Cereal Byproducts Have Prebiotic Potential in Mice Fed a High-Fat Diet

Summary, in English

Barley husks, rye bran, and a fiber residue from oat milk production were processed by heat pretreatment, various
separation steps, and treatment with an endoxylanase in order to improve the prebiotic potential of these cereal byproducts.
Metabolic functions were intended to improve along with improved microbial activity. The products obtained were included in a
high-fat mouse diet so that all diets contained 5% dietary fiber. In addition, high-fat and low-fat controls as well as partially
hydrolyzed guar gum were included in the study. The soluble fiber product obtained from rye bran caused a significant increase
in the bifidobacteria (log copies of 16S rRNA genes; median (25−75 percentile): 6.38 (6.04−6.66) and 7.47 (7.30−7.74),
respectively; p < 0.001) in parallel with a tendency of increased production of propionic acid and indications of improved
metabolic function compared with high-fat fed control mice. The oat-derived product caused an increase in the pool of cecal
propionic (from 0.62 ± 0.12 to 0.94 ± 0.08) and butyric acid (from 0.38 ± 0.04 to 0.60 ± 0.04) compared with the high-fat
control, and it caused a significant increase in lactobacilli (log copies of 16S rRNA genes; median (25−75 percentile): 6.83
(6.65−7.53) and 8.04 (7.86−8.33), respectively; p < 0.01) in the cecal mucosa. However, no changes in measured metabolic
parameters were observed by either oat or barley products.