RESUMO
The presence of contaminants such as aflatoxins (AFs) in dairy products constitutes a serious risk to the health of consumers, especially children who are most sensitive to the adverse effects of AFs. The presence of Aflatoxin M1 (AFM1) in milk is a public health problem since dairy products are massively consumed worldwide. The aim of the present work was to select microorganisms capable of reducing AFM1 entry into the food chain through adsorption/degradation strategies. Moreover, the toxicity of AFM1 degradation products was evaluated. All tested strains had the capacity to adsorb 19%-61% AFM1 in milk. These strains also had the ability to degrade AFM1 into metabolites less toxic than the original toxin. Moreover, this is the first study to report harmless and probiotic Pediococcus pentosaceus and Kluveromyces marxianus have the ability to adsorb and degrade AFM1 to less toxic metabolites in milk.
Assuntos
Aflatoxina M1/metabolismo , Inativação Metabólica , Leite/microbiologia , Probióticos/farmacologia , Adsorção , Aflatoxina M1/toxicidade , Animais , Artemia/efeitos dos fármacos , Contaminação de Alimentos , Kluyveromyces/metabolismo , Pediococcus pentosaceus/metabolismoRESUMO
The aim of this study was to evaluate the efficacy of autochthonous Pichia kudriavzevii as a novel bioadsorbent for aflatoxin B1 (AFB1). The selection of this yeast was based on the AFB1 adsorption capacity previously demonstrated in vitro (Magnoli et al. 2016). One-day-old Cobb broilers (n = 160) were randomly assigned to four dietary treatments (T1: basal diet (B); T2: B + 0.1% yeast; T3: B + AFB1, 100 µg/kg; T4: B + 0.1% yeast + AFB1, 100 µg/kg). Performance parameters (average daily weight gain body, average daily consumption, feed conversion ratio, carcass weight, and dead weight), biochemical parameters (albumin, globulin, and albumin/globulin), liver pathological changes, and AFB1 residual levels in the liver and excreta were evaluated. Significant differences (P < 0.05) in performance parameters were observed among treatments and controls: T3 group showed the lowest average daily body weight gain value while in T4 group, the value of this parameter increased significantly (P < 0.05). T3 and T4 groups showed the lowest and highest values for average daily feed consumption, respectively. The feed conversion ratio (FC) showed no significant differences among treatments. T3 group showed the lowest dead weight and carcass weight compared with T1 group. The biochemical parameters showed no significant differences among treatments. T3 group showed macroscopic and microscopic liver changes compared to the control. Aflatoxin B1 levels (µg/g) were detected in broiler livers and showed significant differences among treatments (P < 0.05). In conclusion, native P. kudriavzevii incorporation (0.1%) in broiler diets containing AFB1 was shown to be effective in ameliorating the adverse effects of AFB1 on production.
Assuntos
Aflatoxina B1/efeitos adversos , Galinhas , Suplementos Nutricionais , Pichia , Doenças das Aves Domésticas/prevenção & controle , Ração Animal/análise , Animais , Dieta/veterinária , Fígado/metabolismo , Masculino , Doenças das Aves Domésticas/patologia , Distribuição AleatóriaRESUMO
AIMS: To acquire data on the safety-in-use of the probiotic Saccharomyces cerevisiae RC016 and test its ability to reduce genotoxicity caused by dietary aflatoxins (AFs). METHODS AND RESULTS: The probiotic was orally administered to Wistar rats. Six groups (n = 6) were arranged: feed and probiotic controls, two levels of AFs-contaminated feed and two treatments including both the probiotic and the toxin. Genotoxiciy and cytotoxicity were evaluated with the bone marrow micronuclei assay and the comet assay and internal organs were macroscopically and microscopically examined. The tested S. cerevisiae strain did not cause genotoxicity or cytotoxicity in vivo, and it was able to attenuate AFs-caused genotoxicity. Saccharomyces cerevisiae RC016 did not cause any impairment on the rats' health and it showed no negative impact on the weight gain. Moreover, RC016 improved zootechnical parameters in AFs-treated animals. The beneficial effects were likely to be caused by adsorption of AFs to the yeast cell wall in the intestine and the consequent reduction in the toxin's bioavailability. CONCLUSIONS: The dietary administration of RC016 does not induce genotoxicity or cytotoxicity to rats. SIGNIFICANCE AND IMPACT OF THE STUDY: Incorporation of RC016 in the formulation of feed additives increases animal productivity. Similar effects may even occur in human food applications.
Assuntos
Probióticos/toxicidade , Saccharomyces cerevisiae , Administração Oral , Aflatoxinas/toxicidade , Ração Animal , Animais , Dano ao DNA , Masculino , Ratos , Ratos Wistar , Testes de Toxicidade SubcrônicaRESUMO
AIMS: To evaluate mycobiota and aflatoxins B(1) (AFB(1)), B(2) (AFB(2)), G(1) (AFG(1)), G(2) (AFG(2)) and fumonisin B(1) (FB(1)) contamination in different malted barley types and brands and brewer's grain collected from a major Argentinean brewery. METHODS AND RESULTS: Total fungal counts were performed using the plate count method. Aflatoxin B(1), AFB(2), AFG(1), AFG(2) and Zearalenone (ZEA) analyses were performed by thin-layer chromatography (TLC). Fumonisin B(1) was determined by HPLC. Eighty-three percentage of the malted barley (100% M1, 50% M2 and 100% M3) and 61% of brewer's grain samples had a count >1 × 10(4) CFU g(-1). Yeasts were isolated from all malt and brewer's grain samples. Genera containing some of the most important mycotoxin producer species--Fusarium ssp., Aspergillus ssp., Penicillium ssp. and Alternaria ssp.--were isolated from the analysed samples, along with other environmental saprophytic fungi such as Geotrichum ssp., Mucorales and Cladosporium ssp. All samples were contaminated with 104-145 µg kg(-1) FB(1). Eighteen per cent of brewer's grain samples were contaminated with 19-44.52 µg kg(-1) AFB(1). Aflatoxin B(2), AFG(1), AFG(2) and ZEA were not detected in any of the analysed samples. CONCLUSIONS: Fungal and mycotoxin contamination in malt and brewer's grain is an actual risk for animal and human health. SIGNIFICANCE AND IMPACT OF THE STUDY: This study may be useful for assessing the risk of mycotoxins in Argentinean beers and especially in animal feeds.
Assuntos
Cerveja/microbiologia , Contaminação de Alimentos/análise , Hordeum/microbiologia , Micotoxinas/análise , Ração Animal/microbiologia , Cerveja/análise , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Contagem de Colônia Microbiana , Indústria Alimentícia , Fungos/classificação , Fungos/isolamento & purificação , HumanosRESUMO
Mycotoxin contamination of animal feeds represents a hazard to human and animal health due to potential transmission to meat and milk. Barley by-products are alternative feeding supplies for animal production. The aims of this assay were to study the mycobiota of feedstuffs and finished swine feed, to determine the ability of Aspergillus and Penicillium isolates to produce ochratoxin A (OTA) and to evaluate OTA occurrence in these substrates. Corn, brewers' grains and finished swine feed samples were collected from different factories. Fungal counts were higher than 2.8x10(4)CFU g(-1). Fusarium, Aspergillus and Penicillium genera were isolated at high levels. A 23.7% of the isolates produced 9-116 microg kg(-1) of OTA in vitro. Corn samples (44%) were contaminated with 42-224 microg kg(-1) of OTA. Finished feed (31%) and brewers' grains samples (13%) were contaminated with 36-120 microg kg(-1) and 28-139 microg kg(-1) of OTA, respectively. This is the first scientific report on contamination by OTA-producer molds and OTA in swine feedstuffs from Brazil. The presence of OTA in raw materials and finished feed requires periodic monitoring to prevent mycotoxicoses in animal production, reduce economic losses and minimize hazards to human health.
Assuntos
Ração Animal/análise , Ração Animal/microbiologia , Ocratoxinas/química , Suínos , Animais , Aspergillus/metabolismo , Brasil , Ocratoxinas/metabolismo , Penicillium/metabolismo , Água/químicaRESUMO
AIMS: To evaluate the mycobiota and natural levels of aflatoxins, fumonisins and zearalenone present in compound feed and home-corn grains intended for fattening pigs. METHODS AND RESULTS: Total fungi, Fusarium and Aspergillus species occurrence were examined. Aflatoxins and zearalenone were detected by thin-layer chromatography and fumonisins by high-pressure liquid chromatography. Fungal counts were generally higher than 1 x 10(5) colony forming units (CFU) ml(-1). Aspergillus flavus, Aspergillus parasiticus and Fusarium verticillioides were the most prevalent species. FB(1) and FB(2) were detected in all feed and corn samples. Aflatoxin B(1) was detected in 33.33% of initial and growing feed and in 44.44% of final feed samples. It was not detected in corn samples. All feed and corn samples were negative for AFB(2), AFG(1), AFG(2) and ZEA presence during all growing stages tested. CONCLUSIONS: Fungal counts at all growing periods exceeded the levels proposed as feed hygienic quality limits. Aflatoxin levels in all feeds and fumonisin levels in many samples were higher than the established regulations. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of mycotoxins indicates the existence of contamination. This fact requires periodic monitoring to prevent the occurrence of mycotoxicosis in animal production, to reduce the economic losses and to minimize hazards to human health.
Assuntos
Ração Animal/microbiologia , Aspergillus/isolamento & purificação , Fusarium/isolamento & purificação , Micotoxinas/análise , Aflatoxinas/análise , Ração Animal/análise , Animais , Argentina , Aspergillus/classificação , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Grão Comestível/microbiologia , Contaminação de Alimentos/análise , Fumonisinas/análise , Fusarium/classificação , Técnicas de Tipagem Micológica , Células-Tronco , Suínos , Zearalenona/análiseRESUMO
AIM: To determine fungal genera, Aspergillus and Fusarium species and aflatoxin B(1) (AFB(1)), zearalenone (ZEA), deoxynivalenol (DON), fumonisin B(1) (FB(1)) contamination from pre- and postfermented corn silage produced in the most important region of Argentina where silage practice is developed. METHODS AND RESULTS: Sampling of corn silos was performed manually through silos in transects at three levels: upper, middle and low sections. AFB(1) and FB(1) were quantified by high-performance liquid chromatography, zearalenone by enzyme-linked immunosorbent assay and DON by gas chromatography. Over 90% of the samples showed counts higher than 1 x 10(4) CFU g(-1). Aspergillus flavus and Fusarium verticillioides were the prevalent species. Some tested samples were contaminated with AFB(1), ZEA, DON and FB(1). CONCLUSIONS: This study demonstrates the presence of fungi and AFB(1), ZEA, DON and FB(1) contamination in corn silage in Argentina. SIGNIFICANCE AND IMPACT OF THE STUDY: This manuscript makes a contribution to the knowledge of mycotoxins in Argentinean silage in particular because the environmental conditions in this country differ from those of most reports. The comparison of pre- and postfermentation silage is also outstanding. Therefore, information on fungi and mycotoxins present in silage--an increasingly popular commodity--is useful to estimate potential risk for animal and human health.