Study of a yeast strain isolated from chicken feces as potential probiotic and aflatoxin B1 decontamination.

PIZZOLITTO, R. P.; ARMANDO, M.R.; CAVAGLIERI, L.; DALCERO A. M,; SALVANO M. A.

Tafí del Valle (Tucumán)

Jornada; XXV Jornadas científicas, Asociación de Biología de Tucumán; 2008

Soc. Biología de Tucumán

Aflatoxin B1 (AFB1) is one of the mycotoxins with greater implications on health because of its carcinogenic, teratogenic and mutagenic effects, causing a huge impact on poultry production. An answer to this problem is the use of microorganisms as mycotoxin sequestering agents with potential benefic properties on the host. It would play a role in the AFB1bioavailability and thus, protect the consumer from the adverse effects of this mycotoxins. The aims of this study were 1) to isolate, identify and characterize the beneficial and decontaminant properties of yeast isolated from the gut of chickens. The isolation of yeast was done according Gusils et al. (2002). The identification was performed according to the methodology proposed by Pitt and Hocking (1997). Studies on pH tolerance and survival to the presence of bile salts were performed according to Van Der Aa Kuhl et al. (2004). The autoaggregation and coagreggation tests were carried out according to Roos et al. (1999) and Mastromarino et al. (2002), respectively. The AFB1adsorption ability was conducted according to Good et al. (2007). The isolated strain was identified as Saccharomyces cerevisiae. It was able to tolerate the acidic conditions (pH 2) and the presence of bile salts (0.5%) which indicates its resistance to gastrointestinal transit. The strain showed a high degree of autoaggregation and coaggregation with the studied pathogens (Staphylococcus aureus, Escherichia coli, Enterobacter spp.; Salmonella sp.). The AFB1 decontamination ability showed a good efficiency at both the low as high AFB1 concentrations, revealing a cooperative effect with the increased concentration of AFB1 in the medium. The parameters of efficiency were based on theoretical model of the mechanism involved in the process of adsorption (Bueno et al., 2007). In conclusion, the S. cerevisiae strain isolated from feces, posses potential benefic properties and could be used as AFB1 decontaminant in chicken feed. The autoaggregation is a measure of the ability of microorganisms to make biofilms, which protects them from hostile environmental conditions and allows them to colonize the gastrointestinal treatment. Moreover, the coaggregation shows the antagonist effect against pathogens that affect the host. The excellent yeast ability to adsorb AFB1 would protect the animal for possible intoxication.