Metataxonomic characterization of the microbial community involved in the production of biogas with microcrystalline cellulose in pilot and laboratory scale.

Biogas, produced in anaerobic digestion, is a sustainable alternative for generating energy from agro-industrial and municipal waste. Information from the microbiota active in the process expands the possibilities for technological innovation. In this study, taxonomic annotations, and functional prediction of the microbial community of the inoculum of two processes were carried out: an industrial unit (pilot-scale urban solid waste plant-IU) and a laboratory-scale reactor fed with swine and cattle waste (LS). The biochemical potential of biogas was obtained using tested inoculum with microcrystalline cellulose, obtaining 682 LN/kgVS (LSC-laboratory scale inoculum and microcrystalline cellulose), and 583 LN/kgVS (IUC-industrial unit inoculum and microcrystalline cellulose), which is equivalent to a recovery of 91.5% of total biogas to LSC. The phyla Synergistota and Firmicutes were more abundant in LS/LSC. In the IU/IUC (treatment of restaurant waste and customs seizures), there was a greater microbiological variety and a predominance of the Bacteroidota, Cloacimonadota, Firmicutes and Caldatribacteriota. The genus Methanosaeta predominated in the process, and it was possible to infer the genes (K01895, K00193 and K00625) related to acetoclastic pathway, as well as endoglucanases that are involved in the metabolism of cellulose (LSC). Terpenoids, polyketides, cofactors, and vitamin metabolism were higher in reactors that received different substrates (IU; IUC). The taxonomic and functional differences revealed the importance of determining the microbiota in the analysis of the potential of an inoculum, combined with the use of microcrystalline cellulose, which can provide optimization information in the production of clean energy.

Seasonal characterization of the prokaryotic microbiota of full-scale anaerobic UASB reactors treating domestic sewage in southern Brazil.

Upflow Anaerobic Sludge Blanket (UASB) reactors are alternatives in the anaerobic treatment of sanitary sewage in different parts of the world; however, in temperate environments, they are subject to strong seasonal influence. Understanding the dynamics of the microbial community in these systems is essential to propose operational alternatives, improve projects and increase the quality of treated effluents. In this study, for one year, high-performance sequencing, associated with bioinformatics tools for taxonomic annotation and functional prediction was used to characterize the microbial community present in the sludge of biodigesters on full-scale, treating domestic sewage at ambient temperature. Among the most representative phyla stood out Desulfobacterota (20.21-28.64%), Proteobacteria (7.48-24.90%), Bacteroidota (10.05-18.37%), Caldisericota (9.49-17.20%), and Halobacterota (3.23-6.55%). By performing a Canonical Correspondence Analysis (CCA), Methanolinea was correlated to the efficiency in removing Chemical Oxygen Demand (COD), Bacteroidetes_VadinHA17 to the production of volatile fatty acids (VFAs), and CI75cm.2.12 at temperature. On the other hand, Desulfovibrio, Spirochaetaceae_uncultured, Methanosaeta, Lentimicrobiaceae_unclassified, and ADurb.Bin063-1 were relevant in shaping the microbial community in a co-occurrence network. Diversity analyses showed greater richness and evenness for the colder seasons, possibly, due to the lesser influence of dominant taxa. Among the principal metabolic functions associated with the community, the metabolism of proteins and amino acids stood out (7.74-8.00%), and the genes related to the synthesis of VFAs presented higher relative abundance for the autumn and winter. Despite the differences in diversity and taxonomic composition, no significant changes were observed in the efficiency of the biodigesters.

Variation of the Prokaryotic and Eukaryotic Communities After Distinct Methods of Thermal Pretreatment of the Inoculum in Hydrogen-Production Reactors from Sugarcane Vinasse.

The aim of this study is to evaluate the effect of different thermal pretreatments of the inoculum on the diversity of the microbial community producing hydrogen from sugarcane vinasse. High-throughput sequencing of the 16S and 18S rRNA genes was performed. The reactor samples were also selected for the isolation of strict anaerobes. Decreased microbial diversity was observed with increasing pretreatment temperatures, with Firmicutes predominating: 90% to 97%. The highest abundance of Staphylococcus (7.9%) was found in pretreatment at 120 °C / 20 min at pH 6. The fungal analysis revealed a high prevalence of Candida (47%), Agaricomycetes, Pezizomycotina and Aspergillus in assays with higher H2 production (90° C / 10 min at pH 6). Three species of Clostridium were isolated: C. bifermentans, C. saccharoperbutylacetonicum and C. saccharobutylicum. The isolates were tested separately and in co-cultures for the production of hydrogen. Hydrogen-producing capacity by co-culture of Clostridium species was increased by 18%. Knowing microorganisms and understanding the interaction between eukaryotes and prokaryotes is essential to obtain strategies for biotransformation of vinasse for the production of bioenergy.

Incidência de doença diarreica aguda em Caxias do Sul, Rio Grande do Sul, Brasil, em uma série histórica de 10 anos / Incidence of acute diarrheal disease in Caxias do Sul, Rio Grande do Sul, Brazil, in a 10-year historical series

Objetivos: Avaliar a incidência de doença diarreica aguda registrada em Caxias do Sul, em um período de 10 anos, investigando suas correlações com a vacinação contra rotavírus, com a precipitação pluviométrica e com o número de internações hospitalares. Métodos: Foi realizado um estudo descritivo dos registros de doença diarreica aguda, disponibilizados pelo setor de Vigilância Epidemiológica da Secretaria Municipal de Saúde de Caxias do Sul. Resultados: Entre 2004 e 2013 foram registrados 61.246 casos de doença diarreica aguda, sendo que os maiores números ocorreram em bairros de baixa renda. Durante o período de avaliação foram identificados cinco surtos epidêmicos de doença diarreica aguda, em meses de verão e inverno. Não foram encontradas relações entre doença diarreica aguda e precipitação pluviométrica. O número de internações hospitalares por doença diarreica aguda em crianças de zero a quatro anos decresceu a partir de 2006, coincidindo com o início do programa de vacinação contra rotavírus na rede pública, enquanto que os óbitos de todas as idades sofreram flutuações durante o período estudado. Conclusões: A avaliação da incidência de doença diarreica aguda, por longo período, mostra que houve flutuações ao longo do tempo no número de registros e de óbitos em Caxias do Sul. Este estudo revelou também uma redução no número de internações devidas a doença diarreica aguda no período que sucedeu à introdução do programa de vacinação contra rotavírus na rede pública de saúde.

Aims: To evaluate the incidence of acute diarrheal disease (ADD) recorded over a 10-year period in Caxias do Sul, southern Brazil, and its correlations with the vaccination against rotavirus, with rainfall, and with the number of hospitalizations. Methods: A descriptive study was conducted, analyzing the ADD records obtained from the Epidemiological Surveillance sector of the Local Health Department of Caxias do Sul. Results: A total of 61,246 cases of ADD were recorded between 2004 and 2013, most of which occurred in low-income neighborhoods. There were five outbreaks of ADD in the summer and winter months during the study period. No correlations were found between ADD and rainfall. The number of children aged between zero and four years hospitalized for ADD decreased from 2006 onwards, when vaccination against rotavirus was implemented in the public health network whereas the number of deaths across all age groups fluctuated during the study period. Conclusions: The assessment of the long-term incidence of ADD showed a fluctuation in the number of cases and deaths in Caxias do Sul. In addition, hospitalizations for ADD decreased after the implementation of rotavirus vaccination in the public health network.

Viability of Cabralea canjerana extracts to control the South American fruit fly, Anastrepha fraterculus.

Several representatives of Meliaceae contain biologically active compounds that are toxic to insects with few negative effects on the environment and humans. Our study evaluated the activity of ethyl acetate and ethanol extracts from the fruit and seeds of Cabralea canjerana (Vellozo) Mart (Sapindales: Meliaceae) on Anastrepha fraterculus (Wiedemann) (Diptera: Tephritidae). Limonoids and triterpenes were detected in fruit and seed extracts. Each extract was added to an artificial diet at three concentrations and tested after 24, 48, and 72 hr of extract application. Ethyl acetate extracts were the most active ones and showed the effect of both dose and time elapses after application on the insects. The highest toxic effect on A. fraterculus adults was from ethyl acetate extracts from fruit, followed by extracts from seeds. These extracts showed antifeedant activities. Extract solutions sprinkled on fruits of Carica papaya (L.) (Brassicales: Caricaceae) caused oviposition repellency and negatively affected the biological development of A. fraterculus. Ethyl acetate extracts highly hampered oviposition, but seed extracts showed lesser oviposition deterrence. The fruit and seed extracts diminished pupal viability. Particularly, the ethyl acetate fruit extract caused malformed adults. The sex ratio was also affected, resulting in female predominance for the fruit extract, while the seed extract showed a dose-dependent effect. Low doses caused male abundance, but at higher concentrations the effect was reversed. These encouraging results showed that the C. canjerana extracts have great potential as new tools to be used in integrated pest management programs to protect fruits against A. fraterculus.