Synergistic impact of whole grain (WG) and resistant starch (RS) components from high‐amylose maize ‐ effects on fermentation in the Zucker Diabetic Fatty (ZDF) rat

Abstract

Previously, RS has increased gut fermentation in several rodent models including the non‐obese type 2 diabetic Goto Kakazaki rat. We investigated if the obese ZDF rats would respond to RS with fermentation in the cecum with increased cecal weights (marker of fermentation) and would RS in whole grain flour have a greater effect. There were 4 groups: Amioca control (AC), RS, dent WG control (DWGC), and WGRS (first three groups n=12, WGRS n=11). The signifying diet components, Amioca starch, high amylose maize starch, dent corn flour and WG high amylose maize flour, were analyzed by proximate analysis and modified Englyst assay for formulating diets for macronutrient content and RS amount, respectively. The RS by weight of the final diets was: AC 0%, DWGC 6.9%, RS 25%, and WGRS 25%. Results were significant if p<0.05. Cecal weights (g) were significantly different among all groups: AC 0.46, DWGC 0.55, RS 0.87, and HMWG 1.14±0.03. These increased cecal weights showed that ZDF rats fermented RS and that the combination of WG and high RS has a 30% greater effect than RS without WG. This synergistic effect is evidence for greater possible health benefits of WG. Funding sources: Ingredion, Inc. and LSU AgCenter.