RESUMO

Cyprinid herpesvirus 3 has a worldwide distribution and presents high mortality rates in species of Cyprinus carpio, causing serious economic loss to the global aquaculture industry. The description of this infection in other ornamental fish species is still limited. For this purpose, 100 ornamental fish from 24 different species were tested by PCR for Cyprinid hespesvirus 3 and the positive samples represented 6% of the tested samples. Phylogenetic reconstruction, based on the Thymidine Kinase gene, revealed the existence of two distinct clades. One clade grouped a Brazilian sample with European and Asian genotypes of CyHV-3 and a second clade, containing only Brazilian sequences described in this study. All of the Brazilian sequences showed identity values greater than 97.7% when compared to each other. This is the first report of the occurrence of Cyprinid herpesvirus 3 in ornamental fish species in Brazil. These results in association with further studies of viral isolation and characterization can help in establishing effective surveillance and disease control program.

Assuntos

RESUMO

The aim of this study is to report the occurrence of Lymphocystivirus in Brazilian ornamental fish. From 25 ornamental fish species submitted for molecular diagnosis, only one sample (Pomacanthus imperator) was positive, and its viral nucleotide sequence obtained clustered with sequences of genotype VII. To our knowledge, this is the first report on the genetic characterization of Lymphocystivirus in Brazil.

Assuntos

RESUMO

Megalocytiviruses have a worldwide distribution, causing serious economic loss to the global aquaculture industry. They also present a threat to ornamental fish trade because megalocytiviral infections have unspecified symptoms, making early diagnosis difficult. In this study, 100 ornamental fish from 24 different species were tested by PCR for megalocytivirus, with a 47% positive rate being identified. Phylogenetic reconstruction, based on the major capsid protein (MCP) gene, clustered all Brazilian samples into a single clade, showing identity values ranging from 99% to 100% when compared to each other. This is the first report of megalocytivirus infection in some ornamental fish species in Brazil.

Assuntos

RESUMO

The Brazilian Official Methodology had established the employment of two culture media for determining molds and yeasts in honey samples, being one containing 2% glucose and other 20%. From 2003 onward, it has been established the use of 2% glucose-containing medium only for this purpose. Variation in glucose concentration into culture media may induce interference on osmotic pressure, which may cause difference on fungi identification and counting results. In this study, 30 samples of honey informally traded in the city of São Paulo were analyzed for determining the occurrence of molds and yeasts through spread plate on potato agar media containing 2% and 20% of glucose. No significant difference in fungicounting (CFU.g -1) was found when the cultures in both media were compared, although higher numbers of molds (CFU.g -1), mainly Penicillium spp, were observed in 2% medium. The 20% glucose-containing medium showed the best performance in detecting yeasts (CFU.g -1). In view of the honey be considered as an adverse environment for mycotoxigenesis, although susceptible to yeast fermentation, the 20% glucose medium should be chosen for performing the honey microbiological quality analyses.

Até o ano de 2003, a Metodologia Oficial Brasileira determinava o uso de dois meios de cultura para executar a análise de bolores e leveduras, um contendo 2% e outro com 20% de glicose; atualmente, recomenda-se apenas o de 2%. Concentrações distintas de glicose implicam em pressões osmóticas diferentes, o que pode influenciar no resultado da quantificação e da identificação dos fungos. No presente trabalho, 30 amostras de mel comercializadas informalmente na cidade de São Paulo foram analisadas visando o isolamento de bolores e leveduras por meio de semeadura em superfície em ágar batata contendo 2% e 20% de glicose. Não houve diferença estatística significante entre as contagens de fungos (CFU.g-1) nos dois tipos de meios, embora tenham sido observados números maiores de bolores (CFU.g -1), especialmente Penicillium spp nas amostras cultivados em meio contendo 2% de glicose. O meio com 20% de glicose apresentou melhor desempenho para detectar leveduras (CFU.g -1). Considerando que o mel é um ambiente muito adverso para a micotoxigênese, mas passível de fermentação pelas leveduras, pode-se inferir que o meio com 20% de glicose seja a melhor alternativa para avaliar a qualidade microbiológica desse produto.

RESUMO

The Brazilian Official Methodology had established the employment of two culture media for determining molds and yeasts in honey samples, being one containing 2% glucose and other 20%. From 2003 onward, it has been established the use of 2% glucose-containing medium only for this purpose. Variation in glucose concentration into culture media may induce interference on osmotic pressure, which may cause difference on fungi identification and counting results. In this study, 30 samples of honey informally traded in the city of São Paulo were analyzed for determining the occurrence of molds and yeasts through spread plate on potato agar media containing 2% and 20% of glucose. No significant difference in fungicounting (CFU.g -1) was found when the cultures in both media were compared, although higher numbers of molds (CFU.g -1), mainly Penicillium spp, were observed in 2% medium. The 20% glucose-containing medium showed the best performance in detecting yeasts (CFU.g -1). In view of the honey be considered as an adverse environment for mycotoxigenesis, although susceptible to yeast fermentation, the 20% glucose medium should be chosen for performing the honey microbiological quality analyses.

Até o ano de 2003, a Metodologia Oficial Brasileira determinava o uso de dois meios de cultura para executar a análise de bolores e leveduras, um contendo 2% e outro com 20% de glicose; atualmente, recomenda-se apenas o de 2%. Concentrações distintas de glicose implicam em pressões osmóticas diferentes, o que pode influenciar no resultado da quantificação e da identificação dos fungos. No presente trabalho, 30 amostras de mel comercializadas informalmente na cidade de São Paulo foram analisadas visando o isolamento de bolores e leveduras por meio de semeadura em superfície em ágar batata contendo 2% e 20% de glicose. Não houve diferença estatística significante entre as contagens de fungos (CFU.g-1) nos dois tipos de meios, embora tenham sido observados números maiores de bolores (CFU.g -1), especialmente Penicillium spp nas amostras cultivados em meio contendo 2% de glicose. O meio com 20% de glicose apresentou melhor desempenho para detectar leveduras (CFU.g -1). Considerando que o mel é um ambiente muito adverso para a micotoxigênese, mas passível de fermentação pelas leveduras, pode-se inferir que o meio com 20% de glicose seja a melhor alternativa para avaliar a qualidade microbiológica desse produto.

RESUMO

Water activity - Aw (Aqualab 3TE - Decagon) and molds and yeasts counting were assessed in 60 honey samples traded on open-air markets, supermarkets and natural products establishments at Western region of São Paulo city. Water activity measures showed a mean value of 0.578, and 0.027 as standard deviation, being 0.489 and 0.661 the minimum and maximum values, respectively. Molds and yeasts counting (performed on culture containing 2 and 20% dextrose potato agar) presented the minimum, median and maximum values of 0.5x1; 0.5x1 e 3.9x102 CFU/g respectively on 2% dextrose agar, and 0.5x1; 0.5x10 e 3.9x102 CFU/g, respectively on 20% dextrose agar. No significant difference in mold/yeast counting on 2 and 20% dextrose agar was evidenced; although high rate of absence of mold and yeast growing was observed onto 2% dextrose agar. In conclusion, 59/60 (98.33%) samples presented low probability for fermenting process, as these honey specimens showed low counts of most and yeast ( 15 CFU/g) and/or Aw ( 0.61). Of 60 samples, only one (1.67%) showed a potential fermenting condition owing to the counting value of >100 CFU/g and Aw >0.61. Further studies should be carried out to investigate the culture medium osmolarity for quantifying and identifying molds and yeasts

Foram analisadas 60 amostras de mel vendidas em feiras-livres, supermercados e casas de produtos naturais da zona oeste do município de São Paulo, para avaliar a atividade de água - Aa (Aqualab 3TE - Decagon) e a contagem de bolores e leveduras (em ágar batata contendo 2 e 20% de dextrose). A Aa apresentou valor médio de 0,578 e desvio padrão de 0,027, valor mínimo de 0,489 e máximo de 0,661. A contagem de bolores e leveduras apresentou valor mínimo, mediano e máximo, respectivamente de: 0,5x1; 0,5x1 e 3,9x102 UFC/g no ágar 2% de dextrose e 0,5x1; 0,5x10 e 3,9x102 UFC/g no ágar 20%. Não houve diferença significativa entre as contagens obtidas nos meios com 2 e 20% de dextrose, porém houve maior número de amostras com ausência de crescimento no meio 2%. Concluiu-se que 59/60 amostras (98,33%) tinham pouca probabilidade de sofrer fermentação por apresentarem baixas contagens ( 15 UFC/g) e/ou Aa ( 0,61); apenas 1/60 (1,67%) amostra apresentou uma condição potencial de fermentação, com contagem >100 UFC/g e Aa >0,61; há necessidade de mais informações sobre a importância da osmolaridade do meio de cultura na quantificação e identificação de bolores e leveduras em mel.