Bioelectrogenesis with microbial fuel cells (MFCs) using the microalga Chlorella vulgaris and bacterial communities

Background: Microbial Fuel Cell (MFC) technology is used in various applications such as wastewater treatment with the production of electrical energy. The objective of this study was to estimate the biodepuration of oils and fats, the elimination of blue dye brl and bioelectro-characterization in MFCs with Chlorella vulgaris and bacterial community. Results: The operation of MFCs at 32 d showed an increase in bioelectrogenic activity (from 23.17 to 327.67 mW/m2 ) and in the potential (from 200 to 954 mV), with biodepuration of fats and oils (95%) in the microalgal cathode, and a removal of the chemical oxygen demand COD (anode, 71%, cathode, 78.6%) and the blue dye brl (73%) at the anode, here biofilms were formed by the bacterial community consisting of Actinobacteria and Deltaproteobacteria. Conclusions: These findings suggest that MFCs with C. vulgaris and bacterial community have a simultaneous efficiency in the production of bioelectricity and bioremediation processes, becoming an important source of bioenergy in the future.

Immobilization of ammonia-oxidizing bacteria by polyvinyl alcohol and sodium alginate

Abstract Ammonia-oxidizing bacteria were immobilized by polyvinyl alcohol (PVA) and sodium alginate. The immobilization conditions and ammonia oxidation ability of the immobilized bacteria were investigated. The following immobilization conditions were observed to be optimal: PVA, 12%; sodium alginate, 1.1%; calcium chloride, 1.0%; inoculum concentration, 1.3 immobilized balls/mL of immobilized medium; pH, 10; and temperature, 30 °C. The immobilized ammonia-oxidizing bacteria exhibited strong ammonia oxidation ability even after being recycled four times. The ammonia nitrogen removal rate of the immobilized ammonia-oxidizing bacteria reached 90.30% under the optimal immobilization conditions. When compared with ammonia-oxidizing bacteria immobilized by sodium alginate alone, the bacteria immobilized by PVA and sodium alginate were superior with respect to pH resistance, the number of reuses, material cost, heat resistance, and ammonia oxidation ability.

Bacterias nosocomiales emergentes: Infección endovascular por Elizabethkingia meningoseptica / Emerging nosocomial bacteria: Endovascular infection by Elizabethkingia meningoseptica

Elizabethkingia meningoseptica es un bacilo gram negativo no fermentador, no móvil, y oxidasa positivo, ampliamente distribuido en la naturaleza pero poco frecuente en humanos, en quienes se considera un patógeno oportunista, actualmente denominado emergente. En el ambiente hospitalario se ha encontrado en superficies húmedas y en equipos médicos, soluciones que habitualmente se utilizan de forma intravenosa, y en medicamentos de reconstitución. Puede causar infección en personas inmunocomprometidas o con enfermedades debilitantes concomitantes. Además, posee enzimas de resistencia frente a los antibióticos prescritos usualmente contra las bacterias gram negativas. Se presenta un caso de bacteriemia por E. meningoseptica en un paciente con antecedente de enfermedad renal crónica, quien recibía tratamiento hemodíalítico 3 veces por semana, desde hace 2 años, al ingreso se documentó infección del sitio de inserción del catéter venoso central, y posteriormente se aisló en los hemocultivos periféricos el crecimiento de la bacteria E. meningoseptica, el paciente cumplió tratamiento con trimetroprim-sulfametoxazol por 14 días con adecuada evolución clínica, sin complicaciones...(AU)

Elizabethkingia meningoseptica is a non fermenter bacilli gram negative, non-mobile, and positive oxidase, widely distributed in nature but rare in humans, in whom it is considered an opportunistic pathogen, now called emerging. In the hospital environment it was found on wet surfaces and medical equipment, solutions usually used intravenously, and drug reconstitution. It can cause infection in immunocompromised or with concomitant debilitating diseases people. It also has resistance to enzymes usually prescribed antibiotics against gram negative bacteria. A case of bacteremia is presented by E. meningoseptica in a patient with a history of chronic kidney disease, who received hemodialysis 3 times a week, for 2 years, entry site infection insertion of central venous catheter was documented and later was isolated from peripheral blood cultures the growth of bacteria E. meningoseptica, the patient completed treatment with trimethoprim-sulfamethoxazole for 14 days with adequate clinical course without complications...(AU)

Assessing the sources of high fecal coliform levels at an urban tropical beach

Recreational water quality is commonly assessed by microbial indicators such as fecal coliforms. Maceió is the capital of Alagoas state, located in tropical northeastern Brazil. Its beaches are considered as the most beautiful urban beaches in the country. Jatiúca Beach in Maceió was found to be unsuitable for bathing continuously during the year of 2011. The same level of contamination was not observed in surrounding beaches. The aim of this study was to initiate the search for the sources of these high coliform levels, so that contamination can be eventually mitigated. We performed a retrospective analysis of historical results of fecal coliform concentrations from 2006 to 2012 at five monitoring stations located in the study region. Results showed that Jatiúca Beach consistently presented the worst quality among the studied beaches. A field survey was conducted to identify existing point and non-point sources of pollution in the area. Monitoring in the vicinity of Jatiúca was spatially intensified. Fecal coliform concentrations were categorized according to tide range and tide stage. A storm drain located in northern Jatiúca was identified as the main point source of the contamination. However, fecal coliform concentrations at Jatiúca were high during high tides and spring tides even when this point source was inactive (no rainfall). We hypothesize that high fecal coliform levels in Jatiúca Beach may also be caused by aquifer contamination or, more likely, from tide washing of contaminated sand. Both of these hypotheses will be further investigated.

Antimicrobial activity of Aspilia latissima (Asteraceae)

Abstract We evaluated the antimicrobial activity of Aspilia latissima - an abundant plant from the Brazilian Pantanal region - against Candida albicans, Candida parapsilosis, Candida krusei, Candida tropicalis, Pseudomonas aeruginosa, Enterococcus faecalis, Escherichia coli and Staphylococcus aureus. The crude extracts and fractions showed activity in all tested microorganisms. The chloroform fraction of the leaves and roots showed the most antimicrobial activity against S. aureus, with an MIC of 500 μg/mL. This fraction was submitted to bioautographic assays to characterize the activity of the compounds. Two bands from the leaves (L-A and L-B) and three bands from the roots (R-C, R-D and R-E) were bioactive. Within the root-derived bands, the terpene derivatives stigmasterol, kaurenoic acid and kaura-9(11), 16-dien-18-oic acid were identified. Antibiotic activity of A. latissima is reported for the first time.

Biocompatibility of the bacterial cellulose hydrogel in subcutaneous tissue of rabbits

PURPOSE: To evaluate the biocompatibility and local sensibility reaction to bacterial cellulose hydrogel (0.8%) implanted in subcutaneous tissue of rabbits. METHODS: Fifteen New Zeland rabbits were randomly allocated into three groups: T1, 7 days, T2, 21 days, and T3, 84 days. The new material was implanted in the subcutaneous tissue of the ear; on the scalp over the periosteum; and on the outer and inner surfaces of the thighs, in the aponeurosis of the muscle. At 7, 21 and 84 postoperative days, the material was collected for histological study. The clinical signs, inflammatory response, angiogenesis and fibrogenesis were variables used for analysis of the biocompatibility and biological reactivity to BCH. Analyses were performed with an AXIO(r) Imager. The statistical tests were performed using the GraphPad Prism 5.0 program(r) RESULTS: The intensity of the inflammatory infiltrate, considering the different cell types (PMN, LMN and GC), was statistically significant, with group T1 different from groups T2 and T3 (p = 0.0124 and p <0.0001, respectively) and T2 different from the T3 group (p = 0.0007). Fibrogenesis grade 1 was the most prevalent in groups T1 (55.4%) and T2 (44.6%). The formation of neovascularization in the group was identified in 84.4% of samples. CONCLUSION: Bacterial cellulose hydrogel (0.8%) is biocompatible, integrating with the subcutaneous tissue of rabbits and inducing tissue remodeling. .

Association between the Brazilian Breastfeeding Network implementation and breastfeeding indicators / Associação entre a implantação da Rede Amamenta Brasil e indicadores de aleitamento materno

OBJECTIVE: To estimate the association between the implementation of the Brazilian Breastfeeding Network and prevalence of breastfeeding in a medium-size city in southern Brazil. METHODS: This was a cross-sectional study involving 405 children under 1 year who participated in the second phase of the multivaccination campaign in 2012. Children's consumption of food on the day before the interview was obtained through interviews with mothers or guardians. The manager and one health professional from every health facility that joined the Network were interviewed in order to investigate the process of implementation of this initiative. The association between prevalence of breastfeeding and exclusive breastfeeding and adherence to the Network implementation process was tested using Poisson regression with robust variance. RESULTS: Multivariate analysis revealed that among the children assisted by health facilities who joined the Network and those attending services that did not adhere to this strategy, the prevalence of breastfeeding (74% and 70.4% among children under 1 year, respectively) and exclusive breastfeeding (43.3% and 38.1% among children under 6 months, respectively) did not differ significantly. Difficulties in implementing the Network, such as high turnover of professionals, not meeting the criteria for accreditation, and insufficient participation of tutors in the process were identified. CONCLUSION: Contrary to the hypothesis of this study, there was no significant association between the implementation of the Brazilian Breastfeeding Network and prevalence of breastfeeding and exclusive breastfeeding in the studied city. It is possible that the difficulties found in implementing the Network in this city have influenced this result. .

OBJETIVO: Estimar a associação entre a implementação da Rede Amamenta Brasil e as prevalências de aleitamento materno (AM) em um município de médio porte do sul do Brasil. MÉTODOS: Estudo transversal que envolveu 405 crianças menores de um ano que participaram da segunda fase da campanha de multivacinação de 2012. O consumo de alimentos pela criança no dia anterior à entrevista foi obtido mediante entrevistas com as mães ou os responsáveis. Para investigar o processo de implementação da rede foram entrevistados o gerente e um profissional de saúde de cada unidade que aderiu a esse processo. A associação entre as prevalências de AM e AM exclusivo e a adesão ao processo de implementação da rede foi testada com a regressão de Poisson com variância robusta. RESULTADOS: A análise multivariada revelou que entre as crianças assistidas por unidades que aderiram ao processo de implementação da rede e as que frequentam serviços que não aderiram a essa estratégia as prevalências de AM (74% e 70,4% em menores de um ano, respectivamente) e AME (43,3% e 38,1% em menores de seis meses, respectivamente) não diferiram significativamente. Foram identificadas dificuldades na implementação da rede, tais como alta rotatividade dos profissionais, não cumprimento dos critérios para certificação e acompanhamento insuficiente das unidades pelos tutores da rede. CONCLUSÃO: Contrariando a nossa hipótese, não houve associação significativa entre a implementação da Rede Amamenta Brasil e as prevalências de AM e AME no município estudado. É possível que as dificuldades encontradas na implementação da rede nesse município tenham influenciado esse resultado. .

Fermenation Products of β-Mannanase Producing Bacteria Inhibit Selected Poultry Borne Pathogens.

Aim: The study evaluated the inhibitory effect of fermentation products of β-mannanaseproducing bacteria on selected poultry borne pathogens. Study Design: The first experiment, bacterial isolates previously confirmed positive for mannanase by plate assay technique were further screened for mannanase production in submerged state fermentation. In the second experiment, inhibitory effect of fermentation products of mannanase-producing bacteria on selected poultry pathogens was evaluated. Place and Duration of Study: Microbiology Research Laboratory, Federal University of Technology, Akure Nigeria between September 2011 and March 2012. Methodology: Bacterial isolates from agricultural wastes previously confirmed positive for mannanase activity by plate assay were further screened for their potential performance under submerged state fermentation and enzyme activity determined by dinitrosalicylic acid method. The inhibitory action of β-mannanase-producing bacteria was determined by supplementation of supernatant and plating method. Results: Isolate 1A showed highest mannanase activity (13.430 U/ml), displayed broad inhibition to selected poultry borne pathogens; Klebsiella oxytoca, Shigella alkalescens, Escherichia coli, Salmonella typhii, Staphylococcus aureus and Streptococcus sp. Apart from isolate 1A, fermentation products of other isolates generated from the mannolytic action of β-mannanase on mannan containing substrate displayed different percentage inhibition on selected poultry borne pathogens. Conclusion: The results suggested that fermentation products from β-mannanaseproducing bacteria might possess antibacterial properties which could be applied in poultry farms.

Investigation of indoor and outdoor air bacterial density in Tehran subway system

The wide use of subway system by citizens underlines the importance of hygienic issues including indoor air pollution in these public places especially in metro stations. The aim of this study was to investigate the bacterial contamination in indoor and outdoor air of two metro stations [Imam Khomeini and Sadeghiyeh stations] in Tehran subway system. In this cross sectional study, three sampling locations were selected in each station. Also, sampling was conducted in indoor air of two types [old and new] of trains. The range of bacterial colony count was 35-1501 CFU/m[3]. Maximum and minimum bacterial contamination levels in Imam Khomeini and Sadeghiyeh platform stations were averagely 1073 CFU/m[3] and 242 CFU/m[3], respectively. 14 bacterial species and genera were isolated; among them the dominant species were Staphylococcus epidermidis, Micrococcus luteus and Bacillus spp. Results showed that bacterial concentrations in indoor air were higher than the outdoor air; also the bacterial counts correlated significantly with number of the passengers [p<0.001] and air temperature [p<0.001]

Anticancer and apoptosis-inducing activities of microbial metabolites

The problems of systemic toxicity and drug resistance in cancer chemotherapy urge the continuing discovery of new anticancer agents. We explored the specific anticancer activity from microbial metabolites to find new lead compound. 394 microbial extracts were evaluated on anti-proliferative activity against 4 cancer cell lines using MTT assay. Of these, 20 samples showed varying degree of cytotoxicity but specifically to the cancer cell lines since the growth of normal cells was not significantly inhibited by 1 mg/ml of each cell extracts. The 4 most potent extracts exhibited strongest growth inhibition to each cancer cell type were selected for further studied. Cell morphological changes such as cell shrinkage, lose of surface contact and blebbing were observed in all treated cancer cells. DNA-binding dye staining demonstrated nuclear condensation and fragmentation. Chromosomal DNA cleavage detected as DNA ladder pattern by gel electrophoresis including activation of cellular caspase-3 activity, a hallmark of apoptosis, were observed in all treated cancer cell lines. These characteristics suggested the mechanism of apoptosis cell death induced by the extracts. No growth inhibition and apoptosis characteristic were detected in normal cells even at high concentration used suggesting the selective cytotoxicity and potential candidates to develop as anticancer agents.

Crystal habits and magnetic microstructures of magnetosomes in coccoid magnetotactic bacteria

Nós relatamos a aplicação de holografia não-axial e microscopia eletrônica de alta resolução para estudar os hábitos cristalinos de magnetossomos e a microestrutura magnética de dois morfotipos de cocos de bactérias magnetotáticas coletadas em uma lagoa salobra em Itaipu, Brasil. Itaipu-1, o organismo cocóide maior, contémduas cadeias separadas de magnetossomos atipicamente grandes; os cristais dos magnetossomos possuem projeções aproximadamente quadradas, comprimentos deaté 250 nm e são ligeiramente alongados na direção [111] (razão largura/comprimento de aproximadamente 0.9).Os cristais dos magnetossomos em Itaipu-3 possuemcomprimentos até 120 nm, maior alongamento na direção [111] (largura/comprimento ~ 0.6), e proeminentes facetas nas extremidades. Os resultados mostram que os hábitos cristalinos dos magnetossomos em Itaipu-1 eItaipu-3 são relacionados, diferindo apenas nos tamanhos relativos das suas faces cristalinas. Em ambos os casos, os cristais são alinhados com seus eixos de alongamento [111] paralelos à direção da cadeia. Em Itaipu-1, mas não em Itaipu-3, o posicionamento cristalográfico, perpendicular à direção [111], de cristais sucessivos na cadeia de magnetossomos parece estar sobre controlebiológico. Enquanto os magnetossomos grandes em Itaipu-1 são monodomínios magnéticos metaestáveis, em Itaipu-3 eles são monodomínios magnéticos permanentes como na maioria das bactérias.

Preferred amino acids and thermostability

Most organisms grow at temperatures from 20 to 50 degrees C, but some prokaryotes, including Archaea and Bacteria, are capable of withstanding higher temperatures, from 60 to >100 degrees C. Their biomolecules, especially proteins, must be sufficiently stable to function under these extreme conditions; however, the basis for thermostability remains elusive. We investigated the preferential usage of certain groupings of amino acids and codons in thermally adapted organisms, by comparative proteome analysis, using 28 complete genomes from 18 mesophiles (M), 4 thermophiles (T), and 6 hyperthermophiles (HT). Whenever the percent of glutamate (E) and lysine (K) increased in the HT proteomes, the percent of glutamine (Q) and histidine (H) decreased, so that the E + K/Q + H ratio was >4.5; it was <2.5 in the M proteomes, and 3.2 to 4.6 in T. The E + K/Q + H ratios for chaperonins, potentially thermostable proteins, were higher than their proteome ratios, whereas for DNA ligases, which are not necessarily thermostable, they followed the proteome ratios. Analysis of codon usage revealed that HT had more AGR codons for Arg than they did CGN codons, which were more common in mesophiles. The E + K/Q + H ratio may provide a useful marker for distinguishing HT, T and M prokaryotes, and the high percentage of the amino acid couple E + K, consistently associated with a low percentage of the pair Q + H, could contribute to protein thermostability. The preponderance of AGR codons for Arg is a signature of all HT so far analyzed. The E + K/Q + H ratio and the codon bias for Arg are apparently not related to phylogeny. HT members of the Bacteria show the same values as the HT members of the Archaea; the values for T organisms are related to their lifestyle (intermediate temperature) and not to their domain (Archaea) and the values for M are similar in Eukarya, Bacteria and Archaea

Bioluminescent bacteria: lux genes as environmental biosensors

Bioluminescent bacteria are widespread in natural environments. Over the years, many researchers have been studying the physiology, biochemistry and genetic control of bacterial bioluminescence. These discoveries have revolutionized the area of Environmental Microbiology through the use of luminescent genes as biosensors for environmental studies. This paper will review the chronology of scientific discoveries on bacterial bioluminescence and the current applications of bioluminescence in environmental studies, with special emphasis on the Microtox toxicity bioassay. Also, the general ecological significance of bioluminescence will be addressed.

Development of a computer software for analysis of SDS-PAGE protein fingerprints of bacterial isolates.

Protein fingerprinting is a widely used technique in epidemiological studies for typing bacterial strains. This study reports the development of a computer based gel analysis system. The system has the capability to analyse SDS-PAGE whole-cell protein profiles using digital image processing techniques. The software incorporates spatial and frequency domain operators for image enhancement, support for geometric correction of images and new algorithms for identification of strain tracks and protein bands. The system also provides facilities for correcting imaging defects for inter-gel comparison, similarity analysis, clustering and pictorial representation of results as a dendrogram. The software is highly interactive, user-friendly and can produce accurate results for differentiation of bacterial strains with minimal overhead of time.

Areas estériles en la industria farmacéutica / Sterile area in the farmaceutical industry

En el presente trabajo se exponen las experiencias en la industria farmacéutica con respecto a las áreas estériles: conceptos, fuentes de contaminación, sistemas fundamentales para la esterilización, flujo laminar, etc., y en general todas las precauciones que se deben tomar en cuenta en tan importante área de la industria farmacéutica

Permanencia de la actividad larvicida de Bacillus sphaericus strains 2362 y 2297 en larvas muestras de CX quinquefasciatus (díptera-culicidae) / Permanence of larvicidad activity of bacillus sphaericus strains 2362 and 2297 in dead (diptera-culicidae)

Mediante bioensayos de laboratorio fue evaluada la persistencia de la toxicidad de Bacillus sphaericus cepas 2362 y 2297 sobre larvas de Culex quinquefasciatus, por eso formulaciones de B.sphaericus 2362 con título de 1,10x10 a la 9 esp/ml y cepa 2297 con título de 1,14x10 a la 9 esp/ml a una concentración de 1.000 ppm. Fueron ensayadas frente a 50 larvas de II Instar de Cx. quinquefasciatus provenientes de insectario. Se hicieron dos series, una en la cual se extraían los cadáveres de larvas a las 72 horas y otra en la cual los cadáveres no se retiraban. Cada semana se colocaban 50 larvas sanas en cada recipiente. La mortalidad fue evaluada a las 72 horas en la primera fase de experimentación y después cada 7 días durante 15 semanas. Desde la 7a. a la 10a. semana existió una disminución estadísticamente significativa en la mortalidad alcanzada en los bioensayos donde se retiraban los cadáveres, la cual fue recuperada a la 11a. semana alcanzando una mortalidad de 98 por ciento al 100 por ciento debido a que al momento de extraen los cadáveres éstos estaban casi desintegrados por la acción de la toxina y era difícil extraerlos completos, permaneciendo en esos restos esporas viables tóxicas para larvas sanas. En la serie donde los cadáveres no se retiraban, la mortalidad observada fue del 99 por ciento al 100 por ciento durante las 15 semanas