Abstract
Whole grain (WG) and fat content of the diet have been previously shown to affect intestinal fermentation and phenotype conferred by high–amylose maize starch (HAM), a form of fermentable dietary fiber. The current study was designed to compare rodent gut health following consumption of whole grain and non–whole grain prebiotics on moderate fat (MF) and high fat (HF) diets using a 2x2x2 factorial design. MF and HF diets were prepared to contain the following diet sources: (1) control starch with no WG or RS [CON], (2) whole grain waxy corn flour with low RS [WWG], (3) purified HAM resistant starch (RS) [HAMRS], and (4) WG HAM flour rich in resistant starch (WG+RS) [HMWG]. The eight diet conditions were fed to Sprague Dawley rats for six weeks (n = 12 per group). After euthanasia, blood, cecal contents and cecal epithelial cells were collected and gastro–intestinal (GI) tract portions and fat pad (retroperitoneal, perirenal, and epididymal) weights recorded. The presence of purified RS2 resulted in greater fermentation as part of the RS*WG interaction whereas no WG with high RS had the lowest pH of cecal contents. There was a main effect of RS with the high RS groups having the lowest abdominal fat percent of body weight. The presence of WG resulted in consistency of fermentation as groups with WG had similar levels of short chain fatty acids with MF and HF diets as reflected by WG*FAT. No RS*FAT effect was observed because of the WG consistency. Also, a greater butyrate production with WG was demonstrated by RS*WG. Results were primarily driven by two major effects, reflected by the presence of and lack of some significant differences. Purified RS fermented better on MF than HF diets. Diets with RS+WG show similar fermentation on both types of diets. These effects may be driven by RS1 vs. RS2 as high RS2 ferments better with MF diets, but presence of RS1 may ferment better with HF diets.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have