Prebiotic Dose Studies 1987-2008

1987 Effect of fructo-oligosaccharides
on intestinal microflora
http://onlinelibrary.wiley.com/doi/10.1002/food.19870310528/abstract

In the experiment with 23 patients (73 ± 9 years old),
improvement of fecal microflora
was observed by oral administration
of fructo-oligosaccharides 8 g per day for two weeks:
the population of bifidobacteria in feces
increased about 10 times compared before the administration;
average pH of stool showed 0.3 lower than that before administration.

1990 Effects of Soybean Oligosaccharides on Human Faecal Flora
http://informahealthcare.com/doi/abs/10.3109/08910609009140252

A purified stachyose and raffinose fraction
of soybean oligosaccharides was fermented in vitro
by Bifidobacterium spp., although not B.bifidum, and
fermented to a limited degree
by Lactobacillus salivarius,
Mitsuokella multiacida and the
Bacteroides fragilis group,
but was not fermented by other bacteria.

Six healthy adult males (28–48 yr of age)
ingested 10 g of soybean oligosaccharides extract
(SOE; 23 per cent stachyose and 7 per cent raffinose) daily
independently or in combination
with 6 ± 109 [6 Billion] colony forming units (c.f.u.)
of B.longum 105 for 3 wk.

During ingestion of SOE,
the number of bifidobacteria increased significantly.

2001 The prebiotic properties of oligofructose
at low intake levels
http://www.nrjournal.com/article/S0271-5317(01)00284-6/abstract

The specific objective of this study
was to investigate the effect of ingesting
a low dose of oligofructose (5 g/day)
by healthy human subjects on the faecal microflora,
especially bifidobacteria, and
to compare it with the ingestion of a placebo (sucrose).

In a placebo-controlled study design,
faecal samples were collected in the morning
from 8 healthy human subjects,
who were not on any medication, and
immediately enumerated
for bifidobacteria, Bacteroides, coliforms,
total anaerobes and total aerobes.

Subjects first took sucrose (placebo) daily (5 g) for 3 weeks
with their normal diet except for known sources
of oligofructose and inulin and
subsequently were administered
oligofructose (5 g) daily for 3 weeks.

Faecal samples were collected
after 11 days and after 3 weeks.
At 2 weeks post ingestion of oligofructose,
another set of faecal samples was taken.
All samples were subjected to immediate microbial enumeration.

Ingestion of sucrose (5 g/day)
was without effect on all faecal bacteria enumerated,
whereas consumption of oligofructose (5 g/day) for 11 days
resulted in close to one log cycle
increase in bifidobacteria numbers.
No further increase was observed after the next 10 days.

At 2 weeks after termination of oligofructose ingestion,
bifidobacteria numbers had decreased
to almost that of the period before treatment.
Increases in numbers of Bacteroides and
total anaerobic bacteria
but not in aerobic bacteria also occurred.


2002 Effect of pH and Dose on the Growth
of Gut Bacteria on Prebiotic Carbohydrates in vitro
http://www.sciencedirect.com/science/article/pii/S1075996402904348

The effect of pH and substrate dose
on the fermentation profile of a number
of commercial prebiotics was analysed in triplicate
using stirred, pH and temperature controlled
anaerobic batch culture fermentations,
inoculated with a fresh faecal slurry
from one of three healthy volunteers.

Bacterial numbers were enumerated
using fluorescence in situ hybridisation.
The commercial prebiotics investigated were
--fructooligosaccharides (FOS),
--inulin,
--galactooligosaccharides (GOS),
--isomaltooligosaccharides (IMO) and
--lactulose.

Two pH values were investigated,
i.e. pH 6 and 6.8.
Doses of 1% and 2% (w/v) were investigated,
equivalent to approximately 4 and 8 g per day, respectively,
in an adult diet.

It was found that both pH and dose
altered the bacterial composition.
It was observed that FOS and inulin
demonstrated the greatest bifidogenic effect
at pH 6.8 and 1% (w/v) carbohydrate,
whereas GOS, IMO and lactulose
demonstrated their greatest bifidogenic effect
at pH 6 and 2% (w/v) carbohydrate.

From this we can conclude that various prebiotics
demonstrate differing bifidogenic effects
at different conditions in vitro.

2007 Gum arabic establishes prebiotic functionality
in healthy human volunteers in a dose-dependent manner
The present study was undertaken
to determine the prebiotic efficacy of gum arabic
upon consumption by man for up to 4 weeks and,
if any, to establish the dose–effect relationship.

Human healthy volunteers consumed various daily doses
(5, 10, 20, 40 g) of gum arabic (EmulGoldw)
in water for up to 4 weeks.
Daily consumption of water was taken as the negative control and
that of 10 g inulin as the positive control.

At 0, 1, 2 and 4 weeks quantification of bacterial numbers
in stool samples was performed via real time-PCR techniques and questionnaires were filled in to account for potential drawbacks.

The genera of Bifidobacteria and Lactobacilli
were taken as potentially beneficial bacteria and
those of Bacteroides,
Clostridium difficile and
Enterococci
as potentially non-beneficial,
this distinction was dependent on the issue
of these numbers being or becoming out of balance in the host.

Compared with the negative control
the numbers of Bifidobacteria and Lactobacilli
4 weeks after consumption
were significantly higher for gum arabic:
the optimal dose being around 10 g.

Moreover, at this dose the numbers
of Bifidobacteria, Lactobacilli and Bacteroides
were significantly higher for gum arabic than for inulin.

No significant drawback was encountered during the study.
It is concluded that gum arabic establishes prebiotic efficacy,
at least as good as inulin.
The optimal daily dose was found to be 10 g.

2008 Clinical trial: the effects
of a trans-galactooligosaccharide prebiotic on faecal microbiota and symptoms in irritable bowel syndrome
http://www.bimuno.com/wp-content/uploads/2011/01/Silk-et-al-Aliment-Pharmacol...

To investigate the efficacy
of a novel prebiotic trans-galactooligosaccharide
in changing the colonic microflora and
improve the symptoms in IBS sufferers.

In all, 44 patients with Rome II positive IBS completed a 12-week single
centre parallel crossover controlled clinical trial.
Patients were randomized to receive either
--3.5 g⁄d prebiotic,
--7 g⁄d prebiotic or
--7 g⁄d placebo.

IBS symptoms were monitored weekly and
scored according to a 7-point Likert scale.
Changes in faecal microflora, stool frequency and
form (Bristol stool scale) subjective global assessment (SGA),
anxiety and Depression and QOL scores were also monitored.

The prebiotic significantly enhanced faecal bifidobacteria
(3.5 g⁄d P < 0.005; 7 g⁄d P < 0.001).

Placebo was without effect on the clinical parameters monitored,
while the prebiotic at 3.5 g⁄ d
significantly changed stool consistency (P < 0.05),
improved flatulence (P < 0.05)
bloating (P < 0.05),
composite score of symptoms (P < 0.05) and
SGA (P < 0.05).

The prebiotic at 7 g ⁄d
significantly improved SGA (P < 0.05) and
anxiety scores (P < 0.05).