Enhanced low-cost lipopeptide biosurfactant production by Bacillus velezensis from residual glycerin.

Biosurfactants (BSFs) are molecules produced by microorganisms from various carbon sources, with applications in bioremediation and petroleum recovery. However, the production cost limits large-scale applications. This study optimized BSFs production by Bacillus velezensis (strain MO13) using residual glycerin as a substrate. The spherical quadratic central composite design (CCD) model was used to standardize carbon source concentration (30 g/L), temperature (34 °C), pH (7.2), stirring (239 rpm), and aeration (0.775 vvm) in a 5-L bioreactor. Maximum BSFs production reached 1527.6 mg/L of surfactins and 176.88 mg/L of iturins, a threefold increase through optimization. Microbial development, substrate consumption, concentration of BSFs, and surface tension were also evaluated on the bioprocess dynamics. Mass spectrometry Q-TOF-MS identified five surfactin and two iturin isoforms produced by B. velezensis MO13. This study demonstrates significant progress on BSF production using industrial waste as a microbial substrate, surpassing reported concentrations in the literature.

Distribution of genetically characterized yeasts and its antifungals susceptibility in the hospital environment.

Candida spp. is one of the main pathogens associated with nosocomial infection in Brazil and worldwide. The aim of this study was to evaluate the distribution of Candida yeasts in the ICU and their susceptibility to the antifungal agents terbinafine and fluconazole. The samples were collected by swabbing nine surfaces in the ICU of a hospital located in Pelotas, RS. These isolates were genetically characterized by sequencing the internal transcript spacer (ITS) using the primers ITS1 and ITS4. The test against antifungals was performed by Microdilution in Broth (CLSI-M27-A4). 64 yeasts identified as Candida parapsilosis (45.31%; n = 29), Meyerozyma (Pichia) guilliermondii (28.12%; n = 18), Claviceps lusitaneae (25%; n = 16) and Candida tropicalis (1, 56%; n = 1) mostly at the counter used for handling medicines and food distribution (68.75%; n = 44). Susceptibility to antifungals varied between species. These results describe potentially pathogenic Candida species as contaminants in the ICU environment. The study environment is a potential source of exogenous infection for hospitalized patients.

Data from the numerical analysis of radial and tangential leakage of gas in scroll compressors.

The data presented herein are related to the simulations and correlations reported in the article entitled "Numerical analysis and correlations for radial and tangential leakage of gas in scroll compressors" [1]. The numerical simulations were carried out using the ANSYS FLUENT 12.1.4 CFD code, which is based on the finite volume method. Details of the numerical modeling setup and data collection are provided to allow reproducibility. The datasets include predicted values of radial and tangential leakage carried out using ANSYS FLUENT 12.1.4 CFD code for different gases, operating conditions and geometries expressed as dimensionless parameters. The scripts in C++ for the correlations of radial and tangential leakages developed based on the numerical predictions are also provided together with experimental and numerical data used to validate the correlations.

MBSP1: a biosurfactant protein derived from a metagenomic library with activity in oil degradation.

Microorganisms represent the most abundant biomass on the planet; however, because of several cultivation technique limitations, most of this genetic patrimony has been inaccessible. Due to the advent of metagenomic methodologies, such limitations have been overcome. Prevailing over these limitations enabled the genetic pool of non-cultivable microorganisms to be exploited for improvements in the development of biotechnological products. By utilising a metagenomic approach, we identified a new gene related to biosurfactant production and hydrocarbon degradation. Environmental DNA was extracted from soil samples collected on the banks of the Jundiaí River (Natal, Brazil), and a metagenomic library was constructed. Functional screening identified the clone 3C6, which was positive for the biosurfactant protein and revealed an open reading frame (ORF) with high similarity to sequences encoding a hypothetical protein from species of the family Halobacteriaceae. This protein was purified and exhibited biosurfactant activity. Due to these properties, this protein was named metagenomic biosurfactant protein 1 (MBSP1). In addition, E. coli RosettaTM (DE3) strain cells transformed with the MBSP1 clone showed an increase in aliphatic hydrocarbon degradation. In this study, we described a single gene encoding a protein with marked tensoactive properties that can be produced in a host cell, such as Escherichia coli, without substrate dependence. Furthermore, MBSP1 has been demonstrated as the first protein with these characteristics described in the Archaea or Bacteria domains.

Avaliação antifúngica de uma solução à base de glucoprotamina e do óleo essencial de Cymbopogon citratusem leveduras de ambiente hospitalar / Antifungal action of a solution based on the glucoprotamine and the essential oil from Cymbopogon citratus on the yeasts from the hospital environment

O objetivo deste estudo foi de avaliar a atividade antifúngica de uma solução à base de glucoprotamina (GLU) e de óleo essencial (OE) de Cymbopogon citratus. Candida tropicalis, Claviceps lusitaniae, Meyerozyma (Pichia) guilliermondii e Candida parapsilosis foram isoladas das superfícies de um hospital público de Pelotas, RS. A atividade antifúngica da GLU foi analisada nas concentrações de 0,25% a 0,0005%, e para o OE, obtido por Clevenger, foi utilizado nas concentrações de 17.500 µg/mL a 0,034 µg/mL. A análise cromatográfica foi efetuada por meio de CG/MS. A atividade anti-Candidafoi analisada pela técnica de Microdiluição em Caldo para determinar a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM). A inibição pela GLU ocorreu em todas as concentrações testadas, enquanto o OE apresentou resultado de CIM que oscilou de 2846 a 5450 µg/mL, e CFM de 2853 a 5330 µg/mL. Alfa­citral (37,10%), beta­citral (32,77% e beta-mirceno (18,75%) foram considerados como os compostos majoritários do OE. Os dados obtidos neste trabalho destacam a atividade antifúngica da solução à base de GLU e do OE de C. citratus na eliminação dos isolados de Candida spp ambientais. (AU)

This study aimed at evaluating the antifungal activity of glucoprotamine solution (GLU) and the essential oil from Cymbopogon citratus (EO). Candida tropicalis, Claviceps lusitaniae, Meyerozyma(Pichia) guilliermondii and Candida parapsilosis were isolated from the samples, which were collected from the surfaces of a public hospital located in Pelotas, RS. The antifungal activity of GLU was detected at the concentrations from 0.25% to 0.0005%, while the EO, by Clevenger, was used at concentrations from 17.500 µg mL to 0.034 µg/mL. Chemical analysis was determined by GC/MS. The anti-Candida activity was performed by using Broth Microdilution technique to determine the Minimal Fungicidal Concentration (MFC) and the Minimal Inhibitory Concentration (MIC). The inhibition by GLU occurred at all of the tested concentrations, whereas the EO showed MIC ranging from 2.846 to 5.450 µ/mL and the CFM from 2.853 to 5.330 µg/mL. Alfa­citral (37.10%), beta­citral (32.77%) and beta-mirceno (18.75%) were the majority compounds in the EO. The data obtained in the present study highlight the effectiveness of the solution based on GLU and EO for eliminating the environmental isolates of Candida spp. (AU)

Avaliação antifúngica de uma solução à base de glucoprotamina e do óleo essencial de Cymbopogon citratus em leveduras de ambiente hospitalar / Antifungal action of a solution based on the glucoprotamine and the essential oil from Cymbopogon citratus on the yeasts from the hospital environment

O objetivo deste estudo foi de avaliar a atividade antifúngica de uma solução à base de glucoprotamina (GLU) e de óleo essencial (OE) de Cymbopogon citratus. Candida tropicalis, Claviceps lusitaniae, Meyerozyma (Pichia) guilliermondii e Candida parapsilosis foram isoladas das superfícies de um hospital público de Pelotas, RS. A atividade antifúngica da GLU foi analisada nas concentrações de 0,25% a 0,0005%, e para o OE, obtido por Clevenger, foi utilizado nas concentrações de 17.500 μg/mL a 0,034 μg/mL. A análise cromatográfica foi efetuada por meio de CG/MS. A atividade anti-Candida foi analisada pela técnica de Microdiluição em Caldo para determinar a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM). A inibição pela GLU ocorreu em todas as concentrações testadas, enquanto o OE apresentou resultado de CIM que oscilou de 2846 a 5450 μg/mL, e CFM de 2853 a 5330 μg/mL. Alfa–citral (37,10%), beta–citral (32,77% e beta-mirceno (18,75%) foram considerados como os compostos majoritários do OE. Os dados obtidos neste trabalho destacam a atividade antifúngica da solução à base de GLU e do OE de C. citratus na eliminação dos isolados de Candida spp ambientais.

This study aimed at evaluating the antifungal activity of glucoprotamine solution (GLU) and the essential oil from Cymbopogon citratus (EO). Candida tropicalis, Claviceps lusitaniae, Meyerozyma (Pichia) guilliermondii and Candida parapsilosis were isolated from the samples, which were collected from the surfaces of a public hospital located in Pelotas, RS. The antifungal activity of GLU was detected at the concentrations from 0.25% to 0.0005%, while the EO, by Clevenger, was used at concentrations from 17.500 μg mL to 0.034 μg/mL. Chemical analysis was determined by GC/MS. The anti-Candida activity was performed by using Broth Microdilution technique to determine the Minimal Fungicidal Concentration (MFC) and the Minimal Inhibitory Concentration (MIC). The inhibition by GLU occurred at all of the tested concentrations, whereas the EO showed MIC ranging from 2.846 to 5.450 μ/mL and the CFM from 2.853 to 5.330 μg/mL. Alfa–citral (37.10%), beta–citral (32.77%) and beta-mirceno (18.75%) were the majority compounds in the EO. The data obtained in the present study highlight the effectiveness of the solution based on GLU and EO for eliminating the environmental isolates of Candida spp.

Blood lactate increases with the progression of mitral valve disease in dogs / Aumento de lactato sanguíneo com progressão de valvopatia mitral em cães

In dogs with congestive heart failure, the upregulated sympathetic tone causes vasoconstriction that impairs peripheral blood supply, therefore causing the accumulation of lactate. In this prospective cross-sectional study with a longitudinal component, blood lactate was quantified in 10 healthy and 34 myxomatous mitral valve disease (MMVD) dogs to investigate its potential use as a diagnostic and prognostic biomarker. While there were no differences in lactate concentration between control animals and stages B1 (3.31±0.62mmol/L) and B2 (3.32±0.46mmol/L) dogs, significant differences were found between healthy (2.50±0.69mmol/L) and both C (3.99±0.47mmol/L) and D (6.97±1.23mmol/L) animals. When a cut-off of 3.35mmol/L was used, lactate was able to distinguish dogs with normal and remodeled hearts with a sensitivity of 78.2% and specificity of 63.6%. Also, significant correlations existed between lactate and indicators of cardiac remodeling. Finally, animals with blood lactate <3.5mmol/L carried a better prognosis when compared with dogs in which lactate was >5.0mmol/L. Our results suggest that the progression of MMVD results in accumulation of lactate within the bloodstream, which is likely attributable to the impaired peripheral tissue perfusion. In MMVD dogs, blood lactate may be used as a surrogate for cardiac remodeling, and an increased concentration is associated with a worse prognosis regarding the time to evolve into congestive heart failure.(AU)

Em cães com insuficiência cardíaca congestiva, o tônus simpático hiperregulado causa vasoconstrição e interfere com o suprimento sanguíneo periférico, resultando no acúmulo de lactato. Neste estudo prospectivo transversal com um componente longitudinal, o lactato sanguíneo foi quantificado em 10 cães saudáveis e 34 cães com doença mixomatosa da valva mitral (DMVM) para investigar seu potencial como biomarcador diagnóstico e prognóstico. Embora não tenham sido identificadas diferenças na concentração de lactato entre animais controle e cães com DMVM nos estágios B1 (3,31±0,62mmol/L) e B2 (3,32±0,46mmol/L), diferenças significativas foram constatadas entre os cães saudáveis (2,50±0,69mmol/L) e cães com DMVM estágio C (3,99±0,47mmol/L) ou D (6,97±1,23mmol/L). Quando utilizado o valor de corte de 3,35mmol/L, o lactato foi capaz de diferenciar cães com corações normais daqueles com corações remodelados com sensibilidade de 78,2% e especificidade de 63,6%. Além disso, correlações significativas foram encontradas entre o lactato e os indicadores de remodelamento cardíaco. Por fim, os animais com lactato sanguíneo <3,5mmol/L tiveram prognóstico melhor comparativamente aos cães com concentrações >5,0mmol/L. Nossos resultados sugerem que a progressão da DMVM resulta no acúmulo de lactato na corrente sanguínea, fato que é provavelmente atribuído à perfusão periférica prejudicada. Em cães com DMVM, o lactato sanguíneo pode ser utilizado como indicador de remodelamento cardíaco, cuja concentração elevada está associada com pior prognóstico relativo ao tempo para evoluir para insuficiência cardíaca congestiva.(AU)

Development and validation of analytical methodology by GC-FID using hexadecyl propanoate as an internal standard to determine the bovine tallow methyl esters content.

EN 14103:2003 and EN 14103:2011 were developed in order to determine fatty acid methyl ester (FAME) content of biodiesel. The internal standards (IS) of biodiesel include methyl heptadecanoate (MHD) and methyl nonadecanoate (MND), respectively. However, since these ISs are also present in bovine tallow methyl esters (BTME) or overlapping peaks, they have not been efficient. This work proposes an improved BTME determination method by using hexadecyl propanoate (HDP) as an IS. For this purpose, an analytical methodology by Gas Chromatography-Flame Ionization Detector (GC-FID) was developed and validated, where HDP demonstrated selectivity in retention time between peaks C16:1 and C18:0 for coconut and soybeans methyl esters and BTME, as well as resolution >1.5 for the BTME in split mode 30:1. Trueness in the determination of BTME content using the HDP as an IS was statistically equivalent to confidence interval of 95% for the null hypothesis statistic test, even when only 20% of the HDP was utilized in comparison with the IS concentrations defined by EN 14103:2003 and EN 14103:2011. This allowed the biodiesel analysis to be performed five times more with 1 g of HDP. Furthermore, the method developed enabled us to reduce the analysis time by 21.6%, without prejudice to the integration of peaks (C6:0 to C24:1). Regarding the repeatability and intermediate precision tests, results of RSD (%) ≤ 2% were reached. Additionally, the method developed has proved to be robust. HDP is a long-chain fatty alcohol ester absent from feedstocks used in biodiesel synthesis. It presents all of the characteristics for a good IS, ideal for application via internal standardization method, as recommended by EN 14103.

High-resolution electrocardiography in the diagnosis of arrhythmogenic right ventricular cardiomyopathy in Boxer dogs / Eletrocardiografia de alta resolução no diagnóstico da cardiomiopatia arritmogênica do ventrículo direito em cães da raça Boxer

To evaluate the reliability of high-resolution electrocardiography in the diagnosis of arrhythmogenic right ventricular cardiomyopathy in Boxers, 20 dogs with no structural cardiac alterations at echocardiographic examination were grouped on the basis of frequency of ventricular arrhythmias, evaluated by 24-hour ambulatory ECG, and undergoing a high-resolution electrocardiography. High frequency QRS duration, duration of terminal QRS complex less than 40µV (LAS40) and root mean square voltage of the terminal 40 milliseconds of the QRS complex (RMS40) were measured. Differences in high-resolution ECG variables were not observed between groups. Therefore, the results of this investigation suggest that high-resolution electrocardiography is not a useful method for the diagnosis of arrhythmogenic right ventricular cardiomyopathy in Boxers without detectable myocardial alterations or systolic dysfunction.

Com o objetivo de avaliar a importância da eletrocardiografia de alta resolução no diagnóstico da cardiomiopatia arritmogênica do ventrículo direito do Boxer, 20 cães sem evidências de doença cardíaca estrutural à avaliação ecodopplercardiográfica foram agrupados de acordo com a frequência de arritmias ventriculares, avaliadas pela eletrocardiografia ambulatorial de 24 horas, e submetidos ao exame eletrocardiográfico de alta resolução. Duração do complexo QRS filtrado, duração dos sinais de baixa amplitude (menor que 40µV) dos últimos 40 milissegundos do complexo QRS e raiz quadrada média da voltagem ao quadrado dos últimos 40 milissegundos do complexo QRS (RMS40) foram as variáveis avaliadas. Não foram observadas diferenças significativas entre os grupos em relação às variáveis estudadas. Sendo assim, os resultados do presente estudo sugerem que a eletrocardiografia de alta resolução não é uma ferramenta útil no auxílio diagnóstico da cardiomiopatia arritmogênica do ventrículo direito dos cães da raça Boxer que não apresentam alterações miocárdicas evidentes ou disfunção sistólica.

Obstrução intestinal congênita em cão por aderência de alça em osso púbico / Canine congenital intestinal obstruction due to a band of small bowel in the pubic bone

Atendeu-se uma cadela, sem raça definida, com aproximadamente cinco meses de idade, apresentando anamnese com queixa de apatia e hiporexia associadas a vômitos e emagrecimento progressivo com início incerto. Ao exame físico era evidente distensão abdominal com dilatação intestinal e aumento de peristaltismo. O animal apresentava-se emaciado e subdesenvolvido, com acentuado grau de desidratação, pulso filiforme e nível de consciência reduzido. Minutos após o início do atendimento a cadela foi a óbito. À necropsia, pôde-se observar um segmento do intestino delgado atravessando o púbis e com lúmen reduzido. Tal apresentação se faz relevante por se tratar de um caso nunca antes descrito na literatura veterinária.

A five-month-old mongrel bitch was presented with history of apathy and hyporexia in addition to vomit and progressive weight loss of uncertain beginning. At the physical examination, abdominal distention with intestinal dilatation and increased peristaltic movements was evident. The animal also was emaciated, highly dehydrated, with filiform pulse and reduced conscience level. It died a few minutes after the physical exam. At the necropsy, a small bowel segment could be observed crossing the pubic bone causing obstruction due to a reduction in the lumen at the point of adhesion. This presentation has an important relevance because such case has never been reported before in the veterinary medical practice.

Efficient hydrogen production from ethanol and glycerol by vapour-phase reforming processes with new cobalt-based catalysts.

The aim of this study was to investigate biohydrogen production from biofuel-reforming processes using new multi-component bulk-type cobalt-based catalysts. The addition of different components to improve the catalytic performance was studied. Monometallic cobalt catalyst and catalysts containing Ru (ca. 1%) and/or Na (ca. 0.5%) were characterized and tested in the 623-673 K temperature range in ethanol steam reforming (ESR) with a steam/carbon ratio (S/C) of 3. The catalysts showed a high performance for hydrogen production and, except for H(2) and CO(2), only small amounts of by-products were obtained, depending on the temperature and the catalyst used. The catalyst containing both Ru and Na (Co-Ru(Na)) showed the best catalytic behavior in ESR. It operated stably for at least 12 days under cycles of oxidative steam reforming of glycerol/ethanol mixtures (S/C=2) and activation under O(2).