Antifungal activity of two Lactobacillus strains with potential probiotic properties

GERBALDO G.; BARBERIS C.; PASCUAL L.; DALCERO A.; BARBERIS L.

FEMS MICROBIOLOGY LETTERS

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 332 p. 27 - 33

0378-1097

Aflatoxin (highly toxic and carcinogenic secondary metabolites produced by fingi) contamination is a serious problem worldwide. Modern agriculture and animal production systems need to use high-quality and mycotoxin-free feed- stuffs. The use of microorganisms to preserve food has gained importance in recent years due to the demand for reduced use of chemical preservatives by consumers. Lactic acid bacteria are known to produce various antimicrobial compounds that are considered to be important in the biopreservation of food and feed. Lactobacillus rhamnosus L60 and Lactobacillus fermentum L23 are pro- ducers of secondary metabolites, such as organic acids, bacteriocins and, in the case of L60, hydrogen peroxide. The antifungal activity of lactobacilli strains was determined by coculture with Aspergillus section Flavi strains by two quali- tative and one quantitative methods. Both L23 and L60 completely inhibited the fungal growth of all aflatoxicogenic strains assayed. Aflatoxin B1 production was reduced 95.7–99.8% with L60 and 27.5–100% with L23. Statistical analysis of the data revealed the influence of L60 and L23 on growth parameters and aflatoxin B1 production. These results are important given that these aflatoxi- cogenic fungi are natural contaminants of feed used for animal production, and could be effectively controlled by Lactobacillus L60 and L23 strains with probiotic properties.