Biomarkers of Aflatoxin Exposure and Its Relationship with the Hepatocellular Carcinoma

Jager, Alessandra Vincenzi; Ramalho, Fernando Silva; Zambelli, Leandra Náira; Oliveira, Carlos Augusto Fernandes de

doi:10.5772/22476

Cited by 7 publications

(6 citation statements)

References 54 publications

(41 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The main AFB 1 degradation metabolites include aflatoxicol, aflatoxin B 2 a and aflatoxin D 1 , which are reportedly less toxic [ 15 ]. Moreover, two other modified forms, AFB 1 -8,9-epoxide and AFM 1 -8,9-epoxide, can bind to the DNA and provoke carcinogenic and mutagenic effects [ 25 ]. Hence, it is essential to ensure that AFB 1 is effectively detoxified in less harmful molecules.…”

Section: Introductionmentioning

confidence: 99%

Aspergillus flavus Growth Inhibition and Aflatoxin B1 Decontamination by Streptomyces Isolates and Their Metabolites

Campos-Avelar

Noue

Durand

et al. 2021

Toxins

View full text Add to dashboard Cite

Aflatoxin B1 is a potent carcinogen produced by Aspergillus flavus, mainly during grain storage. As pre-harvest methods are insufficient to avoid mycotoxin presence during storage, diverse curative techniques are being investigated for the inhibition of fungal growth and aflatoxin detoxification. Streptomyces spp. represent an alternative as they are a promising source of detoxifying enzymes. Fifty-nine Streptomyces isolates and a Streptomyces griseoviridis strain from the commercial product Mycostop®, evaluated against Penicillium verrucosum and ochratoxin A during previous work, were screened for their ability to inhibit Aspergillus flavus growth and decrease the aflatoxin amount. The activities of bacterial cells and cell-free extracts (CFEs) from liquid cultures were also evaluated. Fifty-eight isolates were able to inhibit fungal growth during dual culture assays, with a maximal reduction going down to 13% of the control. Aflatoxin-specific production was decreased by all isolates to at least 54% of the control. CFEs were less effective in decreasing fungal growth (down to 40% and 55% for unheated and heated CFEs, respectively) and aflatoxin-specific production, with a few CFEs causing an overproduction of mycotoxins. Nearly all Streptomyces isolates were able to degrade AFB1 when growing in solid and liquid media. A total degradation of AFB1 was achieved by Mycostop® on solid medium, as well as an almost complete degradation by IX20 in liquid medium (6% of the control). CFE maximal degradation went down to 37% of the control for isolate IX09. The search for degradation by-products indicated the presence of a few unknown molecules. The evaluation of residual toxicity of the tested isolates by the SOS chromotest indicated a detoxification of at least 68% of AFB1’s genotoxicity.

show abstract

Section: Introductionmentioning

confidence: 99%

Aspergillus flavus Growth Inhibition and Aflatoxin B1 Decontamination by Streptomyces Isolates and Their Metabolites

Campos-Avelar

Noue

Durand

et al. 2021

Toxins

View full text Add to dashboard Cite

show abstract

“…Após a ingestão oral, a AFB 1 é rapidamente absorvida no trato gastrointestinal e biotransformada primariamente no fígado por enzimas associadas ao citocromo P450 (JAGER et al, 2011). Em todas as espécies animais, o processo de biotransformação ocorre em duas fases: a fase I consiste, principalmente, por reações de hidrólise, redução e oxidação, enquanto que a fase II envolve as reações de conjugação dos produtos da fase I. Os metabólitos resultantes incluem produtos hidroxilados, tais como: AFM 1 e aflatoxina Q 1 , demetilados (aflatoxina P 1 ), hidratados (aflatoxina B 2α ) e um produto de redução por enzimas ciotoplasmáticas (aflatoxicol).…”

Section: Biotransformação E Efeitos Tóxicos Das Aflatoxinasunclassified

“…Biomarcadores medem alterações celulares, biológicas ou moleculares em tecidos biológicos, células ou fluidos, fornecendo informação sobre a doença ou exposição à dada substância (JAGER et al, 2011). Os tipos de biomarcadores mais utilizados em saúde humana e animal são os de exposição, de efeito e de susceptibilidade.…”

Section: Aplicação De Afm 1 E Afb 1 -Lisina Como Biomarcadores Na Avaunclassified

Aflatoxina M1 e Aflatoxina B1-lisina como Biomarcadores de Avaliação da Eficiência de Adsorventes para Aflatoxinas: Artigo de Revisão

Rosim

Oliveira

Corassin

2018

Ens Cien C Biol Agra Saúde

View full text Add to dashboard Cite

A contaminação de alimentos por aflatoxinas, principalmente, a aflatoxina B1 (AFB1) representa um problema mundial para a saúde humana e animal. Uma forma de avaliar a exposição a estes contaminantes é analisando a dieta para verificar a ocorrência destes compostos. Esta metodologia, no entanto, tem limitações devido à variabilidade das aflatoxinas encontradas nos alimentos e às diferenças individuais na toxicocinética dos compostos. Por outro lado, o biomonitoramento de aflatoxinas em fluidos biológicos se utilizando de biomarcadores gera informações mais confiáveis sobre a exposição a estas toxinas nos indivíduos. O uso de adsorventes químicos na ração animal possibilita a detoxificação de aflatoxinas sem produzir efeitos tóxicos nem alterar as propriedades nutricionais. Este trabalho teve por objetivo revisar os dados publicados sobre a eficiência in vitro e in vivo de adsorventes para aflatoxinas, bem como estudos referentes ao uso da aflatoxina M1 (AFM1) e da AFB1-lisina como biomarcadores para avaliar a redução da biodisponibilidade da AFB1 por adsorventes em rações. Trabalhos relevantes publicados nos últimos dez anos (2009-presente) foram selecionados nas bases de dados PubMed, Science Direct e Google Scholar. A determinação de AFM1 no leite e/ou na urina, bem como de AFB1-lisina no soro, indica a biodisponibilidade individual da AFB1 em ensaios para avaliar a eficiência de adsorventes em animais. Deste modo, a utilização destes biomarcadores permite reduzir os custos dos ensaios in vivo, além de proporcionar maior padronização dos experimentos e possibilitar a avaliação da eficiência dos adsorventes em condições de campo. Palavras chave: AFB1. - Adsorventes Minerais. Biomarcadores de Exposição - AFB1-lisina - AFM1 AbstractFood contamination by aflatoxins, mainly aflatoxin B1 (AFB1), is a worldwide concern for human and animal health. A possible way to assess the exposure to these contaminants is through the diet analyses to verify the occurrence of mycotoxins. However, this methodology has important limitations due to the variability of mycotoxins found in the food and the individual differences in the toxicokinetics of the compounds. On the other hand, biomonitoring of aflatoxins in biological fluids using biomarkers generates more reliable information on the exposure to these toxins in individuals. The use of chemical adsorbents in animal feed makes it possible to detoxify mycotoxins without producing toxic effects or altering the nutritional properties. The aim of this study was to revise the available published data on the in vitro and in vivo efficacy of adsorbents for aflatoxins, as well as studies on the use of aflatoxin M1 (AFM1) and AFB1-lysine as biomarkers to evaluate the reduction in the bioavailability of AFB1 by adsorbents in feed. Relevant articles published in the last 10 years (2009-present) were selected in PubMed, Science Direct and Google Scholar. Determination of AFM1 in milk and/or urine, and AFB1-lysine in serum, indicate the individual bioavailability of AFB1 in trials conducted for evaluation of adsorbent’s efficiency in animals. Thus, the use of these biomarkers may reduce the costs of in vivo trials, increase the standardization of experiments, and evaluate the adsorbents’ efficiency under field conditions. Keywords: Aflatoxin B1 – Clays - Exposure Biomarkers - Aflatoxin B1-lysine Aflatoxin M1.

show abstract

“…As a high AFB1 degradation potential is not always linked to the suppression of toxicity, it is crucial to study AFB1 degradation products and their respective toxicity. Among the latter, the only degradation product more toxic than AFB1 is AFB1-8,9-epoxide (carcinogenic form of AFB1), the result of the transformation in humans of AFB1 by cytochrome P450 (Vincenzi et al, 2011).…”

Section: Degradation Productsmentioning

confidence: 99%

Microbial degradation of aflatoxin B1: Current status and future advances

Verheecke‐Vaessen

Liboz

Mathieu

2016

International Journal of Food Microbiology

112

View full text Add to dashboard Cite

Aflatoxin B1 (AFB1) is a natural toxin produced by many food-contaminant fungi and is a threat to human and animal health. This review summarizes current knowledge of the different ways to limit AFB1 in the food chain. We start by introducing current data and reviews available on the prevention of AFB1 occurrence, on AFB1 non-biological decontamination and biological adsorption. We then focus on microbial AFB1-degradation. The latter has already been well studied using living organisms, supernatants or purified enzymes. This review compiles information on the variety of protocols and the efficacy of the different sub-kingdoms or classes of microorganisms or their enzymes. We pay particular attention to publications closest to in vivo applications of microbial AFB1-degradation. In addition, this review also provides a summary of the currently known microbial degradation metabolites of AFB1 and their levels of toxicity, and provides recommendations on the most promising techniques to pursue the aim of minimizing ABF1 in the food supply.

show abstract

Biomarkers of Aflatoxin Exposure and Its Relationship with the Hepatocellular Carcinoma

Cited by 7 publications

References 54 publications

Aspergillus flavus Growth Inhibition and Aflatoxin B1 Decontamination by Streptomyces Isolates and Their Metabolites

Aspergillus flavus Growth Inhibition and Aflatoxin B1 Decontamination by Streptomyces Isolates and Their Metabolites

Aflatoxina M1 e Aflatoxina B1-lisina como Biomarcadores de Avaliação da Eficiência de Adsorventes para Aflatoxinas: Artigo de Revisão

Microbial degradation of aflatoxin B1: Current status and future advances

Contact Info

Product

Resources

About