Articles Researching Barley and Beta-Glucan

Abstract
BBn (BioBreeding) rats were fed casein-based diets supplemented with barley flour,
oatmeal flour, cellulose, or barley -glucans of high [HV] or low viscosity [LV] in order
to measure the prebiotic effects of these different sources of dietary fiber. The dietary
impact on the composition of the cecal microbiota was determined by the generation of
denaturing gradient gel electrophoresis (DGGE) profiles of PCR-amplified 16S rRNA
gene sequences. The DGGE profiles produced from the cecal microbiota of rats within
each dietary group were similar, but consensus profiles generated from pooled bacterial
DNAs showed differences between rat groups.Animals fed HV glucans (HV-fed rats)
had DGGE consensus profiles that were 30% dissimilar from those of the other rat
groups. A 16S rRNA gene fragment that was more conspicuous in the profiles of HV-fed
animals than in those of cellulose-fed rats had sequence identity with Lactobacillus
acidophilus. Measurements of L. acidophilus rRNA abundance (DNA-RNA
hybridization), the preparation of cloned 16S rRNA gene libraries, and the enumeration
of Lactobacillus cells (fluorescent in situ hybridization) showed that lactobacilli formed a
greater proportion of the cecal microbiota in HV-fed rats. In vitro experiments confirmed
that some lactobacilli utilize oligosaccharides (degree of polymerization, 3 or 4) present
in -glucan hydrolysates. The results of this study have relevance to the use of purified glucan
products as dietary supplements for human consumption.

Click Here for the PDF

» View All