Limitations of an in vitro model of the poultry digestive tract on the evaluation of the catalytic performance of phytases

J Sci Food Agric. 2021 Apr;101(6):2519-2524. doi: 10.1002/jsfa.10878. Epub 2020 Oct 26.

Abstract

Background: The study aims to investigate the limitation of a poultry digestive tract model developed by Menezes-Blackburn et al. [J Agric Food Chem 63: 6142-6149 (2015)] on the evaluation of the bioefficacy of phytases.

Results: It was confirmed that the in vitro model does not mimic the in vivo situation in the birds sufficiently well to identify the best phytase product under real conditions, or to draw conclusion on the effect of phytate concentration, phytate source or feed composition on the bioefficacy of phytase. Addition of calcium ion (Ca2+ ) up to a concentration of 10 g kg-1 to the feed substrate, for example, did not affect enzymatic phytate dephosphorylation in the in vitro model in contrast to the observation in poultry.

Conclusion: The in vitro approach was shown to be applicable as a complementary tool in the pre-selection of promising phytase candidates, resulting in a reduction in the number of feeding trials in the initial screening phase. © 2020 The Author. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Keywords: in vitro model; phosphate release; phytase; phytate dephosphorylation; poultry digestive tract.

MeSH terms

  • 6-Phytase / chemistry*
  • 6-Phytase / metabolism
  • Animals
  • Calcium / chemistry
  • Calcium / metabolism
  • Catalysis
  • Gastrointestinal Tract / enzymology*
  • Gastrointestinal Tract / metabolism
  • Phosphorylation
  • Phytic Acid / chemistry
  • Phytic Acid / metabolism
  • Poultry / metabolism*

Substances

  • Phytic Acid
  • 6-Phytase
  • Calcium