 depending on the enzyme
used(35). The growth of oral pathogens has not earlier been stud-
ied with HMOs, but potentially pathogenic Enterobacteriaceae
and Clostridium perfringens did not grow using 2 0-FL(36,37).
In addition, pooled HMOs have been shown to inhibit the
growth of Streptococcus agalactiae CNCTC 10/18 (group B
Streptococcus)(38). However, the inhibition rate varied depend-
ing on HMO donors (and thereby the HMO composition).
Degradation of HMOs requires an extensive set of glycoside
hydrolases, membrane transporters and carbohydrate binding
proteins(39). Absence of these key proteins has been shown to
result in the lack of ability to grow on HMOs. Bacteria, such
as bifidobacteria or Bacteroides, which are able to grow with
HMOs like 2 0-FL, mainly apply one of the two strategies.
B. longum subsp. infantis has several glycoside hydrolases,
ATP binding cassette (ABC) transporters and extracellular solute
binding proteins, it utilises to import HMOs into the cell and
degrade oligosaccharides intracellularly(39–41). Bacteroides, on
the other hand, have been proposed to degrade complex
HMOs partly and then transport processed oligosaccharides
inside the cell for further degradation(39). The α-1,2-fucosidase
is required for utilising 2 0-FL. However, its presence does not
always show as utilisation of 2 0-FL(42). Recently, Streptococcus
pneumoniae has been shown to contain two α-fucosidases(43).
The genome sequence of S. mutans strain UA159 is known to
have four ABC transporters(44), but transcription profiles for
fucose or HMOs were not studied. Our results indicate that
the studied S. mutans strains do not express the enzymes or
other factors required to metabolise α-1,2 fucosylated carbohy-
drates. Consequently, 2 0-FL should have no negative impact on
the cariogenic potential of infant formulas, whereas other less
selective prebiotic oligosaccharides may have.
The two adhesion experiments showed no consistent pat-
terns of inhibition for 2 0-FL or GOS. Notably, the adhesion of
the virulent clinical isolate S. mutans Cl 2366(24) to saliva-coated
HAwas reduced by 2 0-FL and GOS. Further, exopolysaccharide-
mediated adhesion to the glass surface decreased for S. mutans
DSM 20523 with 2 0-FL and GOS. HMOs have been suggested to
function in the gut as selective prebiotics, antimicrobials, to
inhibit the adhesion on colonic epithelium of some pathogens,
for example, Escherichia coli, Campylobacter jejuni or
protozoan parasite like Entamoeba histolytica and to modify
826 K. Salli et al.
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2'-
FL
Xy
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l
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S
La
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B
& i
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2'-
FL
Xy
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GO
S
La
cto
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Gl
uc
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TS
B
& i
no
cu
la
TS
B
& n
o i
no
cu
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2'-
FL
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cto
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e
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& i
no
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B
& n
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la
200
0
200
400
600
800
AU
C
(a)
*
** ** **
0·0
0·2
0·4
0 10 20 30
0·6
0·8
1·0
Time (h)
O
D
60
0
(d)
200
0
200
400
600
800
1000
AU
C *
(b)
0·0
0·5
1·0
1·5
Time (h)
O
D
60
0
(e)
200
0
200
400
600
800
AU
C *
(c)
0·0
0·2
0·4
0·6
0·8
1·0
Time (h)
O
D
60
0
(f)
0 10 20 30
0 10 20 30
** ** **
** ** **
Fig. 1. Area under the growth curve (AUC) (a–c) and growth curves (e and f) of Streptococcus mutans strains DSM 20523 (a and d), CI 2366 (b and e) and Ingbritt
(c and f). Growth media contained 1% (w/v) 2 0-fucosyllactose (2 0-FL), xylitol, galacto-oligosaccharides (GOS), lactose or glucose added to modified Tryptic Soy Broth
(TSB−) devoid of glucose or other carbon sources. Values are means and standard deviations from three individual experiments, each with three replicates. * P< 0·05;
**P< 0·001 compared with TSB− and inocula. OD, optical density. , 2 0-FL; , xylitol; , GOS; , lactose; , glucose; , TSB− and inocula; , TSB− and no inocula.
Influence of 2 0-fucosyllactose and galacto-oligosaccharides on Streptococcus mutans 827
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host responses(1,45). However, their effects are structure- and
bacterium-specific(3,4,45). HMOs have structural similarities to
glycan structures in the gut epithelium, and they can function
as decoy receptors, hindering the binding of pathogens(4,45).
To our knowledge, the effects of HMOs on adhesion to oral bac-
teria have not been studied before. The binding of S. mutans
with substrates in salivary pellicle is mediated by sucrose-
independent, adhesin-receptor interactions(11,26). The adhesion
of the two reference strains to saliva-coated HA was not signifi-
cantly affected by 2 0-FL or GOS, but both compounds signifi-
cantly decreased the adhesion of strain CI 2366(24). Earlier,
other components of humanmilk casein, IgA and IgG have been
shown to decrease the adhesion of S. mutans to saliva-coated
HA(21,22). Also, in earlier studies, changes in adhesion have been
observed between S. mutans strains(21).
Adhesion to a smooth glass surface, reflecting sucrose-
dependent, extracellular glycan production-mediated
adherence(11,27,34), decreased or was unchanged with 2 0-FL
and GOS. These results are consistent with those from a similar
experiment, showing that the adherence of S. sobrinus 6715 and
S. mutans MT8148R was impeded by GOS(34). However, for
2 0-FL, our work is the first report to document the effects on exo-
polysaccharide-mediated adhesion in S. mutans. The two meth-
ods used in the present study evaluated two different S. mutans
virulence factors. However, because of the strain-dependent
variation in the results, further research is needed to clarify
the effects of 2 0-FL and other HMOs on S. mutans and other oral
bacteria.
Xylitol did not affect the adhesion of S. mutans in any exper-
imental setting, although its chemical properties may have sug-
gested so. Xylitol binds water molecules and Ca ions, among
other compounds, but is inert in other aspects(46). The effects
of xylitol on adhesion have never been studied in such a design
as ours. Based on earlier studies, we expected that xylitol would
interfere with polysaccharide-mediated cell adherence(24,47), but
we found no significant differences in adhesion at studied xylitol
concentration. Also, adhesion to parotid saliva-coated HA was
unaffected by xylitol.
S. mutans forms a small portion of the developing oral
microbiota – if it is present at all(48) – and expanding our studies
to other oral pathogens and commensals could provide a
broader understanding of the effects of HMOs and GOS. In addi-
tion, biofilm formation could have been evaluated to increase
understanding beyond initial stages of colonisation. Human
breast milk increases S. mutans biofilm formation, whereas
individual milk components have various effects, with casein
increasing and lactoferrin and IgA (the latter at high concentra-
tions) decreasing biofilm formation and lactose having no
Ct
rl
2'-
FL
Xy
lito
l
GO
S
La
cto
se
Ct
rl
Xy
lito
l
GO
S
La
cto
se
Ct
rl
Xy
lito
l
GO
S
La
cto
se
0.0
0.5
1.0
S. mutans DSM20523
R
el
at
iv
e 
ad
he
si
on
2'-
FL
0.0
0.5
1.0
1.5
2.0
S. mutans  Ingbritt
R
el
at
iv
e 
ad
he
si
on
2'-
FL
0.0
0.5
1.0
1.5
S. mutans  CI2366
R
el
at
iv
e 
ad
he
si
on
*
*
Fig. 2. Relative adhesion to parotid saliva-coated hydroxyapatite (HA) for three Streptococcus mutans strains (DSM 20523, Ingbritt and CI 2366) with 1% (w/v) 2 0-
fucosyllactose (2 0-FL), xylitol, galacto-oligosaccharides (GOS), lactose and phosphate buffer as a control (Ctrl). Bacterial adhesion to HAwas determined by scintillation
count. *P< 0·05 compared with control.
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effect on it(20). However, although the proportion of mutans
streptococci in the oral microbiota may be small, they are viru-
lent cariogenic bacteria and key factors in dental caries(12),
underscoring the importance of our findings. Xylitol was used
as a reference substance, because it is a prebiotic(49) and
because its effects on reducing growth and adherence of mutans
streptococci arewell documented(18); and lactose, because it is the
major carbohydrate component in breast milk and infant
formulas(50,51). Growthwas assessed continuously, and adherence
to parotid saliva-coated HA surfaces and exopolysaccharide-
mediated adhesion to a glass surface was evaluated.
Within the limitations of the present study, we showed that
2 0-FL and GOS strain-dependently decrease S. mutans adhesion
or have no effects on it. 2 0-FL was not utilised by the S. mutans
strains that we tested, whereas they grewwell with GOS and lac-
tose. Delaying the early colonisation of S. mutans decreases the
future risk of caries in children(15,16). Thus, 2 0-FL, as a compound
that is present at high concentrations in human breast milk, may
be beneficial for the oral health of infants by not promoting
S. mutans adhesion. Also, being non-fermentable by S. mutans,
2 0-FL may decrease acid production in the dental plaque, if it has
already colonised erupting teeth. In the limits of this in vitro
study, and in the perspective of caries pathogenesis, it can be
concluded that the ability of 2 0-FL to limit the growth and inhibit
the adhesion of S. mutans may bring an advantage to use this
milk oligosaccharide in infant formulas.
Acknowledgements
Katja Sampalahti, University of Turku, Institute of Dentistry,
Turku, Finland, is acknowledged for her skilful technical assis-
tance in HA adhesion. The authors thank Kirsi Stenström and
Terhi Koskela from DuPont Nutrition & Biosciences, Kantvik,
Finland, for their excellent assistance in bacterial growth experi-
ments. The studies presented in this publicationwere sponsored,
in their entirety, by DuPont Nutrition & Biosciences. Hence,
DuPont Nutrition & Biosciences has the sole proprietary owner-
ship of the results. The data may be used in regulatory filings, by
DuPont Nutrition & Biosciences, to obtain regulatory approvals
for the 2 0-FL product. The use of the results in this publication
by stakeholders for regulatory filings, other than DuPont
Nutrition & Biosciences, require a written approval by DuPont
Nutrition & Biosciences.
This work was funded by the DuPont Nutrition & Biosciences.
K. S., J. H. and A. C. O. are employed by DuPont Nutrition &
Ct
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Xy
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La
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2'-
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Xy
lito
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GO
S
La
cto
se
Ct
rl
2'-
FL
Xy
lito
l
GO
S
La
cto
se
0.0
0.5
1.0
1.5
S. mutans DSM20523
R
el
at
iv
e 
ad
he
si
on
*
*
*
0.0
0.5
1.0
S. mutans Ingbritt
R
el
at
iv
e 
ad
he
si
on
0.0
0.5
1.0
S. mutans CI2366
R
el
at
iv
e 
ad
he
si
on
*
Fig. 3. Relative adhesion of three Streptococcus mutans strains (DSM 20523, Ingbritt and CI 2366) to a glass surface. S. mutans strains were cultured in Brain Heart
Infusion medium with 1% (w/v) sucrose and 1% (w/v) 2 0-fucosyllactose (2 0-FL), xylitol, galacto-oligosaccharides (GOS), lactose and buffer as a control (Ctrl). *P< 0·05
compared with control.
Influence of 2 0-fucosyllactose and galacto-oligosaccharides on Streptococcus mutans 829
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Biosciences and contributed to the study design, conduct of the
study, analysis of the samples and data, interpretation of the find-
ings and preparation of the manuscript.
K. S., J. H. and A. C. O. are employees of DuPont, which
manufactures and sells 2 0-FL under the brand Care4U™.
All authors formulated the research question and designed
the study, K. S. performed the experimental work and drafted
the manuscript and all analysed the data and reviewed manu-
script writing. All the authors read and approved the final version
of the manuscript.
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