Fermentation of resistant starches: influence of in vitro models on colon carcinogenesis

Nutr Cancer. 2007;58(1):85-92. doi: 10.1080/01635580701308232.

Abstract

Resistant starch type 2 (RS2) and type 3 (RS3) containing preparations were digested using a batch (a) and a dynamic in vitro model (b). Furthermore, in vivo obtained indigestible fractions from ileostomy patients were used (c). Subsequently these samples were fermented with human feces with a batch and a dynamic in vitro method. The fermentation supernatants were used to treat CACO2 cells. Cytotoxicity, anti-genotoxicity against hydrogen peroxide (comet assay) and the effect on barrier function measured by trans-epithelial electrical resistance were determined. Dynamically fermented samples led to high cytotoxic activity, probably due to additional compounds added during in vitro fermentation. As a consequence only batch fermented samples were investigated further. Batch fermentation of RS resulted in an anti-genotoxic activity ranging from 9-30% decrease in DNA damage for all the samples, except for RS2-b. It is assumed that the changes in RS2 structures due to dynamic digestion resulted in a different fermentation profile not leading to any anti-genotoxic effect. Additionally, in vitro batch fermentation of RS caused an improvement in integrity across the intestinal barrier by approximately 22% for all the samples. We have demonstrated that batch in vitro fermentation of RS2 and RS3 preparations differently pre-digested are capable of inhibiting the initiation and promotion stage in colon carcinogenesis in vitro.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / metabolism*
  • Caco-2 Cells
  • Colonic Neoplasms / prevention & control*
  • Comet Assay
  • DNA Damage / drug effects
  • Digestion*
  • Fatty Acids, Volatile / analysis
  • Fatty Acids, Volatile / metabolism*
  • Feces / chemistry
  • Feces / microbiology
  • Fermentation*
  • Humans
  • Hydrogen Peroxide / toxicity
  • Hydrogen-Ion Concentration
  • Starch / metabolism*
  • Starch / pharmacology
  • Time Factors

Substances

  • Fatty Acids, Volatile
  • Starch
  • Hydrogen Peroxide