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certain polyphenols such as proanthocy-
anidins have been investigated. Proanthocy-
anidins, also called condensed tannins, are
polymers that have a long history of use in
tanning of animal skins, and they are deter-
minants of flavour and astringency in teas,
wines and fruits.
Cranberry juice has been studied for its
anti-
H. pylori
properties. Preliminarily,
Burger and coworkers (2000, 2002) reported
that high molecular weight constituents of
cranberry juice inhibited the sialic specific
bind of
H. pylori
to gastric mucus and
mucosal cells
in vitro
. Importantly, this
inhibitory effect also was observed for met-
ronidazole- and clarithromycin-resistant
strains of
H. pylori
(Chatterjee
et al.
, 2004;
Shmuely
et al.
, 2004). The efficacy of cran-
berry juice against
H. pylori
was tested clin-
ically in a study with 189 infected patients
(Zhang
et al.
, 2005) and also in combination
with antibiotics and proton pump inhibi-
tors (Shmuely
et al.
, 2007). One half of these
individuals (
H. pylori
positive by a
13
C-urea
breath test) drank 250 ml of cranberry juice
daily for 90 days, whereas the others
received a placebo drink. After 35 and
90 days, fewer patients tested positive for
H. pylori
in the cranberry juice group.
The intake of cranberry juice in combina-
tion with probiotics (
Lactobacillus johnsonii
La1) has been investigated recently by
Gotteland and coworkers (2008). In this study,
295 asymptomatic children (6-16 years old)
who tested positive for
H. pylori
by the
13
C-urea breath test (UBT) received cranberry
juice, La1, placebo or a combination of cran-
berry juice and La1. Eradication rates were
significantly different in the four groups sug-
gesting that a regular intake of cranberry juice
or La1 could help with the management of
H. pylori
infection in children. Also, some
studies reported that cranberry juice associ-
ated with other antioxidant-rich sources (
Vitis
vinifera
; blueberries and oregano) inhibits the
grown of
H. pylori
in a synergistic fashion
(Lin
et al.
, 2005; Vattem
et al.
, 2005a).
Rohdewald and Beil (2008) demonstrated
recently that a pine bark proanthocyanidin-
rich extract (Pycnogenol
®
) concentration-
dependently inhibited the
H. pylori
adhesion
to AGS cells.
On the basis of the above findings, our
group recently evaluated an apple peel
polyphenol-rich extract (APPE, 24% procy-
anidins), against
H. pylori
adherence and
vacuolation in HeLa cells (Pastene
et al.
,
2010). We found that APPE exerted dual
anti-
H. pylori
effects, inhibiting the process
of adherence of the bacteria to gastric
mucosa and also the activity of VacA pro-
tein. The anti-adherence effect was limited,
however, because the mean degree of poly-
merization (
DPm
) of APPE is ~3. This
DPm
is lower than that reported for other sources
such as pine bark (8-10) or persimmons
(19-47) (Jerez
et al.
, 2007; Li
et al.
, 2011).
So, the APPE anti-adherence effect was
observed at an IC
50
value of 5.3 mg of gallic
acid equivalents per ml (GAE/ml). This
result suggested to us that the source and
methodology of procyanidin extraction are
very important. Using solid-state bio-
processing (with
Rhizopus oligosporus and
Lentinus edodes
fungi), a group of research-
ers were able to increase the extraction yield
of polyphenols from cranberry pomace,
obtaining a product with higher anti-
H. pylori
activity (Vattem
et al.
, 2005b). In a
similar approach, from bio-processed pine-
apple wastes (
Ananas cosmosus
), other
researchers found extracts (enriched in
quercetin and biphenyl structures) with a
potent anti-
H. pylori
effect (Correia
et al.
2004). In the latter study, however, the anti-
oxidant capacity of the extracts did not cor-
relate with the anti-
H. pylori
activity.
In a recent study, the antimicrobial
activity of 12 types of Nordic berries was
evaluated on various human pathogens. In
this work,
H. pylori
and
Bacillus cereus
were the most sensitive pathogens assayed.
Interestingly, although it was observed that
the levels of polyphenols decreased during
cold storage, the antimicrobial activity was
not significantly modified (Nohynek
et al.
,
2006). Considering the elevated polyphe-
nolic contents found in tea, its anti-
H. pylori
effects also have been investigated.
In vitro
studies using 5% infusions of green tea
(
Lung Chen
, cv) showed inhibition of
H. pylori
multiplication, suggesting that
such activity would reside in the presence
of the flavan-3-ol known as epigallocatechin
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