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.

Zoonotic hepatitis E, mainly caused by hepatitis E virus (HEV) genotype (gt) 3, is a foodborne disease that has emerged in Europe in recent decades. The main animal reservoir for genotype 3 is domestic pigs. Pig liver and liver derivates are considered the major risk products, and studies focused on the presence of HEV in pig muscles are scarce. The objective of the present study was to evaluate the presence of HEV in different organs and tissues of 45 apparently healthy pigs from nine Spanish slaughterhouses (50% national production) that could enter into the food supply chain. Anti-HEV antibodies were evaluated in serum by an ELISA test. Ten samples from each animal were analyzed for the presence of HEV RNA by reverse transcription realtime PCR (RT-qPCR). The overall seroprevalence obtained was 73.3% (33/45). From the 450 samples analyzed, a total of 26 RT-qPCR positive samples were identified in the liver (7/45), feces (6/45), kidney (5/45), heart (4/45), serum (3/45), and diaphragm (1/45). This is the first report on detection of HEV RNA in kidney and heart samples of naturally infected pigs. HEV RNA detection was negative for rib, bacon, lean ham, and loin samples. These findings indicate that pig meat could be considered as a low risk material for foodborne HEV infection.

In a previous work, we have demonstrated that Minthostachys verticillata essential oil has immunomodulatory effects in vitro on cells from allergic patients. Here we characterized main components of M. verticillata essential oil and also tested if these compounds modulate In vitro and in vivo the immediate-type allergic reaction. Gas chromatography was used to identify main components of the essential oil. Pulegone (63.4 %), menthone (15.9 %), and limonene (2.1 %) were found as main classes. IL-13 levels were evaluated from lymphocytes cultures stimulated with allergen alone or combined with monoterpenes. All compounds stimulated cell proliferation but, interestingly, promoted a reduction of IL-13 values, limonene and the mixture of the three compounds being the most active. β-Hexosaminidase release was determined from basophils to which essential oil or monoterpenes were added. We observed that, whichever combination of monoterpenes was used, β-hexosaminidase release was diminished in all cases. Obtained values were even lower than those of antiallergic drug desloratadine. Essential oil and limonene inhibited mast cell activation and degranulation in the skin when testing passive cutaneous anaphylaxis, limonene being the most active. In conclusion, limonene was the compound that showed the most potent immunomodulatory activity. This fact suggests that it constitutes a promising natural alternative for a novel treatment of allergic diseases.

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