Chemistry Reference
In-Depth Information
Table 6.2 Concentration of Total Carbohydrate residues after bacterial
growth for 48 h in Autoclaved basal Medium Containing glucose,
Amylopectin, and hACs) granules (Mean Concentration, Mg/Ml, 6
sD in Medium Conta
i
ning glucose, Amylopectin, hACs)
glucose
Amylopectin
hACs
Bifidobacterium bifidum
4.05
5.30
6.96
Bifidobacterium pseudolongum
4.64
5.47
7.53
Bacteroides vulgatus
7.08
10.23
9.66
Bacteroides fragilis
7.12
7.86
8.86
Eubacterium limosum
5.39
9.97
10.99
Note:
total carbohydrates were measured by using the dubois method and are the
means of two determinations from four individual experiments. the initial total
carbohydrate concentration was 12 mg/mL.
Source:
adapted from Wang et al., 1999.
of bifidobacteria and lactobacilli species and lowered pH levels and numbers of total
coliforms as compared with the low-RS diet (no supplemented RS). The moderate-RS
diet also increased cell proliferation and crypt column height. Bifidobacteria bind to
HACS granules, which increases survival at pH 6.5, pH 3.5, and under bile salt condi-
tions (Wang et al., 1999b).
Lesmes et al. (2008) studied the possible effects of RS3 crystalline polymor-
phism on RS fermentability by human gut microbiota and the SCFAs production
in
vitro
. Human fecal pH-controlled batch cultures showed that RS induces an ecologi-
cal shift in the colonic microbiota. Polymorph B promoted the growth of bifidobac-
teria in the proximal part of the colon and double their relative proportion in the
microbiota in the distal colon while increasing butyrate production to levels of 0.79
m
M
. Among several bifidobacteria strains, the preparations obtained from normal
and waxy cornstarches were the best substrates for growth of
B. breve
KN14, even
compared with glucose (Wronkowska et al., 2008).
In pigs, HACS (85 percent amylose) and hydrothermally treated HACS increased
fecal and proximal colonic lactobacilli and bifidobacteria numbers by 1 and 3 log
units (
P
< 0.05) (Brown et al., 1997; Bird et al., 2007). One human study reported
that RS2 increased fecal bifidobacteria measurements (Brown et al., 1998).
6.4 rs As PrEbIoTIC AND syNbIoTIC
Probiotics are defined as live microorganisms that are administered in ade-
quate amounts to help beneficial intestinal microflora grow (Topping et al., 2003).
Prebiotics are nondigestible substances that provide a beneficial physiological effect
on the host by selectively stimulating the favorable growth or activity of a limited
number of indigenous bacteria. Roberfroid (1998) and Nakanishi et al. (2003) have
proposed the term synbiotics or symbiotics, a combination of a probiotic and a pre-
biotic because synbiotics or symbiotics are more potent than either a probiotic or
