Lactic acid bacteria isolation from chicken intestinal content and selection of strains with capacity to capture toxic dietary lectins.

BABOT J.D.; ARGAÑARAZ MARTÍNEZ E.; APELLA M. C.; PEREZ CHAIA A.

Egmond aan Zee

Simposio; TENTH SYMPOSIUM ON LACTIC ACID BACTERIA; 2011

Federation of European Microbiological Societies (FEMS) - The Netherlands Society for Microbiology (NVvM).

The diet components of laying hens and broilers contain secondary products of plant metabolism, lectins among them, which act as a defence mechanism in vegetables. The presence of dietary lectins may impair intestinal epithelia development and enzyme digestive activity in baby chicks with the consequent growth depression. Lactic acid bacteria (LAB) may decrease the cytotoxic effects of lectins on intestine epithelial cells capturing them by interacting with bacterial surface carbohydrates. Hence, the aim of this work was to isolate, identify and select LAB strains with capacity to survive the gastrointestinal transit and capture toxic dietary lectins. In addition, Propionibacterium strains previously isolated from the same niche were assayed. LAB strains were isolated from chicken gastrointestinal tract using HHD, LBS and KF media and identified by 16S rDNA gene sequencing. In order to analyse their ability to grow at 42°C, growth kinetics of the strains isolated in HHD, LBS and KF media were studied in LAPTg + 1% lactose, MRS and LAPTg broths, respectively. Then, the strains were subjected to a simulated gastrointestinal digestion, performed at 42°C. Finally, their facility to capture lectins (DBA, ConA, PHA-P, PNA, UEA-I and WGA) was studied fluorometrically. Eighty one LAB strains were isolated from the gastrointestinal content of laying hens; 58 of these strains grew at 42°C. Viable counts of 14 LAB and 4 propionibacteria strains decreased less than a unit log after the simulated gastrointestinal digestion. Thirteen strains seized at least one lectin, WGA and ConA being caught by most of the strains. In conclusion, 13 LAB strains survived gastrointestinal transit and captured toxic dietary lectins.