Michaelsen Lindegaard (bottomwinter97)

Considering importance and several industrial applications of lysozyme, including natural antibiotic and preservative, identifier for the diagnosis of diseases, and extraction purposes, its reversibility and stability studies can be very important. In this paper, the role that buffer and osmolytes concentrations play on the thermodynamic stability of lysozyme denaturation process, that is a new simple and inexpensive method, was evaluated by Nano-DSC III, far- and near-UV CD and fluorescence techniques. In thermal denaturation study, RI and ΔG of protein increased from 25.62% to 58.82% and 48.87 to 63.63 kJ mol-1 with the increment of buffer and osmolytes concentrations, respectively. These changes showed a significant increase of 129.59% in RI and 28.16% in ΔG. The effect of buffer and osmolytes concentrations on the secondary and tertiary structures of protein was also investigated. The results indicated that increment of buffer and osmolytes concentrations increase rigidity and thermodynamic stability of protein. Also, structure of protein may be changed by its interaction with GNPs. Hence, interaction of lysozyme with GNPs was studied at the buffer and osmolytes concentrations that gives the maximum RI and ΔG, respectively. The results showed that molten globule-like state was formed by lysozyme in the presence of GNPs.The statistical physics approach has been well studied by our research team for liquid and gaseous adsorption systems. This treatment is based on the grand canonical partition function to give new interpretations of the adsorption process at molecular level for chemical senses olfaction and taste. This work represents a contribution to understand the olfaction mechanism of four of enantiomeric terpenes by applying a statistical physics treatment that allows giving a physico-chemical meaning to parameters involved in the analytical model. It is possible to estimate the number of adsorbed molecules per site, the anchorage number, the receptor density, the concentration at half saturation and the molar adsorption energy. Through this selection of the best fitting model and through fitted values of these parameters, we showed that the adsorption of carvone and limonene enantiomers is not a multilayer process but a monolayer monosite process (monolayer adsorption model with identical and independent sites (n ≠ 1)). The physico-chemical model parameters can be used for the energetic characterization of the interactions between the carvone and the limonene enantiomers and the human olfactory receptor OR1A1 and the determination of an olfactory band of order of 14 kJ/mol, 7 kJ/mol, 9 kJ/mol, 8 kJ/mol for (R)-(-)-carvone, (S)-(+)-carvone, (R)-(+)-limonene and (S)-(-)-limonene, respectively, through the determination of the adsorption energy values and the adsorption energy distributions (AEDs). Thanks to the grand canonical formalism in statistical physics, the negative values of the Gibbs free enthalpy indicate that the adsorption process of the four enantiomeric terpenes onto the human olfactory receptor OR1A1 was spontaneous. The exothermic adsorption mechanism involved in the olfactory perception was explained via the negative values of the internal energy.Despite numerous applications of nanofibrous alginate (Alg) mat, its facile fabrication via electrospinning is still challenging. The low alginate content compared to the carrier polymer and existence of impurities are the main drawbacks of existing approaches. The purpose of this research is both to study and improve alginate electrospinnability by focusing on the effect of inter- and intramolecular hydrogen bonding. Based on hard and soft acids and bases (HSAB) theory, the Na+ cations (carboxylate counter-cation) were substituted with a harder acid, Li+ cation, to increase the strength of ionic interaction and decrease the density of hydrogen bonding. Viscosity and electrical conductivity measurements as wel