Aflatoxins and fumonisins in conventional and organic corn: a comprehensive review.

This review analyzes the occurrence and co-exposure of aflatoxins and fumonisins in conventional and organic corn, and compares the vulnerability to contamination of both. The risks of fungal contamination in corn are real, mainly by the genera Aspergillus and Fusarium, producers of aflatoxins and fumonisins, respectively. Aflatoxins, especially AFB1, are related to a high incidence of liver cancer, and the International Agency Research of Cancer (IARC) classified them in group 1A 'carcinogenic to humans'. The occurrence in conventional corn is reported in many countries, including at higher levels than those established by legislation. IARC classified fumonisins in group 2B 'possibly carcinogenic to humans' due to their link with incidence of esophageal cancer. However, comparing corn and organic and conventional by-products from different regions, different results are observed. The co-occurrence of both mycotoxins is a worldwide problem; nevertheless, there is little data on the comparison of the co-exposure of these mycotoxins in corn and derivatives between both systems. It was found that the agricultural system is not a decisive factor in the final contamination, indicating the necessity of effective strategies to reduce contamination and co-exposure at levels that do not pose health risks.

Fish feed mycobiota and aflatoxins in round fish tissues.

BACKGROUND: Round fish is one of the most consumed fish in Brazil. Farmed fish feed is based mainly on grains, which are susceptible to contamination by mold and mycotoxins. Aspergillus spp., Penicillium spp. and Fusarium spp. are the major mycotoxins producers. The presence of potentially toxigenic fungi in the diet is a concern due to the possibility of cumulative toxins in fish tissues, becoming a risk to food safety. This study aims to assess the mycobiota of fish feed and the occurrence of aflatoxin residues in round fish tissues. Feed and fish samples were collected from fish farming and fish pay properties. Feed was submitted to mold counting and mold identification. The round fish liver and muscle were submitted to the detection and quantification of aflatoxins B1 , B2 , G1 and G2 by high-performance liquid chromatography. RESULTS: In evaluated feed, mold counts in the samples ranged from 2.0 to 4.7 log colony forming units g-1 and the major genera found were Penicillium (61.5%) and Aspergillus (34.6). Aflatoxin B1 (AFB1 ) was detected in 70% liver samples and 43.3% muscle samples, at levels up to 5.70 and 1.13 µg kg-1 , respectively. CONCLUSION: It is concluded that, although the levels were lower than those recommended by Brazilian legislation, round fish are being exposed to diets naturally contaminated by aflatoxins and are susceptible to toxins accumulation in tissues. Therefore, regulations regarding feed should consider limits for mold and aflatoxin contamination in fish edible tissues should be monitored in order to ensure consumers' safety. © 2021 Society of Chemical Industry.

Correction: Effects of dietary aflatoxin B1 on accumulation and performance in matrinxã fish (Brycon cephalus).

[This corrects the article DOI: 10.1371/journal.pone.0201812.].

Antifungal activity of nanoemulsions encapsulating oregano (Origanum vulgare) essential oil: in vitro study and application in Minas Padrão cheese

ABSTRACT The objective of this study was to evaluate the antifungal activity of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare), both in vitro and after application on Minas Padrão cheese. Nanodispersions were obtained by the phase inversion temperature method. Cladosporium sp., Fusarium sp., and Penicillium sp. genera were isolated from cheese samples and used to evaluate antifungal activity. Minimal inhibitory concentrations of non-encapsulated and encapsulated oregano essential oil were determined, and they were influenced by the encapsulation of the essential oil depending on the type of fungus. The antifungal activity of the nanoencapsulated oregano essential oil in cheese slices showed no evidence of an effect of the MICs, when applied in the matrix. On the other hand, an influence of contact time of the nanoemulsion with the cheese was observed, due to the increase in water activity. It was concluded that nanoencapsulated oregano essential oil presented an inhibitory effect against the three genera of fungi evaluated. If environmental parameters, such as storage temperature and water activity, were controlled, the inhibitory effect of nanoemulsions of oregano oil could possibly be greatly improved, and they could be presented as a potential alternative for the preservation of Minas Padrão cheese against fungal contamination.

Antifungal activity of nanoemulsions encapsulating oregano (Origanum vulgare) essential oil: in vitro study and application in Minas Padrão cheese.

The objective of this study was to evaluate the antifungal activity of nanoemulsions encapsulating essential oil of oregano (Origanum vulgare), both in vitro and after application on Minas Padrão cheese. Nanodispersions were obtained by the phase inversion temperature method. Cladosporium sp., Fusarium sp., and Penicillium sp. genera were isolated from cheese samples and used to evaluate antifungal activity. Minimal inhibitory concentrations of non-encapsulated and encapsulated oregano essential oil were determined, and they were influenced by the encapsulation of the essential oil depending on the type of fungus. The antifungal activity of the nanoencapsulated oregano essential oil in cheese slices showed no evidence of an effect of the MICs, when applied in the matrix. On the other hand, an influence of contact time of the nanoemulsion with the cheese was observed, due to the increase in water activity. It was concluded that nanoencapsulated oregano essential oil presented an inhibitory effect against the three genera of fungi evaluated. If environmental parameters, such as storage temperature and water activity, were controlled, the inhibitory effect of nanoemulsions of oregano oil could possibly be greatly improved, and they could be presented as a potential alternative for the preservation of Minas Padrão cheese against fungal contamination.

Effects of dietary aflatoxin B1 on accumulation and performance in matrinxã fish (Brycon cephalus).

Aflatoxins (AF) can be cumulative in fish tissues and can influence weight, length, feed intake and survival depending on the species. The aim of this work is to measure performance and aflatoxin levels in tissues of matrinxã (Brycon cephalus) fish chronically exposed to aflatoxin. Aflatoxin was incorporated into fish diets at the following levels: Control Feed + 0 µg AFB1 kg-1; A. Feed + 10 µg AFB1 kg-1; B. Feed + 20 µg AFB1 kg-1; C. Feed + 50 µg AFB1 kg-1. It was used one tank per treatment, each one with 150 juvenile fish, and three replicates within each tank were used for sampling, that was carried out monthly over a period of six months. Aflatoxin was quantified by HPLC in fish liver and muscle after clean up using immunoaffinity columns. Performance was evaluated by using weight, length, consumption and survival rate. Muscle and liver aflatoxin levels were below the limit of detection in all control samples. Aflatoxins B2, G1 and G2 were not detected in any tissues. Traces (values between limits of detection and quantification) of AFB1 were observed in liver tissue in treatment A from day 30 through 90, reaching 0.32 µg AFB1 kg-1 at 150 days of exposure. Treatment B presented traces up to day 60 and had, with a maximum level of 0.39 µg AFB1 kg-1 at 150 days of exposure. Treatment C had aflatoxin residues after day 30, with values ranging from 0.17 to 0.61 µg AFB1 kg-1 during exposure. Muscle samples only had traces of AFB1 in all treatments. Fish was affected by exposure to AFB1 with higher values (P<0.05) for weight and length in treatments A, B and C relative to controls. Therefore, results indicate that matrinxã do not accumulate AFB1 residues in edible tissues, but chronic exposure affects the species.

Effect of microencapsulated Jabuticaba (Myrciaria cauliflora) extract on quality and storage stability of mortadella sausage.

The aim of the present study was to add microencapsulated Jabuticaba aqueous extract (MJE) to mortadella as a natural dye and to evaluate its possible antioxidant and antimicrobial activity during refrigeration. Anthocyanins in the extract were quantified and identified. Three treatments of mortadella were prepared: without dye (Control), with cochineal carmine (Carmine) and with the addition of 2% MJE. We determined the chemical composition of mortadella, along with pH, instrumental color, lipid oxidation, microbiological characteristics (Escherichia coli, Staphylococcus aureus, Salmonella, sulphite-reducing Clostridium, aerobic mesophiles, aerobic psychrotrophics and lactic acid bacteria) and sensory acceptance during storage at 4 °C for 56 days. MJE showed high content of anthocyanins, with prevalence of cyanidin-3-glucoside. MJE improved sensory acceptance of texture and flavor of mortadella (P < 0.05), but we observed a slight decrease in color and aroma attributes (P < 0.05). Lipid oxidation of mortadella was not influenced by MJE or cochineal carmine. MJE also displayed a minor effect on physicochemical and microbiological characteristics during storage. As MJE did not alter most of mortadella sausage's evaluated characteristics, it could be used as a natural dye in order to make better use of agro industry waste and to create a meat product enriched with natural antioxidants.

Species identification and antimicrobial susceptibility profile of bacteria causing subclinical mastitis in buffalo / Identificação de espécies e perfil de susceptibilidade antimicrobiano de bactérias causadoras de mastite subclínica em búfalos

Microorganisms causing subclinical mastitis in water buffalo were isolated from 20 buffalo milk samples at four dairy farms located in central region of São Paulo State, Brazil, through testing of somatic cell count (SCC), standard plate count (SPC), biochemical, PCR assays and antimicrobial profile. The SCC showed average of 721,000 cells/mL in the milk, indicating the presence of subclinical mastitis. The overall average for SPC was 1.8 x 104 CFU/mL. The microorganism most frequently isolation according to biochemical tests were: Staphylococcus epidermidis (17%), Staphylococcus aureus (15%), Bacillus spp. (14%), Acinetobacter spp. (12.5%); with intermediate frequency: Pseudomonas aeruginosa (9.5%); Shigella flexneri (7.0%), Streptococcus spp. (5.5%), Corynebacterium spp. (5.0%), Escherichia coli (4.5%), Serratia marcescens (4.0%), Stenotrophomonas maltophilia (4.0%), and low incidence: Klebsiella rhinoscleromatis (0.5%), Klebsiella ozaenae (0.5%), Tatumella ptyseos (0.5%), Enterobacter cloacae (0.5%). The molecular analysis indicated that samples positive by culture method of the genera Staphylococcus, Streptococcus and E. coli were positive by PCR. Para S. aureus and S. epidermidis the highest percentages of observed sensitivity were gentamicin (100%) and vancomycin (100%); for the genus Streptococcus to gentamicin and oxacillin and E. coli to Ampicilin. These findings may help in the control and treatment of subclinical mastitis in buffaloes and contribute to improving the efficiency and quality of the milk produced.(AU)

Microrganismos causadores de mastites subclínicas em búfalas foram isolados desde 20 amostras de leite de búfalos de quatro granjas leiteiras localizadas na região central do Estado de São Paulo, Brasil, através dos testes contagem de células somáticas (CCS), contagem padrão em placas (CPP), provas bioquímicas, reações de PCR e perfil antimicrobiano. A CCS apresentou uma mediana de 721.000 cel/mL no leite, indicando presença de mastite subclínica. A média geral de CPP foi de 1,8x104 UFC/mL. Os microrganismos com maior frequência de isolamento segundo os testes bioquímicos foram: Staphylococcus epidermidis (17%), Staphylococcus aureus (15%), Bacillus spp. (14%), Acinetobacter spp. (12,5%); frequência intermediaria: Pseudomonas aeruginosa (9,5%); Shigella flexneri (7,0%), Streptococcus spp. (5,5%), Corynebacterium spp. (5,0%), Escherichia coli (4,5%), Serratia marcescens (4,0%), Stenotrophomonas maltophilia (4,0%), e baixa incidência: Klebsiella rhinoscleromatis (0,5%), Klebsiella ozaenae (0,5%), Tatumella ptyseos (0,5%), Enterobacter cloacae (0,5%). A análise molecular indicou que as amostras positivas pelo método de cultura dos gêneros Staphylococcus, Streptococcus e Escherichia coli foram positivas por PCR. Para S. aureus e S. epidermidis os maiores percentuais de sensibilidade observados foram gentamicina (100%) e vancomicina (100%); para o gênero Streptococcus à gentamicina e oxacilina e para E. coli à ampicilina. Este resultados podem ajudar no controle e tratamento da mastite subclínica em búfalos e contribuir para melhorar a eficiência e qualidade do leite produzido.(AU)

Determination of aflatoxins in peanut products in the northeast region of São Paulo, Brazil.

The aim of the present study was to determine aflatoxin levels in peanut products traded in the Northeast region of São Paulo, Brazil. To this end, 240 samples of peanut products traded in the cities of Araras, Leme, Pirassununga and Porto Ferreira were collected from June 2006 to May 2007. The samples were analyzed for aflatoxins (AF) B(1), B(2), G(1) and G(2) by high performance liquid chromatography. Results showed 44.2% samples positive for AF at levels of 0.5 to 103.8 microg x kg(-1). Nine of the positive samples (3.7% of the analysed samples) had total aflatoxin concentrations (B(1)+B(2)+G(1)+G(2)) higher than the limit established by Brazilian regulations (20 microg x kg(-1)). Based on the above data, the probable mean daily intake (PDI(M)) of aflatoxins from peanut products in the Northeast region of São Paulo was estimated to be 0.23 ng kg b.w. day(-1). Although this PDI(M) value was relatively low, results indicate that aflatoxin contamination of peanut products may be a public health concern in Brazil, when considering the potential exposure of highly susceptible consumers. For example, it should be emphasized that children are potentially exposed to aflatoxins, since they consume large quantities of peanut candies, and these products had the highest number of samples positive for AFB(1).