Butyrate and other SCFA produced by bacterial fermentation of resistant starch (RS) or nonstarch polysaccharides (NSP) promote human colonic health. To examine variation in fecal variables, especially butyrate, among individuals and the response to these fibers, a randomized cross-over study was conducted that compared the effects of foods supplying 25 g of NSP or 25 g of NSP plus 22 g of RS/d over 4 wk in 46 healthy adults (16 males, 30 females; age 31-66 y). Fecal SCFA levels varied widely among participants at entry (butyrate concentrations: 3.
View Article and Find Full Text PDFEpidemiological studies have suggested that dietary fibre lowers the risk of colorectal cancer, which may be due to increased butyrate production from colonic fermentation of a type of fibre, resistant starch (RS). The present study investigated the effects of dietary RS and butyrylated RS on the faecal microbiota of rats treated with azoxymethane. A total of four groups of nine rats were fed diets containing either standard maize starch (low-amylose maize starch (LAMS), low RS), LAMS with 3 % tributyrin (LAMST), cooked 10 % high-amylose maize starch (HAMS, high RS) or cooked 10 % butyrylated HAMS (HAMSB).
View Article and Find Full Text PDFTo further understand how diets containing high levels of fibre protect against colorectal cancer, we examined the effects of diets high in nonstarch polysaccharides (NSP) or high in NSP plus resistant starch (RS) on the composition of the faecal microbial community in 46 healthy adults in a randomized crossover intervention study. Changes in bacterial populations were examined using denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments. Bacterial profiles demonstrated changes in response to the consumption of both RS and NSP diets [analysis of similarities (ANOSIM): R=0.
View Article and Find Full Text PDFProliferative enteropathy is an important enteric disease caused by Lawsonia intracellularis. A wide range of host species can be infected by the same bacterium, yet the clinico-pathologic features among these hosts remains almost identical. The disease has been recognized regularly among ratites, but not in other avian families, such as galliforms, even though these suffer uncharacterized enteric conditions.
View Article and Find Full Text PDFThe purity of DNA extracted from faecal samples is a key issue in the sensitivity and usefulness of biological analyses such as PCR for infectious pathogens and non-pathogens. We have compared the relative efficacy of extraction of bacterial DNA (both Gram negative and positive origin) from faeces using four commercial kits (FastDNA kit, Bio 101; Nucleospin C+T kit, Macherey-Nagal; Quantum Prep Aquapure Genomic DNA isolation kit, Bio-Rad; QIAamp DNA stool mini kit, Qiagen) and a non-commercial guanidium isothiocyanate/silica matrix method. Human faecal samples were spiked with additional known concentrations of Lactobacillus acidophilus or Bacteroides uniformis, the DNA was then extracted by each of the five methods, and tested in genus-specific PCRs.
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