New insights into the metagenomic link between pre‐treatment method, addition of an inoculum and biomethane yield during anaerobic digestion of water hyacinth (Eichhornia crassipes)

BACKGROUND Water hyacinth (Eichhornia crassipes) is a fast growing water weed that threatens the aquatic ecosystem and human activities, hence control of the plant is essential. One such control approach is to harvest and utilize hyacinth as a substrate for anaerobic digestion (AD). Various factors influence AD performance, including substrate pre‐treatment and microbial community composition, amongst others. This study was aimed at establishing the link between method of substrate pre‐treatment, microbial diversity, inoculum addition and biogas yield during AD of hyacinth. RESULTS The addition of an inoculum resulted in microbial community stability and early biomethane production of up to 0.4 L irrespective of pre‐treatment method. However, cultures that lacked inoculum showed distinct microbial community structure variation in response to pre‐treatment method, and minimal early biomethane production (up to 0.1 L). Biogas produced by cultures lacking inoculum was initially mostly composed of carbon dioxide (up to 100% of total biogas), but as digestion proceeded, an increase in biomethane production was observed (up to 60% of total biogas), which correlated with the shift in microbial community structure and increased microbial diversity. This indicates the presence of biogas‐producing microorganisms associated with the collected hyacinth. Canonical correspondence analysis proved that dynamic changes in microbial community structure and biogas yield were strongly correlative. CONCLUSION This study proves that hyacinth pre‐treatment influences microbial community structure and concomitant biogas yield in the absence of an inoculum. The addition of an inoculum aids in stability of microbial community structure and biogas yield irrespective of method of hyacinth pre‐treatmen

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Not AvailableThe Pasteurella multocida subsp. multocida B:2 serotype causes hemorrhagic septicemia in bubalines with high morbidity and mortality in the Indian subcontinent. We report the draft genome sequence of Pasteurella multocida strain VTCCBAA264 isolated from the small-intestine of a buffalo calf that died of high fever.Not Availabl

Concentrações de vitamina A no leite humano e características socioeconômicas e nutricionais maternas: resultados de estudos brasileiros Vitamin A in human milk and socioeconomic and maternal nutritional factors: some results of Brazilian studies

OBJETIVOS: agregar e discutir os resultados de estudos realizados no Brasil que avaliaram a concentração de vitamina A no leite materno. FONTES DOS DADOS: foram pesquisadas as bases LILACS, Banco de Teses da Capes, SciELO (Scientific Electronic Library), e Plataforma Lattes -seção de produção científica. As palavras-chaves utilizadas foram: gestantes, lactante, concentração de vitamina A no leite humano, Brasil. As buscas foram realizadas em 2006 e atualizadas em março de 2008. Foram incluídos todos os estudos localizados. SÍNTESE DOS DADOS: foram localizados 14 estudos, publicados entre 1988 e 2008, heterogêneos quanto ao tamanho da amostra, fase do leite, período do dia da coleta e método de determinação das concentrações de vitamina A. Foram descritas concentrações médias de vitamina A no leite humano entre 0,62 e 4,50 µmol/L. CONCLUSÕES: não houve consenso sobre a relação entre concentração de vitamina A no leite humano e vitamina A dietética, estado nutricional materno, características obstétricas e demográficas e duração da gestação. Sugere-se que estudos futuros utilizem, amostras de leite maduro, coletadas aleatoriamente ao longo dos diferentes períodos do dia, e a utilização do high performance liquid chromatography - HPLC - como método de determinação de vitamina A.<br>OBJECTIVES: to compile the results of Brazilian studies that investigated the vitamin A content of human milk. SOURCES: the searches were performed at LILACS, Banco de Teses da Capes, SciELO (Scientific Electronic Library), and Plataforma Lattes databases. The search strategy was: pregnant, lactating, human milk vitamin A concentration, Brazil. The searches were done in 2006 and updated in March 2008. SUMMARY OF THE FINDINGS: fourteen studies published between 1988 and 2008 were located. These studies were heterogeneous in terms of sample size, milk phase, time of collection and method for determining vitamin A concentrations. The study outcomes described average vitamin A concentrations in human milk ranging from 0.62 to 4.50 µmol/L. CONCLUSIONS: there was no consensus as to the relationship between the vitamin A content of human milk and a diet with a suitable vitamin A content, maternal nutritional status, maternal obstetric and demographical characteristics and duration of pregnancy. The review indicates that future studies should use casual samples of mature milk, and use high performance liquid chromatography - HPLC - as the laboratory technique in order to quantify vitamin A