Physical Inaccessibility of a Resistant Starch Shifts Mouse Gut Microbiota to Butyrogenic Firmicutes. Issue 7 (27th January 2019)

• Record Type: Journal Article
• Authors: Kaur, Amandeep; Chen, Tingting; Green, Stefan J.; Mutlu, Ece; Martin, Berdine R.; Rumpagaporn, Pinthip; Patterson, John A.; Keshavarzian, Ali; Hamaker, Bruce R.
• Is Part Of: Molecular nutrition & food research. Volume 63:Issue 7(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-01-27
• Subjects: Bacteroidetes -- Firmicutes -- gut microbiota -- resistant starch -- butyrate; Food -- Biotechnology -- Periodicals; Food -- Microbiology -- Periodicals; Nutrition -- Periodicals; Food -- Toxicology -- Periodicals; Nutrition -- Periodicals; Food Microbiology -- Periodicals; Food Technology -- Periodicals; Molecular Biology -- Periodicals; 664.0705
• DOI: 10.1002/mnfr.201801012
• Languages: English
• ISSNs: 1613-4125

Abstract

Abstract : Scope: Resistant starch (RS) is utilized by Gram‐negative Bacteroidetes through a starch utilization system (Sus), which requires physical attachment of the bacteria to the substrate. Gram‐positive Firmicutes, which include butyrate producers, utilize RS by other mechanisms, such as amylosomes and secreted amylases/glucoamylases. It has been previously shown that fabricated RS [alginate‐based starch‐entrapped microspheres (SM)] increases butyrate in in vitro human fecal fermentation and was slow fermenting. It has been hypothesized that in vivo SM would disfavor Bacteroidetes and promote Firmicutes, leading to an increase in butyrate production. Methods and results: A C57BL/6J mouse model is used to test type 2 RS (RS2, raw potato) and SM for SCFAs and fecal microbial community structure. Feeding SM for 2 weeks results in 2.4 times higher mol% butyrate in the mouse distal gut than RS2. SM reduces relative abundance of Bacteroidetes and increases Firmicutes in fecal samples at the end of the 2‐week feeding. This phylum‐level taxonomic shift is not observed in animals fed RS2. Conclusion: Through an approach to understand bacterial requirements related to starch utilization, a designed fiber type favors butyrogenic Firmicutes bacteria and provides higher mol% butyrate in the distal gut with potential benefit as an anti‐inflammatory agent and to improve gut barrier function. Abstract : Mice fed physically inaccessible resistant starch entrapped in microspheres (SM) versus accessible resistant starch type 2 (RS2) show significant increase in Firmicutes/Bacteroidetes ratio (F/B) ratio after 2 weeks of feeding. This coincides with higher mol% butyrate in the distal colon of SM‐fed mice.