Analysis of petroleum biodegradation by a bacterial consortium isolated from worms of the polychaeta class (Annelida): Implications for NPK fertilizer supplementation.

Degradation of petroleum hydrocarbons using bacterial consortia may be a means of optimizing bioremediation techniques. In this study, bacterial strains were isolated from the digestive tract of polychaete worms and evaluated concerning the potential of the bacteria to degrade petroleum compounds (Acinetobacter sp., Bacillus sp., Pantoea sp. and Enterobacter sp.). The strains were separately screened regarding their potential to degrade oil after 24 h. The main experiment was carried out for 30 days with the addition of nitrogen, phosphorus and potassium (NPK) after 15 days (Bact-NPK15) and 28 days (Bact-NPK28) and without NPK (Bact). The Bact treatment biomass remained stable until the 20th day of the experiment. C13-C40 n-alkanes were degraded with all treatments in the following order: Bact>Bact-NPK28>Bact-NPK15. Significant differences were observed between the controls and all treatments (p = 0.00031). Measurement of polycyclic aromatic hydrocarbons (PAHs) indicates a lower contribution of these compounds in the Bact-NPK28 treatment, although no significant difference between groups was observed. Bact-NPK28 was able to remove 40% of naphthalene, while Bact-NPK15 removed 20%; this effect was not observed in Bact. Higher hopane degradation levels were observed in Bact and, to a lesser extent, in Bact-NPK28. NPK application for 28 days mainly favored PAH degradation. The evaluated consortium thus exhibits potential in the bioremediation of petroleum-contaminated areas.

Integrated assessment of mangrove sediments in the Camamu Bay (Bahia, Brazil).

Camamu Bay, an Environmentally Protected Area, may be affected by the pressures of tourism and oil exploration in the adjacent continental platform. The current quality of the mangrove sediments was evaluated by porewater bioassays using embryos of Crassostrea rhizophorae and by an analysis of benthic macrofauna and its relationships with organic compounds, trace metals and bioavailability. Porewater toxicity varied from low to moderate in the majority of the samples, and polychaetes dominated the benthos. The Grande Island sampling station (Station 1) presented more sandy sediments, differentiated macrobenthic assemblages and the highest metal concentrations in relation to other stations and guideline values, and it was the only station that indicated a possible bioavailability of metals. The origin of the metals (mainly barium) is most likely associated with the barite ore deposits located in the Grande and Pequena islands. These results may be useful for future assessment of the impact of oil exploration in the coastal region.

Increased capture of Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) by removing one ADULTRAP component.

INTRODUCTION: Aedes aegypti is the main vector responsible for the transmission of numerous arboviruses. Adultrap® has been developed to catch these insects. METHODS: We tested the effectiveness of capturing adults with and without one of the components of Adultrap®. RESULTS: The mean number of insects caught by the original trap was 1.25 (standard deviation = 1.28), while the average obtained with the modified trap was 8.88 (standard deviation = 3.44). The medians were statistically different (p = 0.001) according to the Mann-Whitney test. CONCLUSIONS: The modification of Adultrap® increased the average catch of Ae. aegypti by up to seven times.

Increased capture of Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae) by removing one ADULTRAP component

Abstract INTRODUCTION: Aedes aegypti is the main vector responsible for the transmission of numerous arboviruses. Adultrap® has been developed to catch these insects. METHODS: We tested the effectiveness of capturing adults with and without one of the components of Adultrap®. RESULTS: The mean number of insects caught by the original trap was 1.25 (standard deviation = 1.28), while the average obtained with the modified trap was 8.88 (standard deviation = 3.44). The medians were statistically different (p = 0.001) according to the Mann-Whitney test. CONCLUSIONS: The modification of Adultrap® increased the average catch of Ae. aegypti by up to seven times.

Distribution and ecotoxicology of bioavailable metals and As in surface sediments of Paraguaçu estuary, Todos os Santos Bay, Brazil.

Surface sediments collected in the intertidal zone of Paraguaçu estuary in July, 2013, were analyzed for organic matter, nitrogen, phosphorus, grain size fractions and partial concentrations of 16 metals. The USEPA 3051A method and ICP-OES and CV-AAS techniques were chosen to metal analysis. Pollution indices (EF, Igeo and PIN) and a comparison with sediment quality guidelines (UET, ERL, ERM, TEL and PEL of NOAA) were conducted in order to evaluate the potential metal impacts over the area. Principal Component Analysis (PCA) and Pearson correlation results showed the importance of organic matter content and the fine-grained fraction of sediments on the control of the bioavailable metals distribution. The Paraguaçu estuary already has anthropogenic enrichment relative to the background level, especially for Mn, whose values exceeded almost 30 times the background at one site (Mn: 1197.30 mg kg(-1)). However, metal levels are still below the reference values with the exception of Hg at one site (Hg: 0.25 mg kg(-1), exceeded TEL and ERL).

Comparison of two coproparasitological techniques for the detection of Platynosomum sp. infection in cats.

Platynosomum sp. is the etiologic agent of platynosomiasis, a hepatic disease that affects domestic cats. The parasite develops in the bile ducts and gallbladder, causing severe hepato-biliary disease. Considering the importance of the disease and the increase in the number of households with cats, the aim of this study was to compare two different techniques for the detection of the parasite's eggs and to assess the frequency of Platynosomum sp. infection in cats. Forty fecal samples from cats of different ages, from an animal shelter in the city of Salvador, Bahia State, Brazil, were subjected to two different techniques: a centrifugal fecal flotation procedure in Sheather's sugar solution and centrifugal sedimentation in formalin-ether solution. Positive results were found for 12.5% of the samples using the centrifugal fecal flotation assay, whereas all samples were negative when employing the centrifugal sedimentation test. The results suggest that this parasite can be found infecting cats in Salvador city and that centrifugal fecal flotation in sugar solution can be a more suitable detection of the parasite's eggs at fecal samples. Therefore, platynosomiasis must be included in the diseases to be studied routinely in domestic felids.

Subtidal benthic macroinfaunal assemblages in tropical estuaries: generality amongst highly variable gradients.

South American estuaries are frequently not included in the search for general ecological models and studies dealing with biological assemblages in estuaries frequently do not sample the entire salinity gradient. We sampled three tropical estuaries, two times each, on ten stations distributed along each system. Six replicates were collected in each station for the benthic macroinfauna and sediment samples for grain size and inorganic contaminant analyses. There were finer sediments at the lower than at the upper estuarine portions. There was a decrease in the diversity, at family level, from marine to freshwater and the differences on the structure of the benthic assemblages were mostly spatial. In spite of the many different characteristics of the three estuaries (e.g. catchment size, pollution levels, proximity with the inner continental shelf) several consistent patterns of benthic macrofauna distribution along these systems were still observed. It suggested a general empirical model regarding the distribution of different benthic invertebrates along tropical salinity gradients which can be tested in different estuaries around the world.