The Metabolizable Energy of Dietary Resistant Maltodextrin Is Variable and Alters Fecal Microbiota Composition in Adult Men

• Published in: The Journal of nutrition Vol. 144; no. 7; pp. 1023 - 1029
• Main Authors: Baer, Davd J., Stote, Kim S., Henderson, Theresa, Paul, David R., Okuma, Kazuhiro, Tagami, Hiroyuki, Kanahori, Sumiko, Gordon, Dennis T., Rumpler, William V., Ukhanova, Maria, Culpepper, Tyler, Wang, Xiaoyu, Mai, Volker
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.07.2014; American Society for Nutrition
• Subjects: Adult; Bacterial Load; Bacteroides - growth & development; Bacteroides - isolation & purification; Bacteroides - metabolism; Bifidobacterium - growth & development; Bifidobacterium - isolation & purification; Bifidobacterium - metabolism; Biological and medical sciences; Clostridium - growth & development; Clostridium - isolation & purification; Clostridium - metabolism; Cross-Over Studies; Digestion; Double-Blind Method; Energy Metabolism; Feces - chemistry; Feces - microbiology; Feeding. Feeding behavior; Fermentation; Fundamental and applied biological sciences. Psychology; Gram-Negative Bacteria - growth & development; Gram-Negative Bacteria - isolation & purification; Gram-Negative Bacteria - metabolism; Gram-Positive Bacteria - growth & development; Gram-Positive Bacteria - isolation & purification; Gram-Positive Bacteria - metabolism; Humans; Intestinal Mucosa - metabolism; Intestinal Mucosa - microbiology; Male; Maryland; Middle Aged; Polysaccharides - administration & dosage; Polysaccharides - chemistry; Polysaccharides - metabolism; Prebiotics - analysis; Solubility; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Viscosity; Maryland; OTU; NE; FISH; ME; BHNRC; RM; DGGE; Human; Microflora; Energy; Nutrition
• ISSN: 0022-3166; 1541-6100
• DOI: 10.3945/jn.113.185298

Resistant maltodextrin (RM) is a novel soluble, nonviscous dietary fiber. Its metabolizable energy (ME) and net energy (NE) values derived from nutrient balance studies are unknown, as is the effect of RM on fecal microbiota. A randomized, placebo-controlled, double-blind crossover study was conducted (n = 14 men) to determine the ME and NE of RM and its influence on fecal excretion of macronutrients and microbiota. Participants were assigned to a sequence consisting of 3 treatment periods [24 d each: 0 g/d RM + 50 g/d maltodextrin and 2 amounts of dietary RM (25 g/d RM + 25 g of maltodextrin/d and 50 g/d RM + 0 g/d maltodextrin)] and were provided all the foods they were to consume to maintain their body weight. After an adaptation period, excreta were collected during a 7-d period. After the collection period, 24-h energy expenditure was measured. Fluorescence in situ hybridization, quantitative polymerase chain reaction, and 454 titanium technology–based 16S rRNA sequencing were used to analyze fecal microbiota composition. Fecal amounts of energy (544, 662, 737 kJ/d), nitrogen (1.5, 1.8, 2.1 g/d), RM (0.3, 0.6, 1.2 g/d), and total carbohydrate (11.1, 14.2, 16.2 g/d) increased with increasing dose (0, 25, 50 g) of RM (P < 0.0001). Fat excretion did not differ among treatments. The ME value of RM was 8.2 and 10.4 kJ/g, and the NE value of RM was −8.2 and 2.0 kJ/g for the 25 and 50 g/d RM doses, respectively. Both doses of RM increased fecal wet weight (118, 148, 161 g/d; P < 0.0001) and fecal dry weight (26.5, 32.0, 35.8 g/d; P < 0.0001) compared with the maltodextrin placebo. Total counts of fecal bacteria increased by 12% for the 25 g/d RM dose (P = 0.17) and 18% for the 50 g/d RM dose (P = 0.019). RM intake was associated with statistically significant increases (P < 0.001) in various operational taxonomic units matching closest to ruminococcus, eubacterium, lachnospiraceae, bacteroides, holdemania, and faecalibacterium, implicating RM in their growth in the gut. Our findings provide empirical data important for food labeling regulations related to the energy value of RM and suggest that RM increases fecal bulk by enhancing the excretion of nitrogen and carbohydrate and the growth of specific microbial populations.