Aflatoxin B1 adsorption/desorption dynamics in the presence of Lactobacillus rhamnosus RC007 in a gastrointestinal tract simulated model

FOCHESATO, A; CUELLO, D; POLONI, V.; GALVAGNO, M; DOGI C; CAVAGLIERI L.R.

JOURNAL OF APPLIED MICROBIOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2019

1364-5072

Aims: 1) to determine the aflatoxin B1 (AFB1)adsorption and desorption dynamics in the presence of L. rhamnosus RC007 under simulated transit of AFB1at each gastrointestinal tract (GIT - saliva, stomach and intestine) stage consecutively and then, separately, 2) to study the ability of L. rhamnosus RC007 to biotransform AFB1 as a strategy that complements the adsorption process. Moreover, the most efficient culture media for L. rhamnosus RC007 biomass production was selected and kinetic and productive parameters were determined. Methods and results: theAFB1 adsorption and desorption assay simulating the GIT passage of AFB1 (93.89 ng/g) in presence of L. rhamnosus RC007 (108 CFU/mL) was conducted. Moreover, lactic acid production was determined.Results demonstrated that predominant environmental conditions in salivary solution (SS)induced a low AFB1adsorption, while the transit through the gastric solution (GS) and intestinal solution (IS) allowed high percentages of adsorption and did not generate significant AFB1desorption. The L. rhamnosuscell-free supernatant interacting with AFB1showed high percentages of degradation. Kinetic and productive parameters of L. rhamnosus RC007 growing in MRS culture media supplemented with glucose, molasses and whey, were evaluated. The molasses medium had significantly lower lactic acid levels than whey and glucose ones.Molasses medium obtained kinetic and productive parameters similar to those with glucose but better productive parameters were obtained in a shorter time.Conclusions:The AFB1 adsorption and desorption dynamics in the presence of L. rhamnosus RC007was favoured by gastric and intestinal environment.Significance and impact of study:the knowledge of the adsorption dynamics of AFB1 with a microorganism of interest will allow predicting its behavior at each stage of the GIT, and future encapsulation strategies based on the GIT influence on mycotoxin adsorption could be designed.