Saccharomyces cerevisiae strains from animal environment with in vitro aflatoxin B1 binding ability and anti-pathogenic bacterial influence

Abstract

Mycotoxins are metabolites produced by fungi growing on foods or feeds and represent a serious hazard to humans and animals. Concerns related to the negative health impact of aflatoxins have led to the investigation of strategies to prevent, eliminate or reduce the presence of these toxins in contaminated products. Saccharomyces cerevisiae strains are among promising candidates that can be used in animal feed for improving the robustness of animals in the production environment. The aim of this work was to isolate and select S. cerevisiae strains from pig environment with aflatoxin B1 (AFB1) binding ability, able to tolerate gastrointestinal conditions and with some potential beneficial properties to the host. S. cerevisiae strains were isolated from animal feed, faeces and gut and identified by morphological and molecular techniques. AFB1 binding percentages varied among yeast strains according to the AFB1 concentration used. The RC016 strain showed the highest adsorption percentage at the three AFB1 concentrations tested in this work (50, 100 and 500 ng/ml) followed by RC008 strain. All yeast strains were able to survive under gastrointestinal conditions and to strongly adhere to Vero cells. All S. cerevisiae strains showed co-aggregation with pathogenic bacteria (Escherichia coli, Enterobacter cloacae and Salmonella enterica sub sp. enterica). Only RC016 and RC008 strongly inhibited the three pathogens assayed. S. cerevisiae strains RC016 and RC008 are promising microorganisms for inclusion in animal feed.

Recent Trends in Microbiological Decontamination of Aflatoxins in Foodstuffs

“…Addition of 0.05% glucomannanes in the basal diet improved broiler performance [79]. It was demonstrated that yeast strains isolated from environments were animals are raised are able to bind to AFB 1 in saline solution (PBS, pH 7) [67]. These strains presented other properties that were beneficial to the host, such as the inhibition of pathogenic bacteria.…”

“…At the 1 µg/mL concentration, 69.1% AFB 1 was removed; at 5 g/mL, removal rate was 41%; and at 20 µg/mL, 34%. S. cerevisiae strains were isolated from animal feed, feces and intestines, and tested for their ability to tolerate gastrointestinal conditions and remove AFB 1 from a contaminated medium [67]. These researchers observed that all strains isolated were able to survive in gastrointestinal conditions, and that the percentage of toxin removed ranged among SC strains (10…”

“…A 19% reduction in AFB 1 during dough fermentation in bread production was observed [91]. S. cerevisiae B 1 (ng/mL) [67] Aflatoxins -Recent Advances and Future Prospects 82 …”

Study on toxigenic fungi in ruminant feeds under desert conditions with special references to its biological control

“…Saccharomyces cerevisiae strains as biological agents were especially used as post harvest diseases control (Franc es et al, 2006). Yeasts may act as antagonistic microorganisms thereby considerably decreasing the growth of filamentous spoilage fungi and also ochratoxigenic microorganisms, these strains were previously proposed to be used in silage (Armando et al, 2011(Armando et al, , 2012(Armando et al, , 2013. This study aimed to isolation and identification of fungi recoverd from feed of ruminants under desert conditions, detection of toxigenic strains of A. flavus and measurement of its toxins besides, detoxification of feeds using biological control.…”

“…(García-Cela et al, 2012) Control by monitoring for selected mycotoxins in all feed ingredients or final feed independent of quality or origin (Arranz EBurdanpal et al, 2006). Combining feedstuff of normal or high quality with feedstuff of known low cost and quality or high risk of mycotoxin contamination (Armando et al, 2011). Prevention of uptake of mycotoxins by use of feed additives (Liz arraga- Paulín et al, 2013).…”