ABSTRACT
ABSTRACT: The main problem in anaerobic digestion of low-protein residues is the instability caused acidity. The use of limestone at the same time as a neutralizing agent and support material is innovative because stones wear allows the slow release of the calcium carbonate thereby eliminating dispersers. Free calcium content in the system was measured in two plug flow reactors filled with vinasse at initial pH of 4.50. The proportion of 1.8 tonnes of limestone per m³ of vinasse was evaluated at the Hydraulic Retention Times (HRT) of 24, 48, 72, 96 and 120 hours, allowing stabilisation at 96 hours. The ratio of Volatile Acids/Total Alkalinity (VA/TA) ranged from 0.2 to 0.4 and the pH reached 7.0, at the HRT of 120 hours. Increasing the HRT also increased the volatile total solids (VTS) and fixed total solids (TFS) in a similar profile to the measured free calcium content, but calcium remained at the appropriate level of 100 to 250mg l-1. The proportion of limestone/vinasse was adequate to ensure stabilisation, but it is not recommended to reduce the HRT below 96 hours due to the risk of compromising the stability of the anaerobic system.
RESUMO: O maior problema na digestão anaeróbia de resíduos de baixo teor de proteína é a instabilidade por acidez. O uso de calcário ao mesmo tempo como agente neutralizador e material suporte é inovador porque permite eliminar o dosador pois o desgaste das pedras permite a liberação lenta do carbonato de cálcio. O teor de cálcio livre no sistema foi medido em dois reatores tipo Plug flow, preenchidos com vinhaça com pH inicial de 4,50. A proporção de 1,8 toneladas de calcário por m³ de vinhaça foi avaliada com os Tempos de Retenção Hidráulica (TRH) de 24, 48, 72, 96 e 120 horas, permitindo a estabilização em 96 horas. Com um TRH de 120 horas, a relação de Ácidos Voláteis/Alcalinidade (AV/AC) variou de 0,2 à 0,4 e o pH atingiu 7,0. Aumentando o TRH também aumentaram os sólidos voláteis totais (SVT) e sólidos totais fixos (STF) em um perfil semelhante ao teor de cálcio livre medido, mas mantendo níveis adequados de 100 a 250mg L-1. A proporção de calcário/vinhaça mostrou-se adequada para garantir a estabilização, mas não se recomenda a redução do TRH abaixo de 96 horas devido ao risco de comprometer a estabilidade do sistema anaeróbio.
ABSTRACT
ABSTRACT In Brazil, ethanol is obtained by fermentat of sugar cane juice using Saccharomyces cerevisiae. The cane juice extraction generates the bagasse that has been used for obtaining generation biofuel. However, the sugarcane bagasse has 30% pentose that cannot be fermented to ethanol by S. cerevisiae. Thus the aim of this study was to isolate a yeast able to ferment xylose to ethanol. Samples of cane juice and flowers were used for the isolation of 165 strains that were then screened for ethanol production using plate testing. Among them, the ethanol positive strains Wickerhamomyces anomalus, Schizosaccharomyces pombe and Starmerella meliponinorum were selected for a xylose fermentation assay, using a semi-synthetic and bagasse hydrolysate as must. S. meliponinorum and S. pombe produced 0.63 and 2.7 gL-1 of ethanol, respectively, from xylose in a semisynthetic medium. In the medium consisting of bagasse hydrolysate must, 0.67 and 1.1 gL-1 of ethanol were obtained from S. meliponinorum and S. pombe, respectively. All the yeasts produced xylitol from xylose in the semisynthetic medium and S. meliponinorum was that which produced the highest quantity (14.5 g L-1).
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This study aimed to explore the variability in the metabolism of nine wild yeasts isolated from the sugarcane juice from a distillery in the Brazilian State of Mato Grosso. Cell viability under the stress conditions was evaluated. The yeasts were inoculated in the test tubes containing sugarcane juice adjusted from 12 to 21º Brix, ethanol from 6 to 12% in volume and temperature at 30, 35 and 40ºC. The viability was established by the growth in Petri dishes and visually by the CO2 production in the test tubes. None of the evaluated yeasts showed simultaneous resistance to the three stress conditions. The potential of yeast BB.09 could be emphasized due to its ability to ferment up to12% ethanol at 30°C.
ABSTRACT
In this work, the effect of lactic acid and UV irradiation on the physicochemical and structural characteristics of cassava and corn starches was evaluated. Only the modified cassava starch presented baking expansion capacity. From RVA, reduction of viscosity values, greater internal stability and none set back for modified cassava starch were observed. Modified corn starch did not show any peak viscosity. There were no significant differences in DSC thermal properties of treated and native starches. Amylopectin and amylose molecules from both the modified starches displayed some degradation. Molecular weight of cassava amylopectin was mostly preserved, whereas corn amylopectin was evenly attacked through the granule. Nevertheless, the B long branched chains of cassava amylopectin, with DP~37, were degraded whereas they were unchanged for corn amylopectin.
Amido de mandioca modificado com ácido lático e radiação ultravioleta antes da secagem artificial têm mostrado boa capacidade de expansão, a exemplo da encontrada para o polvilho azedo. Neste trabalho, os efeitos do ácido lático e radiação UV sobre as características físico-químicas e estruturais de amidos de mandioca e milho foram investigados. Apenas o amido de mandioca modificado apresentou capacidade de expansão durante o forneamento. Do RVA, redução dos valores de viscosidade, boa estabilidade interna e nenhuma tendência a retrogradação para este amido modificado foi observado. O amido de milho não apresentou qualquer pico de viscosidade após modificação. Não foram observadas diferenças significativas nas propriedades térmicas, determinadas em DSC, entre os amidos nativos e modificados de ambas as fontes. As moléculas de amilopectina e amilose de ambos os amidos modificados mostraram alguma degradação. O peso molecular da amilopectina do amido de mandioca foi mais preservado, enquanto a amilopectina do amido de milho foi mais atacada em todo o grânulo. As cadeias ramificadas longas da amilopectina de mandioca, com DP~37, foram degradadas, enquanto as de milho mantiveram-se inalteradas.
ABSTRACT
The wastewater of the processing of cassava's flour (manipueira) was submitted to the anaerobic treatment in two phases: acidogenic and methanogenic. In the acidogenic phase, the wastewater was stabilized with NaOH (ASH) and with limestone (ASL). After that, both stabilized effluents were treated by a methanogenic reactor. Then, the effluent of the methanogenic reactor was used as fertilizer on maize in the initial growth stage (30 days), cultivated in pots in a greenhouse. The treatments were T1: control without urea addition (only N from soil); T2: NPK (2.2 g of urea with 45 percent of N); T3: ASH (84 mL.kg soil-1); T4: ASL (102 mL.kg soil-1); T5: double dose ASH (168 mL.kg soil-1) and T6: double dose ASL (204 mL.kg soil-1). Each treatment was composed by 4 plants/pot in five repetitions. It was observed that all the treatments with stabilized wastewater had favorable effect to the soil pH (> than 7.5) and basis saturation (V percent) in the soil around to 90 percent. The performances of nitrogen absorption by the maize plants were 64, 54, 80 and 78 percent for T3, T4, T5 and T6, respectively.
A água residuária do processamento de farinha de mandioca (manipueira) foi submetida ao tratamento anaeróbio em duas fases: acidogênica e metanogênica. Na fase acidogênica, a água residuária foi estabilizada com NaOH (ASH) e com calcário (ASL). Em seguida, ambos efluentes estabilizados foram tratados por um reator metanogênico. Então, o efluente do reator metanogênico foi usado como fertilizante no milho no estádio inicial de crescimento (30 dias) cultivado em vaso em casa de vegetação. Os tratamentos foram T1: controle sem uréia (somente N do solo); T2: NPK (2,2 g de uréia com 45 por cento de N); T3: ASH (84 mL.kg solo-1); T4: ASL (102 mL.kg solo-1); T5: dose dupla de ASH (168 mL.kg solo-1) e T6: dose dupla de ASL (204 mL.kg solo-1). Cada tratamento foi composto por 4 plantas/vaso com 5 repetições. Foi observado que todos os tratamentos com á água residuária estabilizada tiveram efeitos favoráveis ao pH do solo (> que 7,5) e saturação de bases (V por cento) no solo ao redor de 90 por cento. A eficiência de absorção de nitrogênio pelas plantas foram 64 por cento, 54 por cento, 80 por cento e 78 por cento para T3, T4, T5 e T6, respectivamente.
ABSTRACT
PURPOSE: To evaluate the antitumor effect of acetone cyanohydrin in Ehrlich ascites tumor cells in vitro. METHODS: The Ehrlich ascites tumor cells and lymphocytes were incubated with different concentrations of acetone cyanohydrin (0, 0.5, 1.0, 2.0, 10.0, 20.0 and 30.0 μg.mL-1), After 1, 2, 3, 4, 18 and 24 hours cell viability tests were performed by the trypan blue method. RESULTS: The results demonstrated a dose-dependent cytotoxic effect against the cells of Ehrlich ascites tumor. The concentrations of 20 and 30 μg.mL-1 was 100 percent of cell death in only 1 and 2 hours respectively. In lower doses of 0.5, 1.0 and 2.0 μg.mL-1 the cytotoxic effect was less intense, increasing gradually with time. CONCLUSIONS: At low concentrations of 0.5, 1.0 and 2.0 μg.mL-1, more than 90 percent of cell death was observed only after 24 hours of incubation which is the evidence that the tumor cell has the ability to poison cumulatively and irreversibly itself with the acetone cyanohydrin when compared with the results presented by human lymphocytes that the same doses and at the same time of incubation reached a maximum of 30 percent of cell death, suggesting an activity of rhodanese differentiated between the two cells.
OBJETIVO: Avaliar o efeito antitumoral da acetona cinidrina em células do tumor ascítico de Ehrlich in vitro. MÉTODOS: Células do tumor ascítico de Ehrlich e linfócitos foram incubadas com diferentes concentrações de acetona cianidrina (0, 0,5, 1,0, 2,0, 10,0, 20,0 e 30,0 μg.mL-1), depois de 1, 2, 3, 4, 18 e 24 horas foi verificada a viabilidade celular atravéz do método de azul de trypan. RESULTADOS: Os resultados demonstraram um efeito citotóxico dose dependente frente as células do tumor ascítico de Ehrlich. Nas concentrações de 20 e 30 μg.mL-1 ocorreu 100 por cento de morte celular em apenas 1 e 2 horas respectivamente. Nas doses mais baixas de 0,5, 1,0 e 2,0 μg.mL-1 o efeito citotóxico foi menos intenso, aumentando gradativamente com o tempo. CONCLUSÕES: Nas concentrações baixas de 0,5. 1,0 e 2,0 μg.mL-1, foi observado mais de 90 por cento de morte celular somente após 24 horas de incubação o que evidência a capacidade da célula tumoral de se intoxicar de maneira irreversível e acumulativa com a acetona cianidrina, quando comparadas com os resultados apresentados pelos linfócitos humanos que nas mesmas doses e nos mesmos tempos de incubação atingiram um máximo de 30 por cento de morte celular, o que sugere uma atividade de rodanase diferenciada entre as duas células.
Subject(s)
Adult , Animals , Humans , Male , Mice , Young Adult , Antineoplastic Agents/therapeutic use , Carcinoma, Ehrlich Tumor/drug therapy , Nitriles/therapeutic use , Analysis of Variance , Cell Survival/drug effects , Young AdultABSTRACT
The influence of additives (sucrose, propylene glycol and soybean oil) and process parameters (pH and temperature), on bio-based cassava starch-gelatin films stability during storage have been evaluated factorial experiment design. X-ray diffractograms have indicated that only sucrose influenced film stability resulting in crystallization during storage (60 days), which was also observed by scanning electron and light microscopy images. Light micrographs, besides indicated sucrose crystallization, also allowed observing phase separation. All biofilm samples presented a high lightness and low redness and yellowness, indicating to be almost colorless. Although temperature did not influence film microstructure and color, casting temperature of 60ºC had completely destroyed samples, and it has not been recommended for further investigations.
Subject(s)
Biofilms , Color , Crystallization , Food Additives , Food Storage , Food TechnologyABSTRACT
Com o objetivo de verificar a qualidade protéica da folha desidratada de mandioca (Manihot esculenta Crantz) foi realizado um ensaio biológico, de 25 dias com 8 tratamentos e 8 animais cada um. Ao final do experimento todos os animais foram sacrificados e as carcaças e as fezes analisadas. O consumo de alimento e o peso dos animais foram controlados. Foi verificado através dos índices, coeficiente de eficácia alimentar (CEA), razão protéica líquida (NPR), coeficiente de digestibilidade verdadeira (CDv), utilização da proteína líquida verdadeira (NPU) e valor biológico (VB) que a qualidade protéica da folha foi inferior à caseína...
Subject(s)
Animals , Rats , Chemical Phenomena , Manihot , Plant Leaves , Proteins , Caseins , EatingABSTRACT
Sour starch pr "polvilho azedo", a sun-dried fermented cassava starch, is widely known in Brazil as an important cooking ingredient, mainly for biscuit for making. As the process arose from popular knowledge all over the country, it is possible to found different ways of production, nowadays focused in the Southeast and Southern States. The standard of quality of sour starch is not yet clearly defined and empirical quality tools are used in order to manage the production process and to commercialize the product. The economical possibilities qhich arise with the opening of the frontiers for exportation process in South America MERCOSUL strongly recommended further studies in this area. In the present study 31 samples of sour starch were collected in Paraná for investigations concerning sanitary conditions and physical, chemical and functional properties. In almosta all samples it was detected foreign bodies including insects, acarides, rodent's hair and sandy material. The results concerning physical, chemical and functional properties stated medium, minimum and maximum values as well as the range of values at 95 per cent confidence. Compared to the properties of natural cassava starch, overlapping was observed in water content and in water binding capacity. The properties that could be used to discriminate the natural and fermented starch are pH, acidity, solubility of the granules, and specific volume and degree of expansion of the biscuit. Further statistical analysis showed no correlation among the properties, and the results were not useful to discriminate clusters of similarity. As the degree of expansion and specific volume of the biscuit are suitable indicator of quality, both properties can be used to manage the quality of the product and of the process