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Martins M.L.,Instituto Federal Do Sudeste Of Minas Gerais | Pinto U.M.,Federal University of Ouro Preto | Riedel K.,University of Greifswald | Vanetti M.C.D.,Federal University of Vicosa
Brazilian Journal of Microbiology | Year: 2015

The practice of refrigerating raw milk at the farm has provided a selective advantage for psychrotrophic bacteria that produce heat-stable proteases and lipases causing severe quality problems to the dairy industry. In this work, a protease (AprX) and a lipase (LipM) produced by Pseudomonas fluorescens 041, a highly proteolytic and lipolytic strain isolated from raw milk obtained from a Brazilian farm, have been purified and characterized. Both enzymes were purified as recombinant proteins from Escherichia coli. The AprX metalloprotease exhibited activity in a broad temperature range, including refrigeration, with a maximum activity at 37 °C. It was active in a pH range of 4.0 to 9.0. This protease had maximum activity with the substrates casein and gelatin in the presence of Ca+2. The LipM lipase had a maximum activity at 25 °C and a broad pH optimum ranging from 7.0 to 10. It exhibited the highest activity, in the presence of Ca+2, on substrates with long-chain fatty acid residues. These results confirm the spoilage potential of strain 041 in milk due to, at least in part, these two enzymes. The work highlights the importance of studies of this kind with strains isolated in Brazil, which has a recent history on the implementation of the cold chain at the dairy farm. © 2015, Sociedade Brasileira de Microbiologia. Source


Correa P.C.,Federal University of Vicosa | De Oliveira G.H.H.,Instituto Federal Do Sudeste Of Minas Gerais | Vasconcelos W.L.,Federal University of Minas Gerais | Vargas-Elias G.A.,University of Costa Rica | And 2 more authors.
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2016

The determination of physical properties is an important factor in the design of machinery and the scaling of post-harvest operations. The present study evaluates the influence of the level of roasting and the size of grinding on the physical properties of coffee during storage. The following physical properties were evaluated: true and bulk density, and intergranular porosity. Raw coffee beans (Coffea canephora and Coffea arabica), hulled and dried, were roasted to two different levels: medium light (SCAA#65) and moderately dark (SCAA#45). The beans were then grinded into three different sizes: fine (0.59 mm), medium (0.84 mm) and coarse (1.19 mm). An additional coffee lot was kept whole. Following grinding, samples were stored at two different temperatures (10 and 30 ºC) and analyzed after five different storage durations (0, 30, 60, 120 and 180 days). The medium light roast had higher values for each of the measured physical properties. Finely ground samples had higher true and bulk densities, and porosities. It is concluded that the size of grinding, level of roasting and duration of storage significantly affect the physical properties of coffee. © 2016, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved. Source


Salvio G.M.M.,Federal University of Lavras | Fontes M.A.L.,Federal University of Lavras | Silveira Junior W.J.D.,Federal University of Lavras | Silva H.A.D.,Instituto Federal Do Sudeste Of Minas Gerais
Cerne | Year: 2016

The objective of this study was to evaluate the possible correlations between the socioeconomic development indicators of the municipalities of Minas Gerais, Brazil, and the presence of both sustainable use and full protection conservation areas (CAs). The Human Development Index (HDI) and Gini Index (GI) values were compared between municipalities with and without CAs using the non-parametric Wilcoxon-Mann-Whitney test. The correlations between the HDI and GI of each municipality and its areas occupied by CAs were analyzed using the non-parametric Spearman correlation test. A total of 560 CAs were identified in the 853 municipalities of the state. The HDI values of municipalities with CAs were not significantly different from those of other areas, but significant differences were found in the GI values, which were higher in municipalities with CAs. No significant correlations were found between the HDI of municipalities and their areas occupied by CAs. However, significant correlations were found between the GI and areas occupied by CAs, suggesting that the CAs are associated with greater socioeconomic inequalities. Populations should be included in conservation efforts through programs that benefit these individuals, such as payment for environmental services and other conservation strategies. © 2016, all rights reserved. Source


Da Rocha E.P.,Federal University of Lavras | Da Rocha E.P.,Instituto Federal Do Sudeste Of Minas Gerais | Ramalho T.C.,Federal University of Lavras
Revista Virtual de Quimica | Year: 2016

Currently the opportune diagnosis of cancer has shown a great importance, mainly by decreasing the mortality rate. Among the techniques employed to achieve the diagnosis, spectroscopy has been highlighted for presenting safe and highly accurate diagnoses. The Fluorescence Spectroscopy has become very important in cancer diagnosis, being employed in breast, oral cavity and esophagus cancer testing. The technique employs fluorophore which in many cases have groups capable of carrying out the intramolecular proton transfer in the excited state (ESIPT). These compounds may be used for various molecular targets such as cations, anions and proteins detection, besides the diagnosis of diseases. Spectroscopic probes have an important role in the development of more accurate diagnosing diseases methods, which may influence the treatment and avoid the risks of further surgery and patient death. Source


Baptestin F.M.,Federal University of Vicosa | Correa P.C.,Federal University of Vicosa | De Oliveira G.H.H.,Instituto Federal Do Sudeste Of Minas Gerais | Almeida L.F.J.,Federal University of Vicosa | Vargas-Elias G.A.,University of Costa Rica
Revista Brasileirade Ciencias Agrarias | Year: 2016

The aim of the present study is to model the dehydration process of pineapple slices through infrared drying, as well as to determine the critical moisture content and the critical time to the dehydration process. Pineapple slices were cut 5.0 mm thick and 2.0 cm diameter, and dried by an infrared heating source equipped with a built-in scale at accuracy of 0.001 g, under the temperatures of 50, 60, 70, 80, 90 and 100 °C, until constant weight was reached. Mass variation readings were taken at 1.0 min intervals. The mathematical models met the experimental data. The modified model by Henderson and Pabis best represented the data about the drying process. The higher drying temperature led to higher critical moisture content (from 2.205 to 2.450 kgw kgdm-1) and to decreased critical time (18.00 to 5.99 min). The coefficient of effective diffusion increased due to temperature (2.848 × 10-15 to 1.439 x 10-14). The activation energy of the drying process was 33.632 kJ mol-1. Source

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