The role of lactate on the immunomodulatory properties of the nonbacterial fraction of kefir

IRAPORDA, C; ROMANIN, D; RUMBO, M; GARROTE, G; ABRAHAM, AG

FOOD RESEARCH INTERNATIONAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2014 vol. 62 p. 247 - 253

0963-9969

The identification of components responsible for the bioactive properties of functional foods is of central interestin the food industry. In particular, fermented dairy products that are of a health benefit to the consumer mayexert those salutary effects through the constituent microorganisms per se and/or through other bioactivecomponents. Kefir is a beverage obtained by the fermentation of milk with kefir grains containing differentlactic- and acetic-acid bacteria plus yeasts. We studied the immunomodulatory capacity of the nonbacterialfraction of kefir through approaches involving biochemistry and cell biology. Lactate, a major microbialmetabolicproduct, was identified as the component responsible for the modulation of certain innate immune epithelialresponse: At the concentrations found in kefir-fermented milk, lactate inhibits the activation of intestinalepithelial cells triggered by interleukin-1β, tumor necrosis factor-α, or flagellin. Lactate treatment furthermoreabrogates NF-κB signaling in the cells, whose action could be responsible for the observed modulation of theinflammatory response. These findings provide a new perspective in the analysis of the biologic properties ofkefir-fermented-milk products.