The antifungal activity of ginger essential oil (GEO; Zingiber officinale Roscoe) was evaluated against Fusarium verticillioides (Saccardo) Nirenberg. The minimum inhibitory concentration (MIC) of GEO was determined by micro-broth dilution. The effects of GEO on fumonisin and ergosterol production were evaluated at concentrations of 500-5000 μg/mL in liquid medium with a 5mm diameter mycelial disc of F. verticillioides. Gas chromatography-mass spectrometry showed that the predominant components of GEO were α-zingiberene (23.9%) and citral (21.7%). GEO exhibited inhibitory activity, with a MIC of 2500 μg/mL, and 4000 and 5000 μg/mL reduced ergosterol biosynthesis by 57% and 100%, respectively. The inhibitory effect on fumonisin B1 (FB1) and fumonisin B2 (FB2) production was significant at GEO concentrations of 4000 and 2000 μg/mL, respectively. Thus, the inhibition of fungal biomass and fumonisin production was dependent on the concentration of GEO. These results suggest that GEO was able to control the growth of F. verticillioides and subsequent fumonisin production.

The chemical composition of Rosmarinus officinalis L. essential oil (REO) was analysed by gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy. The main compounds of the REO were 1.8 cineole (52.2%), camphor (15.2%) and α-pinene (12.4%). The mycelial growth of Fusarium verticillioides (Sacc.) Nirenberg was reduced significantly by 150 μg/mL of REO. Significant microscopic morphological changes were visualised, such as the rupture of the cell wall and the leakage of cytoplasm at 300 μg/mL of REO. At lower concentrations of REO, the effects on the production of ergosterol and the biomass of mycelium varied, as did the effects on the production of fumonisins, but at ≥300 μg/mL of REO, these processes were significantly inhibited, showing the effectiveness of the REO as an antifungal agent. The results suggested that the REO acts against F. verticillioides by disrupting the cell wall and causing the loss of cellular components, subsequently inhibiting the production of fumonisins and ergosterol.

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.

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Existem critérios e regulamentos para a avaliação da qualidade da água em serviços de unidade de terapia ambulatorial e recomendações específicas para os procedimentos realizados em unidades de terapia intensiva (Uti). Um estudo exploratório foi conduzido em equipamentos de hemodiálise em Uti, em uma cidade do Sul do Brasil. Amostras de água foram coletadas da rede de abastecimento público e pós-osmose reversa associada a dois aparelhos de hemodiálise, entre janeiro e junho de 2011. Espectrometria de emissão óptica com fonte de plasma indutivamente acoplado (iCP oES) foi utilizada para análise de metais em níveis de traços. Análises bacteriológicas foram realizadas para pesquisa de bactérias heterotróficas. Os dados obtidos mostraram que as concentrações dos metais não excederam os limites estabelecidos pela legislação. A análise bacteriológica da água para hemodiálise resultou em contagem inferior a 200 UFC/mL, em todos os meses avaliados, com exceção do mês de fevereiro. os resultados obtidos corroboram o fato de que a manutenção e os cuidados necessários com a água para o tratamento dialítico têm sido efetivos. A prevenção de complicações decorrentes de contaminantes químicos ou microbiológicos na água para hemodiálise em Uti requer uma atenção constante, uma vez que as condições dos pacientes são diferentes daquelas encontradas em atendimento ambulatorial.