Wort disinfection treatment with electron beam for bioethanol production

Microbial contamination of the wort during the fermentation process causes significant losses in ethanol production worldwide and creates a dependence of the industry on chemicals and antibiotics to control contamination. Therefore, this study used electron beam (e-beam) to disinfect wort from sugarcane (Saccharum officinarum L.) molasses and investigate the bioethanol fermentation. Four treatments (T0 - T3) were carried out using ionizing doses of radiation through the electron accelerator: 0 (control), 10, 20, and 40 kGy. Total mesophiles, total bacteria, sucrose, glucose, fructose, phenolics, flavonoids, hydroxymethylfurfural (5-HMF), and Furfural were measured. An alcoholic fermentation assay was performed after the irradiation process. The irradiated treatments showed no inversion of sugars and formation of the inhibitory by-products flavonoids, furfural and 5-HMF, except for the phenolic compounds. The lower dose tested (10 kGy) reduced more than 99.9 % of the total mesophiles and more than 99.99 % of the total bacteria in the substrate. In the fermentation, the irradiated worts presented similar (p > 0.05) yields (92, 93, and 94 %) and ethanol productivity levels (0.89, 0.88, and 0.87 g L-1 h-1, for T1, T2, and T3 respectively). However, all treatments presented higher yields and productivity (p < 0.05) when compared to the control (88 % and 0.85 g L-1 h-1), highlighting the possible use of e-beam in wort fermentation at a lower dose (10 kGy). This allows reduction in losses caused by microbial contamination, besides increasing fermentation yield and productivity with lower energy consumption.(AU)

New insights into the structural characteristics of irradiated crotamine

Background:Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC).Methods:A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica.Results:Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates.Conclusions:Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in myotoxic activity.(AU)

New insights into the structural characteristics of irradiated crotamine

Background: Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Methods: A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica. Results: Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates. Conclusions: Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in myotoxic activity.(AU)

New insights into the structural characteristics of irradiated crotamine

Background: Since ionizing radiation has the potential to alter the molecular structure and affect the biologica properties of biomolecules, it has been successfully employed to attenuate animal toxins. The present study aimed to characterize the structural modifications on irradiated crotamine, a toxin from Crotalus durissus terrificus venom, using circular dichroism (CD), fluorescence, Fourier transformed infrared spectroscopy (FTIR), atomic force microscopy (AFM) and differential scanning calorimetry (DSC). Methods: A combination of size exclusion and ion-exchange chromatography was used to purify the peptide using crude venom. The pure toxin was then submitted to 2 kGy gamma irradiation doses from a cobalt-60 source. Native and irradiated crotamine were analyzed using a fluorescence spectrophotometer. Wavelength was fixed at 295 nm and fluorescence emission scans were collected from 300 to 400 nm. CD and FTIR techniques were used to identify the secondary structure of both samples. DSC analyses were performed at a starting temperature of 20 °C up to a final temperature of 90 °C. AFM provided a 3D profile of the surfaces of both crotamine forms adsorbed on mica. Results: Fluorescence spectroscopy showed that the quantum yield of the irradiated form decreased. CD spectra of native and irradiated crotamine solutions showed differences between the samples in wavelength, indicating that irradiation induced a transition of a small portion of the random coil regions towards an a-helical conformation. FTIR and CD showed that the native and irradiated crotamine spectra were different with regard to secondary structure. The thermodynamic analysis showed that irradiation caused changes in the calorimetric profile and CD showed that temperature-induced changes also occur in the secondary structure. Finally, AFM showed the possible formation of insoluble aggregates. Conclusions: Our results indicate that irradiation leads to progressive changes in the structure of the toxin, which could explain a decrease in myotoxic activity.

Avaliação ultrassonográfica e radiográfica dos campos pulmonares em cães sadios e com edema pulmonar cardiogênico

O exame ultrassonográfico sempre ocupou papel secundário na avaliação dos campos pulmonares, devido à barreira representada por este tecido aerado à propagação dos feixes ultrassônicos. No final da década de 90, houve um impulso da sua aplicabilidade nesta região, devido ao reconhecimento de diferentes artefatos de reverberação gerados a partir de um pulmão normalmente aerado e quando este se apresenta com o interstício e/ou alvéolos infiltrados. Por ser um exame de baixo custo, livre de radiação ionizante, poder ser realizado em posição ortopneica e poder ser realizado a beira do leito, a avaliação ultrassonográfica do tórax ganhou notoriedade na área do intensivismo. Objetivou-se neste estudo avaliar a aplicabilidade e os aspectos do exame ultrassonográfico na avaliação de campos pulmonares de cães sadios e com edema pulmonar cardiogênico agudo. Foram avaliados 20 cães sadios e 10 cães com insuficiência valvar mitral em edema pulmonar agudo, de raças e idades variadas, machos e fêmeas. Todos os cães foram submetidos a exames físicos, radiográficos, ultrassonográficos e ecocardiográficos. Os animais doentes foram avaliados em três momentos: T0 (na admissão), T1 (4 horas após o início do tratamento) e T2 (24 horas depois). A ausculta, a avaliação radiográfica e o exame ultrassonográfico do tórax foram realizados de forma setorizada, baseados no protocolo de avaliação ultrassonográfico dos campos pulmonares denominado de Veterinary Bedside Lung Ultrasound Exam (VetBLUE): entre o 2° e 3°, 4° e 5°, 6° e 7°, 8° e 9° espaços intercostais, nos hemitórax esquerdo e direito. Para cada região associou-se um escore de acordo com a alteração observada e um escore final para cada modalidade de avaliação. Nos vinte cães avaliados do grupo controle, em todos os espaços intercostais foi de fácil reconhecimento a presença do deslizamento pleural e do artefato de reverberação causado pela superfície pleura-pulmão (linhas A), exceto no 2º-3º espaço, onde essas características foram observadas, porém com maior dificuldade. Sete cães (35%) apresentaram linhas B durante a avalição, porém geralmente o artefato foi observado em apenas um espaço intercostal e no máximo duas linhas por campo. Esse artefato foi mais observado no hemitórax direito e a região mais acometida foi entre o 8º e 9º espaço intercostal, porém sem diferença estatística significativa. No grupo doente, na primeira avaliação do exame ultrassonográfico todos os pacientes apresentaram linhas B em grande quantidade. As avaliações aos exames físico, radiográfico e ultrassonográfico apresentaram um comportamento semelhante ao longo do tempo, demonstrando um escore menor naqueles animais responsivos ao tratamento. A concordância interobservador para o exame ultrassonográfico foi elevada, o que demonstra uma boa repetibilidade do método. Por meio de uma avaliação segmentada de algumas janelas acústicas pode-se obter uma avaliação do tórax do paciente em um tempo curto, melhorandose a tomada de decisões no atendimento emergencial. Contudo, esta técnica não exclui a avaliação por outras modalidades de imagem (exame radiográfico e tomografia computadorizada), e deve representar uma triagem para aqueles pacientes com síndromes respiratórias agudas.

Ultrasound examination has always played a secondary role in pulmonary assessment, as the gas content of the lungs does not favor the propagation of ultrasound beams. However, the recognition of different reverberating artifacts arising from the normal aerated lungs (A lines) or generated in the presence of interstitial and/or alveolar infiltrates (B lines), in the late 1990s, led to wider application of the technique. Ultrasonography is a low cost, ionizing radiation-free bedside imaging modality which can be performed in the orthopneic position with minimal patient restraint, and therefore has gained wide popularity in intensive care. The objective of this study was to evaluate the applicability and aspects of ultrasound examination in the evaluation of pulmonary fields of healthy dogs and dogs with acute cardiogenic pulmonary edema. Twenty healthy dogs and ten dogs with valvar disease presenting acute pulmonary edema were evaluated. All dogs were submitted to physical, radiographic, ultrasonographic and echocardiographic examinations. The animals with edema were evaluated at three times: T0 (admission), T1 (4 hours after initiation of the treatment) and T2 (24 hours later). Auscultation, radiographic and ultrasound examinations were performed using a regionally scan at the 2nd-3rd, 4-5th, 6-7th and 8- 9th intercostal spaces, based on the VetBLUE (Veterinary Bedside Lung Ultrasound Exam) protocol in the right and left hemithoraces. For each region, a score was assigned according to the observed change and a final score for each evaluation modality was given summing the scores of all regions. Pleural sliding and A lines (hyperechoic, parallel equidistant lines arising from the visceral pleura-lung interface) could be easily seen at all intercostal spaces in all dogs in this sample, with more difficult visualization at the 2nd-3rdintercostal space. B lines were observed in seven out of 20 dogs (35%). However, this artifact was limited to one IS and a maximum of two lines were detected per field. B line artifacts were more commonly seen in the right hemithorax and at the level of the 8-9th intercostal space (non-significant differences). In the group with pulmonary edema, in the first evaluation of the ultrasonographic examination all the patients presented B lines in great quantity. Physical, radiographic and ultrasonographic examinations showed a similar behavior over time, showing a lower score in those animals responsive to the treatment. The interobserver agreement for the ultrasonographic examination was high, which demonstrates a good repeatability of the method. Using a segmented evaluation of some acoustic windows it is possible to obtain an evaluation of the patient's chest in a short time, improving the decision-making in the emergency service. However, ultrasonography does not eliminate the need for other imaging modalities such as radiography and computed tomography and should be seen as a screening tool for patients presenting with acute respiratory syndromes.

Aplicação de baixas doses de radiação ionizante no fruto brasileiro tucumã (Astrocarium vulgare Mart) / Application of low doses of ionizing radiation in the Brazilian fruit tucumã (Astrocarium vulgare Mart)

O tucumã (Astrocaryum vulgare Mart.) é um fruto nativo da Amazônia, de ocorrência principal no estado do Pará, mas também encontrado nos estados do nordeste e do centro-oeste brasileiro. O tucumã é considerado como uma excelente fonte de carotenóides com maior concentração em ß-caroteno, precursor da vitamina A, e além dos carotenóides, também é importante fonte de vitamina B2 (riboflavina). Por este motivo, o presente trabalho objetivou analisar os efeitos da irradiação gama sobre o valor nutricional do tucumã. Os frutos de tucumã foram irradiados com as doses de 0,5, 1,0 e 2,0 kGy num irradiador com fonte de césio 137. Foram determinados os teores de carotenóides totais por espectrofotometria. As análises de α e ß-caroteno, tiamina, riboflavina foram realizadas por cromatografia líquida de alta eficiência (CLAE). Foi detectado que o ß-caroteno representa 80% dos carotenóides totais e que com uma dose de 2 kGy ocorreram as maiores reduções de ß-caroteno, cerca de 7,5% em relação ao controle. Os frutos também apresentaram altos teores de riboflavina de 0,183 a 0,222 µg 100 g-1 e mantiveram a estabilidade após o processo de radiação gama, no entanto, os teores de tiamina foram baixos de 0,050 a 0,033 µg 100 g-1, e os frutos irradiados na dose de 2 kGy apresentaram reduções significativas de tiamina, cerca de 34% em relação ao controle.

The tucumã (Astrocaryum vulgare Mart.) is a native fruit of Amazônia, occurring mainly in the state of Pará, but also found in the Brazilian northeast states and in the Brazilian central-western states. The tucumã is considerated an excellent source of carotenoids with a very high concentration of ß-carotene, which is a precursor of vitamin A. In addition to carotenoids it is an important source of vitamin B2 (riboflavin) in fruits. This study aimed to analyze the effects of gamma radiation on the nutritional value of tucumã. The fruits were irradiated at doses of 0.5, 1.0 and 2.0 kGy irradiator with a source of cesium 137. The carotenoids were determined by spectrophotometry. The analysis of α and ß-carotene, thiamin, riboflavin were carried out by high performance liquid chromatography (HPLC). The ß-carotene accounts for 80% of total carotenoids in tucumã, and with a dose of 2 kGy, it showed the highest reduction of ß-carotene, about 7.5% in relation to the control. The tucumã fruit showed high levels of riboflavin from 0.183 to 0.222 µg 100 g-1, and maintained stability after the gamma radiation process. However, it had low levels of thiamine from 0.050 to 0.033 µg 100 g-1, and irradiated at a dose of 2 kGy showed significant reductions of thiamine, about 34% in relation to the control .

TBAR values assessment in irradiated chicken legs / Avaliação do valor de TBARS em coxas de frangos irradiadas

The effect of ionizing radiation in raw, vacuum and modified atmosphere packed chicken legs and storage at 4±1oC was evaluated on the basis of thiobarbituric acid reactive substances (TBARS) The vacuum-packed samples exhibited a gradual increase in TBARS values proportional to the radiation dose in the course of the storage period, but the differences were not statistically significant (p>0.05) up to the fourteenth day when the samples exposed to the different radiation doses applied were compared. Samples irradiated with 1.5 kGy and 3.0 kGy and packaged under modified atmosphere showed significantly lower TBARS values as compared to the vacuum-packaged samples, except after 20 and 26 days storage. The maximum TBARS values were obtained from samples irradiated with 7.0 kGy, with mean values of 2.13 and 1.52 mg.kg-1 of malonaldehyde, for the vacuum and modified atmosphere packages respectively.

O efeito da radiação ionizante em coxas de frango cruas embaladas a vácuo e sob atmosfera modificada e armazenadas a 4±1 ºC foi avaliado a partir da análise de substâncias reativas ao ácido tiobarbitúrico (TBARS). Para amostras embaladas a vácuo foram observados aumentos gradativos nos valores de TBARS conforme o aumento da dose de radiação ionizante para os diferentes dias de armazenamento, porém as diferenças não foram significativas (p>0,05) até o 14º dia quando os respectivos períodos foram comparados. Amostras irradiadas com 1,5 kGy e 3,0 kGy e embaladas sob atmosfera modificada apresentaram valores de TBARS significativamente (p 0,05) menores em relação às respectivas amostras embaladas a vácuo, exceto no 20º e 26º dia de armazenamento. Os maiores valores de TBARS foram obtidos para as amostras irradiadas com 7,0 kGy com médias de 2,13 e 1,52 mg.kg-1 de malonaldeído em embalagem a vácuo e sob atmosfera modificada respectivamente.

Fermentation of irradiated sugarcane must

Bacillus and Lactobacillus are bacteria that usually contaminate the ethanolic fermentation by yeasts and may influence yeast viability. As microorganisms can be killed by ionizing radiation, the efficacy of gamma radiation in reducing the population of certain contaminating bacteria from sugarcane must was examined and, as a consequence, the beneficial effect of lethal doses of radiation on some parameters of yeast-based ethanolic fermentation was verified. Must from sugarcane juice was inoculated with bacteria of the genera Bacillus and Lactobacillus. The contaminated must was irradiated with 2.0, 4.0, 6.0, 8.0 and 10.0 kGy of gamma radiation. After ethanolic fermentation by the yeast (Saccharomyces cerevisiae) the total and volatile acidity produced during the process were evaluated; yeast viability and ethanol yield were also recorded. Treatments of gamma radiation reduced the population of the contaminating bacteria in the sugarcane must. The acidity produced during the fermentation decreased as the dose rate of radiation increased. Conversely, the yeast viability increased as the dose rate of radiation increased. Gamma irradiation was an efficient treatment to decontaminate the must and improved its parameters related to ethanolic fermentation, including ethanol yield, which increased 1.9%.

Bactérias dos gêneros Bacillus e Lactobacillus são microrganismos que normalmente contaminam a fermentação alcoólica realizada por leveduras. Estas bactérias podem causar queda da viabilidade das leveduras. Como a radiação ionizante pode eliminar microrganismos, estudou-se o efeito da radiação gama na redução da população de bactérias contaminantes do mosto de caldo de cana-de-açúcar e verificaram-se seus efeitos sobre alguns parâmetros da fermentação alcoólica. O mosto de caldo de cana-de-açúcar foi inoculado contaminado com bactérias dos gêneros Bacillus e Lactobacillus, e após irradiação com doses de 2,0; 4,0; 6,0; 8,0 e 10,0 kGy de radiação gama, foi efetuado a contagem da população das bactérias. Leveduras Saccharomyces cerevisiae foram inoculadas no mosto irradiado para realizarem a fermentação alcoólica. Após a fermentação, foram determinados a acidez total e a acidez volátil do vinho, a viabilidade das células de levedura e o rendimento da fermentação. O tratamento com radiação gama reduziu a população das bactérias contaminantes do mosto. A acidez produzida durante a fermentação diminuiu com o aumento das doses de radiação aplicadas ao mosto, e viabilidade das leveduras aumentou com o aumento das doses de radiação. A irradiação gama foi um eficiente tratamento para descontaminar o mosto de caldo de cana-de-açúcar e melhorar os parâmetros da fermentação alcoólica, aumentando o rendimento da fermentação em 1,9%.

Fermentation of irradiated sugarcane must

Bacillus and Lactobacillus are bacteria that usually contaminate the ethanolic fermentation by yeasts and may influence yeast viability. As microorganisms can be killed by ionizing radiation, the efficacy of gamma radiation in reducing the population of certain contaminating bacteria from sugarcane must was examined and, as a consequence, the beneficial effect of lethal doses of radiation on some parameters of yeast-based ethanolic fermentation was verified. Must from sugarcane juice was inoculated with bacteria of the genera Bacillus and Lactobacillus. The contaminated must was irradiated with 2.0, 4.0, 6.0, 8.0 and 10.0 kGy of gamma radiation. After ethanolic fermentation by the yeast (Saccharomyces cerevisiae) the total and volatile acidity produced during the process were evaluated; yeast viability and ethanol yield were also recorded. Treatments of gamma radiation reduced the population of the contaminating bacteria in the sugarcane must. The acidity produced during the fermentation decreased as the dose rate of radiation increased. Conversely, the yeast viability increased as the dose rate of radiation increased. Gamma irradiation was an efficient treatment to decontaminate the must and improved its parameters related to ethanolic fermentation, including ethanol yield, which increased 1.9%.

Bactérias dos gêneros Bacillus e Lactobacillus são microrganismos que normalmente contaminam a fermentação alcoólica realizada por leveduras. Estas bactérias podem causar queda da viabilidade das leveduras. Como a radiação ionizante pode eliminar microrganismos, estudou-se o efeito da radiação gama na redução da população de bactérias contaminantes do mosto de caldo de cana-de-açúcar e verificaram-se seus efeitos sobre alguns parâmetros da fermentação alcoólica. O mosto de caldo de cana-de-açúcar foi inoculado contaminado com bactérias dos gêneros Bacillus e Lactobacillus, e após irradiação com doses de 2,0; 4,0; 6,0; 8,0 e 10,0 kGy de radiação gama, foi efetuado a contagem da população das bactérias. Leveduras Saccharomyces cerevisiae foram inoculadas no mosto irradiado para realizarem a fermentação alcoólica. Após a fermentação, foram determinados a acidez total e a acidez volátil do vinho, a viabilidade das células de levedura e o rendimento da fermentação. O tratamento com radiação gama reduziu a população das bactérias contaminantes do mosto. A acidez produzida durante a fermentação diminuiu com o aumento das doses de radiação aplicadas ao mosto, e viabilidade das leveduras aumentou com o aumento das doses de radiação. A irradiação gama foi um eficiente tratamento para descontaminar o mosto de caldo de cana-de-açúcar e melhorar os parâmetros da fermentação alcoólica, aumentando o rendimento da fermentação em 1,9%.

Eliminação ou inativação de fungos do gênero Aspergillus em amendoim (Arachis hypogea, L), e o aumento de sua vida de prateleira, quando tratado com radiação gama / Elimination or inactivation of the fungi genus Aspergillus in peanut (Arachis hypogea, L), and increased its shelf-life when treated with gamma radiation

A presente pesquisa, investigou a eficácia da aplicação da radiação gama para evitar o aparecimento de fungos patogênicos em amendoim (Arachis hypogea, L), conseqüentemente, conferindo ao produto uma melhor qualidade fitossanitária e maior vida de prateleira. Foram pesquisadas amostras processadas salgadas e in-natura. Depois de submetidas à radiação proveniente de uma fonte de césio-137, para absorverem doses de 0; 1,5; 2,0 e/ou 2,5 kGy, as amostras foram monitoradas sensorial e micologicamente e comparadas às testemunhas (não irradiadas). Análises sensoriais periódicas mostraram que o tratamento por irradiação com dose de 2,0 kGy não alterou perceptivelmente o sabor do amendoim in-natura, mas causou uma evidente alteração no sabor das amostras de amendoim processado.(...).(AU)

This work has studied the efficiency of gamma radiation to either delay or prevent the incidence of pathogenic fungi in peanut (Arachis hypogea, L), consequently rendering it a better sanitary quality and longer shelf-life. Samples of natural (non processed) and processed (salty) peanut grains were investigated. After being exposed to gamma radiation supplied by a cesium-137 source, in order to absorb doses of O; 1,5; 2,0 and/or 2,5 kGy, the peanut samples were monitored for changes in flavor and fungi growth and compared to the non-irradiated ones (witnesses). Periodic sensory analyses showed that the irradiation treatment with a 2,0 kGy dose did not produce any noticeablechange in flavor of natural peanut grains, but significantly altered the flavor of processed (salty) peanut. (...)(AU)