RESUMEN
The aim of this study was to evaluate in vitro the probiotic potential and absorption of Saccharomyces cerevisiae for the aflatoxin B1 in simulated fish intestinal tract conditions. Three yeast strains were used, two from brewery: S. cerevisiae RC1 and S. cerevisiae RC3 and one from a fish farming environment: S. cerevisiae A8L2. The selected yeasts were subjected to the following in vitro tests: homologous inhibition, self-aggregation, co-aggregation, antibacterial activity, gastrointestinal conditions tolerance and adsorption of AFB1. All S. cerevisiae strains showed good capability of self-aggregation and co-aggregation with pathogenic bacteria. All yeast strains were able to survive the gastrointestinal conditions. In acidic conditions, the factors (strain vs. time) had interaction (P=0.0317), resulting in significant variation among the strains tested in the time periods analyzed. It was observed that there was also interaction (P=0.0062) in intestinal conditions, with an increased number of cells in the 12-hour period for all strains tested. In the adsorption test, the A8L2 strain was statistically more effective (P<0.005) for both AFB1 concentrations evaluated in this study (10 and 25ng/mL). Thus, it was observed that the strains of S. cerevisiae have potential probiotic and adsorbent of AFB1.(AU)
Objetivou-se, com esta pesquisa, avaliar in vitro o potencial probiótico e adsorvente de Saccharomyces cerevisiae para aflatoxina B1 em condições simuladas do trato intestinal de peixes. Foram utilizadas três cepas de leveduras, sendo duas provenientes de cervejaria: S. cerevisiae RC1 e S. cerevisiae RC3, e uma de ambiente de piscicultura: S. cerevisiae A8L2. As leveduras selecionadas foram submetidas aos seguintes testes in vitro: inibição homóloga, autoagregação, coagregação, atividade antibacteriana, viabilidade às condições gastrointestinais e adsorção de AFB1. Todas as estirpes de S. cerevisiae mostraram boa capacidade de autoagregação e coagregação com bactérias patogênicas. Todas as estirpes de levedura foram capazes de sobreviver às condições gastrointestinais. Em condições ácidas, os fatores (cepa x tempo) tiveram interação (P=0,0317), resultando em variações significativas entre as cepas testadas nos períodos de tempo analisados. Observou-se que também houve interação (P=0,0062) em condições intestinais, havendo um aumento do número de células no período de 12h para todas as cepas avaliadas. No ensaio de adsorção, a estirpe A8L2 foi a mais eficaz estatisticamente (P<0,005), para as duas concentrações de AFB1 avaliadas neste estudo (10 e 25ng. mL-1). Dessa forma, conclui-se que as cepas de Saccharomyces cerevisiae possuem potencial probiótico e adsorvente de AFB1.(AU)
Asunto(s)
Animales , Saccharomyces cerevisiae , Aflatoxina B1/antagonistas & inhibidores , Probióticos/uso terapéutico , Peces/fisiología , Intestinos/microbiología , Técnicas In Vitro , AdsorciónRESUMEN
The aim of this study was to evaluate in vitro the probiotic potential and absorption of Saccharomyces cerevisiae for the aflatoxin B1 in simulated fish intestinal tract conditions. Three yeast strains were used, two from brewery: S. cerevisiae RC1 and S. cerevisiae RC3 and one from a fish farming environment: S. cerevisiae A8L2. The selected yeasts were subjected to the following in vitro tests: homologous inhibition, self-aggregation, co-aggregation, antibacterial activity, gastrointestinal conditions tolerance and adsorption of AFB1. All S. cerevisiae strains showed good capability of self-aggregation and co-aggregation with pathogenic bacteria. All yeast strains were able to survive the gastrointestinal conditions. In acidic conditions, the factors (strain vs. time) had interaction (P=0.0317), resulting in significant variation among the strains tested in the time periods analyzed. It was observed that there was also interaction (P=0.0062) in intestinal conditions, with an increased number of cells in the 12-hour period for all strains tested. In the adsorption test, the A8L2 strain was statistically more effective (P<0.005) for both AFB1 concentrations evaluated in this study (10 and 25ng/mL). Thus, it was observed that the strains of S. cerevisiae have potential probiotic and adsorbent of AFB1.(AU)
Objetivou-se, com esta pesquisa, avaliar in vitro o potencial probiótico e adsorvente de Saccharomyces cerevisiae para aflatoxina B1 em condições simuladas do trato intestinal de peixes. Foram utilizadas três cepas de leveduras, sendo duas provenientes de cervejaria: S. cerevisiae RC1 e S. cerevisiae RC3, e uma de ambiente de piscicultura: S. cerevisiae A8L2. As leveduras selecionadas foram submetidas aos seguintes testes in vitro: inibição homóloga, autoagregação, coagregação, atividade antibacteriana, viabilidade às condições gastrointestinais e adsorção de AFB1. Todas as estirpes de S. cerevisiae mostraram boa capacidade de autoagregação e coagregação com bactérias patogênicas. Todas as estirpes de levedura foram capazes de sobreviver às condições gastrointestinais. Em condições ácidas, os fatores (cepa x tempo) tiveram interação (P=0,0317), resultando em variações significativas entre as cepas testadas nos períodos de tempo analisados. Observou-se que também houve interação (P=0,0062) em condições intestinais, havendo um aumento do número de células no período de 12h para todas as cepas avaliadas. No ensaio de adsorção, a estirpe A8L2 foi a mais eficaz estatisticamente (P<0,005), para as duas concentrações de AFB1 avaliadas neste estudo (10 e 25ng. mL-1). Dessa forma, conclui-se que as cepas de Saccharomyces cerevisiae possuem potencial probiótico e adsorvente de AFB1.(AU)
Asunto(s)
Animales , Saccharomyces cerevisiae , Aflatoxina B1/antagonistas & inhibidores , Probióticos/uso terapéutico , Peces/fisiología , Intestinos/microbiología , Técnicas In Vitro , AdsorciónRESUMEN
In this study an Iron oxide/carbon nanocomposite from maize straw was prepared and was characterized by XRD, SEM, EDX, FTIR, TG/DTA and Surface area analyzer. The adsorbent was fed to different groups of poultry birds along with aflatoxin B1. Different physiological and blood parameters were monitored in order to study the efficacy of the prepared adsorbent for binding of aflatoxin B1 in the gastrointestinal tract of chickens. It was found that adsorbent at dose of 0.3%/ kg feed was highly effective in detoxifying aflatoxin B1 in gastrointestinal tract of poultry birdswith no harmful effects. The high doses given to groups E and F; 0.4% and 0.5% respectively showed slight variation in tested parameters from group A. No negative symptoms associated with the use of activated carbon as previously reported were observed for the adsorbent under study.(AU)
Asunto(s)
Animales , Aves de Corral/microbiología , Enfermedades de las Aves de Corral/dietoterapia , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/sangre , Pollos , Aflatoxina B1/antagonistas & inhibidoresRESUMEN
In this study an Iron oxide/carbon nanocomposite from maize straw was prepared and was characterized by XRD, SEM, EDX, FTIR, TG/DTA and Surface area analyzer. The adsorbent was fed to different groups of poultry birds along with aflatoxin B1. Different physiological and blood parameters were monitored in order to study the efficacy of the prepared adsorbent for binding of aflatoxin B1 in the gastrointestinal tract of chickens. It was found that adsorbent at dose of 0.3%/ kg feed was highly effective in detoxifying aflatoxin B1 in gastrointestinal tract of poultry birdswith no harmful effects. The high doses given to groups E and F; 0.4% and 0.5% respectively showed slight variation in tested parameters from group A. No negative symptoms associated with the use of activated carbon as previously reported were observed for the adsorbent under study.(AU)
Asunto(s)
Animales , Aves de Corral/microbiología , Enfermedades de las Aves de Corral/dietoterapia , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/sangre , Pollos , Aflatoxina B1/antagonistas & inhibidoresRESUMEN
Aflatoxin B1 (AFB1) and fumonisin B1 (FB1) are mycotoxins that often co-occur in feedstuffs. The ingestion of AFB1 causes aflatoxicosis in humans and animals. Sodium bentonite (NaB), a cheap non-nutritive unselective sequestering agent incorporated in animal diets, can effectively prevent aflatoxicosis. Fumonisins are responsible for equine leukoencephalomalacia and porcine pulmonary oedema, and often have subclinical toxic effects in poultries. Fumonisin B1 and aflatoxin B1 are both strongly adsorbed in vitro on sodium bentonite. Co-adsorption studies, carried out with a weight ratio of FB1 to AFB1 that mimics the natural occurrence (200:1), showed that FB1 greatly decreases the in vitro ability of NaB to adsorb AFB1. The ability of two activated carbons to adsorb FB1 was also investigated. Both carbons showed high affinity for FB1. A complex behaviour of the FB1 adsorption isotherms with pH was observed. In vitro results suggest that under natural contamination levels of AFB1 and FB1, a mixture of activated carbon and sodium bentonite might be potentially useful for prevention of sub-acute aflatoxicosis.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Bentonita/uso terapéutico , Carbón Orgánico/administración & dosificación , Aditivos Alimentarios , Micotoxicosis/veterinaria , Adsorción , Aflatoxina B1/química , Alimentación Animal/análisis , Animales , Bentonita/química , Carbón Orgánico/química , Eucalyptus , Contaminación de Alimentos/análisis , Enfermedades de los Caballos/inducido químicamente , Enfermedades de los Caballos/prevención & control , Caballos , Humanos , Micotoxicosis/prevención & control , Enfermedades de las Aves de Corral/inducido químicamente , Enfermedades de las Aves de Corral/prevención & control , Porcinos , Enfermedades de los Porcinos/inducido químicamente , Enfermedades de los Porcinos/prevención & control , MaderaRESUMEN
The antifungal and antiaflatoxigenic properties of Thymus vulgaris essential oil (TEO) were evaluated upon Aspergillus flavus "in vitro". Suspension containing 10(6) of A. flavus were cultivated with TEO in concentrations ranging from 50 to 500 µg/mL. TEO reached minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 250 µg/mL. Inhibition of ergosterol biosynthesis was detected at a concentration of 100 µg/mL of TEO. Morphological evaluation performed by both light microscopy and scanning electron microscopy showed that antifungal activity of TEO could be detected starting at a concentration of 50 µg/mL and the fungicide effect at a concentration of 250 µg/mL. TEO completely inhibited production of both B1 and B2 aflatoxins (AFB1 and AFB2) at a concentration of 150 µg/mL. This way, fungal biomass development and aflatoxin production were dependent on TEO concentration. Therefore, TEO was capable of controlling the growth of A. flavus and its production of aflatoxins.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Aflatoxinas/antagonistas & inhibidores , Antifúngicos/farmacología , Aspergillus flavus/efectos de los fármacos , Aceites Volátiles/farmacología , Thymus (Planta)/metabolismo , Aflatoxina B1/biosíntesis , Aflatoxinas/biosíntesisRESUMEN
The main objective of this study was to determine if the competitive adsorption of tryptophan (Trp) and aflatoxin B1 (AFB1) could potentially affect the ability of a sodium bentonite (NaB) to prevent aflatoxicosis in monogastric animals. The adsorption of Trp and AFB1 on this adsorbent is fast and could be operating on the same time-scale making competition feasible. In vitro competitive adsorption experiments under simulated gastrointestinal conditions were performed. A high affinity of the clay for Trp and NaB was observed. The effect of an excess of KCl to mimic the ionic strength of the physiological conditions were also investigated. A six-times decrease in the Trp surface excess at saturation was observed. A similar behaviour was previously found for AFB1 adsorption. Taking into account the amount of Trp adsorbed by the clay and the usual adsorbent supplementation level in diets, a decrease in Trp bioavailability is not expected to occur. Tryptophan adsorption isotherms on NaB were 'S'-shaped and were adjusted by the Frumkin-Fowler-Guggenheim model. The reversibility of the adsorption processes was investigated in order to check a potential decrease in the ability of NaB to protect birds against chronic aflatoxicoses. Adsorption processes were completely reversible for Trp, while almost irreversible for AFB1. In spite of the high affinity of the NaB for Trp, probably due to the reversible character of Trp adsorption, no changes in the AFB1 adsorption isotherm were observed when an excess of the amino acid was added to the adsorption medium. As a consequence of the preferential and irreversible AFB1 adsorption and the reversible weak binding of Trp to the NaB, no changes in the aflatoxin sorption ability of the clay are expected to occur in the gastrointestinal tract of birds.
Asunto(s)
Aflatoxina B1/química , Bentonita/química , Carcinógenos Ambientales/química , Quelantes/química , Modelos Químicos , Triptófano/química , Adsorción , Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/metabolismo , Alimentación Animal , Animales , Argentina , Bentonita/metabolismo , Unión Competitiva , Carcinógenos Ambientales/metabolismo , Quelantes/metabolismo , Estudios de Factibilidad , Aditivos Alimentarios/química , Aditivos Alimentarios/metabolismo , Contaminación de Alimentos/prevención & control , Contenido Digestivo , Cinética , Concentración Osmolar , Aves de Corral , Triptófano/metabolismoRESUMEN
Aflatoxin (highly toxic and carcinogenic secondary metabolites produced by fungi) contamination is a serious problem worldwide. Modern agriculture and animal production systems need to use high-quality and mycotoxin-free feedstuffs. 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 producers 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 qualitative and one quantitative methods. Both L23 and L60 completely inhibited the fungal growth of all aflatoxicogenic strains assayed. Aflatoxin B (1) 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 B (1) production. These results are important given that these aflatoxicogenic fungi are natural contaminants of feed used for animal production, and could be effectively controlled by Lactobacillus L60 and L23 strains with probiotic properties.
Asunto(s)
Antifúngicos , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/metabolismo , Lactobacillus , Probióticos , Aflatoxina B1/análisis , Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/biosíntesis , Análisis de Varianza , Pruebas de Sensibilidad MicrobianaRESUMEN
An organic extract from fresh shrimp (Litopenaeus vannamei) was studied for antimutagenic and antiproliferative properties using Salmonella typhimurium tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. Shrimp extract was sequentially fractionated by thin layer chromatography (TLC) and each fraction was tested for antimutagenic and antiproliferative activities. Crude organic extracts obtained from shrimp reduced the number of revertants caused by aflatoxina B(1), showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. These results suggested that the lipid fraction of the tested species contained compounds with chemoprotective properties that reduce the mutagenicity of AFB(1) and proliferation of a cancer cell line.
Asunto(s)
Antimutagênicos/farmacología , Linfoma de Células B/tratamiento farmacológico , Penaeidae , Extractos de Tejidos/farmacología , Aflatoxina B1/antagonistas & inhibidores , Animales , Antimutagênicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cromatografía en Capa Delgada , Relación Dosis-Respuesta a Droga , Lípidos , Linfoma de Células B/patología , Masculino , Ratones , Ratas , Ratas Sprague-Dawley , Salmonella typhimurium/genética , Extractos de Tejidos/administración & dosificaciónRESUMEN
Aflatoxin B(1) (AFB(1)) is a highly toxic and carcinogenic metabolite produced by Aspergillus species on food and agricultural commodities. Inhibitory effects of essential oil of Ageratum conyzoides, on the mycelial growth and aflatoxin B(1) production by Aspergillus flavus were studied. Cultures were incubated in yeast extract-sucrose (YES) broth for days at 25 degrees C at the following different concentrations of the essential oil (from 0.0 to 30mug/mL). The essential oil inhibited fungal growth to different extents depending on the concentration, and completely inhibited aflatoxin production at concentrations above 0.10microg/mL. The analysis of the oil by GC/MS showed that its main components are precocene II (46.35%), precocene I (42.78%), cumarine (5.01%) and Trans-caryophyllene (3.02%). Comparison by transmission electron microscopy of the fungal cells, control and those incubated with different concentrations of essential oil, showed ultra-structural changes which were concentration dependent of the essential oil of A. conyzoides. Such ultra-structural changes were more evident in the endomembrane system, affecting mainly the mitochondria. Degradation was also observed in both surrounding fibrils. The ability to inhibit aflatoxin production as a new biological activity of A.conyzoides L. indicates that it may be considered as a useful tool for a better understanding of the complex pathway of aflatoxin biosynthesis.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Ageratum/química , Aspergillus flavus/efectos de los fármacos , Aceites de Plantas/farmacología , Aflatoxina B1/biosíntesis , Aflatoxina B1/toxicidad , Antifúngicos/química , Antifúngicos/farmacología , Aspergillus flavus/crecimiento & desarrollo , Aspergillus flavus/metabolismo , Aspergillus flavus/ultraestructura , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Microscopía Electrónica de Transmisión , Aceites de Plantas/químicaRESUMEN
Melampodium divaricatum is a member of the Asteraceae and in Brazil is known as false-calendula, its flowers being used in anti-inflammatory preparations, substituting the true calendula or marigold (Calendula officinalis L.). The flower extract was investigated for mutagenic and antimutagenic effect in the Salmonella/microsome assay. The tested extract was not mutagenic in the strains TA100, TA98, TA97a and TA102 and decreased the mutagenicity of aflatoxin B1, benzo(a)pyrene and daunomycin. Chlorophyll and triterpenes were detected in the extract, and they might have contributed to the observed effect. Our data suggest that these medicinal plants possess cancer chemopreventive properties.
Asunto(s)
Antimutagênicos/farmacología , Asteraceae/química , Mutágenos/toxicidad , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/genética , Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/toxicidad , Animales , Antibacterianos/antagonistas & inhibidores , Antibacterianos/toxicidad , Benzo(a)pireno/antagonistas & inhibidores , Benzo(a)pireno/toxicidad , Clorofila/toxicidad , Cromatografía en Capa Delgada , Daño del ADN/efectos de los fármacos , Daunorrubicina/antagonistas & inhibidores , Daunorrubicina/toxicidad , Relación Dosis-Respuesta a Droga , Flores/química , Pruebas de Mutagenicidad , Mutación/efectos de los fármacos , Mutación/genética , Extractos Vegetales/farmacología , Extractos Vegetales/toxicidad , Ratas , Triterpenos/toxicidadRESUMEN
OBJECTIVE: To ratify the effect of traditional "nixtamalización" upon aflatoxin in corn, to identify the residual compound in dough, to evaluate its toxicity, and to verify the effect of acidic treatment on the regeneration of aflatoxin. MATERIAL AND METHODS: Corn with and without aflatoxin was treated separately with lime and heat to obtain two types of dough. Aflatoxin and the residual compound were quantified by high pressure liquid chromatography (HPLC) and toxicity was evaluated in eight day old chicks. RESULTS: "Nixtamalización" destroyed AFBI (96%) and aflatoxicol (70%). The residual compound was identified as AFBI. Experimental animals died by ingestion of 260 microg of AFBI Dough containing residual aflatoxin was not toxic. Acidic treatment did not increase aflatoxin concentration,nor aflatoxicol. CONCLUSIONS: The results support the use of traditional "nixtamalización" as a means to inactivate aflatoxin in corn and that acidic treatment prevents its regeneration in dough.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/toxicidad , Aflatoxinas/antagonistas & inhibidores , Manipulación de Alimentos , Venenos/toxicidad , Zea mays , Aflatoxina B1/análisis , Aflatoxinas/análisis , Concentración de Iones de Hidrógeno , Venenos/análisis , Zea mays/químicaRESUMEN
OBJETIVO: Confirmar el efecto de la nixtamalización tradicional sobre la aflatoxina, identificar el compuesto remanente en masa, evaluar su toxicidad y su regeneración por tratamiento ácido. MATERIAL Y MÉTODOS: Se utilizó maíz, sin y con aflatoxina, y se nixtamalizó. La toxicidad se evaluó en pollos de ocho días de edad. Se aplicó el tratamiento ácido a la masa. La cuantificación de aflatoxinas se realizó por cromatografía líquida de alta resolución (HPLC). RESULTADOS: La nixtamalización destruyó la aflatoxina (96 por ciento) y el aflatoxicol (70 por ciento); el remanente en masa fue aflatoxina B1. El tratamiento ácido in vitro no eleva las concentraciones de ninguna de las dos micotoxinas. Los pollos murieron al ingerir 260 mg de AFB1, y la masa con aflatoxina remanente no fue tóxica. CONCLUSIONES: Los resultados ilustran el beneficio de la nixtamalización tradicional en la inactivación de las aflatoxinas presentes en maíz y en su no reconstitución por efecto del tratamiento ácido.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Aflatoxina B1/toxicidad , Aflatoxinas/antagonistas & inhibidores , Manipulación de Alimentos , Venenos/toxicidad , Zea mays , Aflatoxina B1/análisis , Aflatoxinas/análisis , Concentración de Iones de Hidrógeno , Venenos/análisis , Zea mays/químicaRESUMEN
Sodium bentonite (SB) was evaluated for its ability to reduce the deleterious effects of fumonisin B1 (FB1) and aflatoxin B1 (AFB1) in broiler diets. It was incorporated into the diets (0.3%) containing 2.5 mg/kg AFB1, 200 mg/kg FB1, or a combination of 2.5 mg/kg AFB1 and 200 mg/kg FB1. Aflatoxin B1 significantly diminished body weight gain, whereas FB1 or the combination of FB1 and SB had no effect. Addition of SB in the diets significantly diminished the inhibitory effects of dietary AFB1. Feeding AFB1 alone caused significant increases in the relative weights of most observed organs. Feeding FB1 alone did not alter relative weights of any organs. In the combined diet (AFB1 plus FB1) relative weights of the liver, kidney, gizzard, and spleen were increased. Addition of SB to the diet containing AFB1 diminished the relative weights of liver, kidney, and spleen. Addition of SB to diets containing AFB1 and FB1 only decreased liver weights. In relation to the control, lower serum levels of total protein, albumin, and globulins were observed for all AFB, containing diets without SB addition, whereas all other treatments were not altered. Livers of birds fed diets containing AFB1 and a combination of AFB1 and FB1 were enlarged, yellowish, friable, and had rounded borders. The histopathology of them, stained with hematoxylin and eosin, showed multifocal and varied cytoplasmatic vacuolization with perilobular location. Incorporation of SB reduced the incidence and severity of the hepatic histopathology changes associated with aflatoxicosis.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Bentonita/administración & dosificación , Pollos , Dieta , Contaminación de Alimentos , Fumonisinas/antagonistas & inhibidores , Aflatoxina B1/farmacocinética , Aflatoxina B1/toxicidad , Alimentación Animal , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas , Fumonisinas/farmacocinética , Fumonisinas/toxicidad , Absorción Intestinal/efectos de los fármacos , Hígado/patología , Hepatopatías/prevención & control , Hepatopatías/veterinaria , Tamaño de los Órganos/efectos de los fármacos , Enfermedades de las Aves de Corral/inducido químicamente , Enfermedades de las Aves de Corral/patología , Enfermedades de las Aves de Corral/prevención & controlRESUMEN
Organic extracts from fresh and smoked yellowtail fish (Seriola lalandi), lisa fish (Mugil cephalus) and cazon fish (Mustelus lunulatus) were tested for mutagenicity using Ames Salmonella tester strains TA98 and TA100 with metabolic activation (S9). Also, the antimutagenicity of the organic extract from yellowtail fish was tested against aflatoxin B1 (AFB1). Yellowtail fish extract was sequentially fractionated by thin-layer chromatography (TLC) and each fraction was also tested for antimutagenicity. None of the fresh species showed mutagenicity. Extract from smoked yellowtail showed the highest mutagenic potential among the smoked species tested. Organic extract from fresh yellowtail reduced the number of revertants caused by AFB1 showing a dose response type of relationship. Sequential TLC fractionation of the antimutagenic extract produced four antimutagenic fractions from fresh yellowtail fish. These results that the lipidic fraction of the species tested contains at least four compounds with chemoprotective properties that reduce the mutagenicity of AFB1.
Asunto(s)
Antimutagênicos/aislamiento & purificación , Productos Pesqueros/análisis , Lípidos , Pruebas de Mutagenicidad , Extractos de Tejidos/toxicidad , Aflatoxina B1/antagonistas & inhibidores , Animales , Antimutagênicos/farmacología , Fraccionamiento Químico , Cromatografía en Capa Delgada , Elasmobranquios , Peces , Manipulación de Alimentos , Calor , Perciformes , HumoRESUMEN
Polyphenols with antimutagenic and anticarcinogenic properties are present in fruits, vegetables and legumes. In this study, the Salmonella typhimurium tester strains TA98 and TA100 were used in the microsuspension assay to examine the antimutagenic effect of phenolic compounds extracted from the common bean (Phaseolus vulgaris) against mutagenicity induced by aflatoxin B1 (AFB1). A dose-response curve was constructed for AFB1; from which a level of 40 ng AFB1/tube was selected for all antimutagenicity assays. The AFB1 and phenolic extract (PE) were not toxic to the bacteria at concentrations tested. In the case of PE, results were similar to the number of spontaneous revertants for TA98 and TA100. The inhibitory effect of PE against AFB1 mutagenicity was dose-dependent at the lower concentrations tested (2.5, 5, 10, 12.5, 15 and 25 microgram-equivalent (+)-catechin/tube for TA98; 0.5, 1, 1.5, 2.5, 5, 10 and 25 microgram-equivalent (+)-catechin/ tube for TA100). Further, a two-stage incubation procedure was used to investigate the potential interaction between PE and AFB1. The greatest inhibitory effect of the PE on AFB1 mutagenicity occurred when PE and AFB1 were incubated together. When the bacteria were first incubated with PE followed by a second incubation with AFB1, lower inhibition was observed. Lower inhibition was also observed when the bacteria were first incubated with AFB1 followed by a second incubation with PE. The results suggest that the mechanism of inhibition could involve the formation of a chemical complex between of PE and AFB1.
Asunto(s)
Aflatoxina B1/antagonistas & inhibidores , Antimutagênicos/farmacología , Fabaceae/química , Fenoles/farmacología , Aflatoxina B1/farmacología , Animales , Relación Dosis-Respuesta a Droga , Humanos , Mutagénesis/efectos de los fármacos , Pruebas de Mutagenicidad/métodos , Fenoles/análisis , Ratas , Ratas Sprague-DawleyRESUMEN
N-acetylcysteine (NAC) has been used safely in humans and in other mammals as an antidote against several toxic and carcinogenic agents, including aflatoxin B1 (AFB1). The aim of this study was to evaluate the capability of dietary supplementation with NAC to ameliorate the effects of subacute intoxication with AFB1 in broiler chickens. One hundred twenty male Hubbard 1-d-old chickens were allocated into one of four dietary treatments: 1) control group without treatment, 2) purified AFB1 added to diet (3 mg/kg of feed) for 21 d, 3) NAC (800 mg/kg BW, daily), or 4) AFB1 plus NAC at the same doses as Groups 2 and 3. Broilers treated with AFB1 plus NAC were shown to be partially protected against deleterious effects on BW (57.8%), daily weight gain (49.1%), feed conversion index (21.4%), plasma and hepatic total protein concentration (45.2, 66.7%), plasma alanine aminotransferase (67.4%), hepatic glutathione-S-transferase (18.8%), and reduced glutathione liver concentration (75.0%). In addition, they showed less intense liver fading, friable texture, and microvesicular steatosis. In the kidney, thickening of glomerular basement membrane was also less severe in NAC+AFB1-treated chickens than in AFB1-treated chickens. Our results suggest that NAC provided protection against negative effects on performance, liver and renal damage, and biochemical alterations induced by AFB1 in broiler chickens. Effects of NAC alone on chick performance were also evaluated. Addition of NAC to diet (800 mg/kg BW) did not negatively affect feed consumption, conversion index, or serum chemistry and did not induce structural changes in the liver or kidney.
Asunto(s)
Acetilcisteína/farmacología , Aflatoxina B1/antagonistas & inhibidores , Pollos , Depuradores de Radicales Libres/farmacología , Enfermedades de las Aves de Corral/prevención & control , Aflatoxina B1/toxicidad , Alanina Transaminasa/sangre , Alanina Transaminasa/efectos de los fármacos , Alimentación Animal , Animales , Aspartato Aminotransferasas/sangre , Aspartato Aminotransferasas/efectos de los fármacos , Proteínas Sanguíneas/efectos de los fármacos , Proteínas Sanguíneas/metabolismo , Peso Corporal/efectos de los fármacos , Enfermedad Hepática Inducida por Sustancias y Drogas , Glutatión/efectos de los fármacos , Glutatión/metabolismo , Glutatión Transferasa/efectos de los fármacos , Glutatión Transferasa/metabolismo , Riñón/efectos de los fármacos , Riñón/patología , Enfermedades Renales/inducido químicamente , Enfermedades Renales/veterinaria , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Hepatopatías/veterinaria , Masculino , Enfermedades de las Aves de Corral/inducido químicamente , Distribución Aleatoria , Resultado del TratamientoRESUMEN
Aflatoxin B1 (AFB1) is a major contaminant in different agricultural products including maize. In an attempt to reduce this problem and the hazards to human health, an AFB1 inactivating system with ammonia has been developed. In this work we evaluated the efficiency of the system in mice using micronucleus (MN) and sister chromatid exchange (SCE) analysis. Four groups of animals were fed during 8 weeks with a special diet mainly composed of maize: (1) uncontaminated; (2) uncontaminated/inactivated; (3) contaminated/inactivated; and (4) contaminated. We evaluated MN at weekly intervals in peripheral blood, and in weeks 4 and 8 SCE frequencies were quantified in bone marrow cells. The results showed that animals fed with AFB1 contaminated/inactivated maize had a 45% lower level of induced cytogenetic damage than those animals fed with AFB1 contaminated, but not inactivated maize. A residual amount of AFB1 after the inactivating treatment and the reconversion back to AFB1 in the organism may account for the remaining increased levels of SCE and MN.