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Sao Joao del Rei, Brazil

The Federal University of São João del-Rei is a Brazilian University with headquarters in São João del-Rei, and campuses in other cities of Minas Gerais like Ouro Branco, Divinópolis and Sete Lagoas. Wikipedia.

Mendes A.A.,Federal University of Sao Joao del Rei | Oliveira P.C.,University of Sao Paulo | De Castro H.F.,University of Sao Paulo
Journal of Molecular Catalysis B: Enzymatic | Year: 2012

Lipases have large differences with respect to the source (animal, plant or microbial cells) and the cheapest preparation commercially available is isolated from porcine pancreas. Although it has been used to lesser extent when comparing with microbial lipases, porcine pancreatic lipase (PPL) has high stability and activity in anhydrous media as demonstrated in esterification and transesterification reactions. In addition, studies have recommended the utilization of this lipase preparation for synthetic applications in which stereoselectivity and cost are considered to be critical factors. Therefore, there is a growing interest in applying PPL to produce not only fine chemicals but also commodities. This review focuses on the isolation and purification, structural features, and biochemical properties of PPL. Immobilization techniques which improve its catalytic activity, storage, operational, and thermal-stability properties are briefly discussed. This review also describes the extensive biotechnological applications for PPL. © 2012 Elsevier B.V. Source

Pliego Jr. J.R.,Federal University of Sao Joao del Rei
Theoretical Chemistry Accounts | Year: 2011

A new solvation model, named shells theory of solvation, is proposed. In this approach, the solvent is divided in two regions, the S1 shell, close to the solute and describing specific solute-solvent interactions, and the S2 shell, representing the remain solvent and accounting for the long-range interaction contribution. A simple theoretical equation can be derived which allows the computation of the solvation free energy using two-point thermodynamic integration and configurations generated from molecular dynamics simulation. The discrete/continuum version of this theory provides rigorous theoretical foundations for the popular long-range Born correction and presents a new reliable expression for including this contribution. Further, it converges to the full discrete representation of the solvent when the number of solvent molecules goes to infinity. The method can be easily applied when the solute-solvent interaction (S1 shell) is treated by full quantum mechanics, while the S2 shell is described by a dielectric continuum solvation method. A simple test of the theory was done for solvation of fluoride ion in benzene solution. The S1 shell was composed of the fluoride ion plus 32 benzene molecules, and the interaction with the S2 shell was calculated at Hartree-Fock level with the MINI basis set and using the polarizable continuum model. © 2010 Springer-Verlag. Source

Pliego Jr. J.R.,Federal University of Sao Joao del Rei
Physical Chemistry Chemical Physics | Year: 2011

A new receptor for SN2 transition states, named NPTROL, is proposed. This molecule has a cavity and four hydroxyl groups that are able to interact with ionic SN2 and E2 transition states. Its catalytic effect and selectivity was investigated through high level ab initio calculations using the fluoride ion plus ethyl chloride in DMSO solution as a model system. Calculations at the ONIOM[CCSD(T)/6-311+G(2df,2p):MP2/BASIS1] level of theory and solvent effects, included through a continuum solvation model, indicate that NPTROL is able to catalyze the SN2 pathway and has an inverse effect on the E2 pathway. Inside the NPTROL cavity, the ΔG‡ for the SN2 transition state is 5.00 kcal mol-1 lower than that for E2, and as a consequence this reaction becomes highly selective toward the SN2 product. © 2011 the Owner Societies. Source

Cornelissen T.,Federal University of Sao Joao del Rei
Neotropical Entomology | Year: 2011

Climate change and extreme weather events affect plants and animals and the direct impact of anthropogenic climate change has been documented extensively over the past years. In this review, I address the main consequences of elevated CO2 and O3 concentrations, elevated temperature and changes in rainfall patterns on the interactions between insects and their host plants. Because of their tight relationship with host plants, insect herbivores are expected to suffer direct and indirect effects of climate change through the changes experienced by their host plants, with consequences to population dynamics, community structure and ecosystem functioning. © 2011 Sociedade Entomológica do Brasil. Source

Rossi Jr. R.,Federal University of Sao Joao del Rei
Physics Letters, Section A: General, Atomic and Solid State Physics | Year: 2010

A scheme to control the evolution of any initial state in subspace {| 1 〉 ⊗ | 0 〉, | 0 〉 ⊗ | 1 〉} is presented. The physical system considered is the one of two coupled modes sharing one excitation. The scheme is based on unitary interactions with an auxiliary subsystem, and it can be used to preserve the initial entanglement of the system. A proposal for implementation of the scheme in the context of microwave cavity is presented. © 2010 Elsevier B.V. All rights reserved. Source

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