Secondary structure and colloidal stability of beta-casein in microheterogeneous water-ethanol solutions

© 2016 Elsevier LtdDynamic light-scattering (DLS), fluorescence spectroscopy (FS) and circular dichroism (CD) techniques were applied to study the influence of alcohol on beta-casein (b-CN) self-association and the secondary structure in a wide range of temperatures and ethanol concentrations. Temperature induced micellization and demicellization transitions of b-CN in water-ethanol solutions are revealed on the basis of the DLS data. The obtained results indicate that the association of b-CN at low and high alcohol concentrations proceeds through different mechanisms. It is suggested that the solvent microheterogeneity independently modulates both the secondary structure and the colloid properties of b-CN

Effects of hydration, lipids, and temperature on the binding of the volatile aroma terpenes by β-lactoglobulin powders

The binding properties of dry proteins are relatively poorly known. Many proteins are present in emulsions and suspensions and also in dry forms. This is particularly true of dairy proteins, which are often stored and sold in powdered form. In the present work, the binding of three terpenes (α-terpinene, γ-terpinene, and terpinolene), which belong to the basic aroma components, and of decane by powdered β-lactoglobulin (BLG) was studied at different hydration levels (0.05-0.40 g of H2O/g of protein) and temperatures (298 and 309.5 K), in the presence or absence of lipids and small concentrations of ethanol. Vapor sorption isotherms were determined for these systems by a static method of headspace gas chromatographic analysis. A cooperative effect of hydrophobic hydration was observed for the binding of aroma terpenes and decane by the solid BLG. The temperature increase from 298 to 309.5 K reduced the observed hydration threshold of BLG by 0.05-0.08 g of H2O/g of protein. Lipids (1.2% w/w) in hydrated BLG gave at least a 2-fold increase in its binding affinity for the hydrocarbons studied, and synergic effects of the hydration and lipid on this affinity were observed

EFFECT OF ENTEROCOCCUS DURANS BACTERIOCIN ON BACTERIAL WILT AGENT

Effect of a bacteriocin produced by Enterococcus durans A5-11 on growth of Ralstonia solanacearum strains and their ability to cause wilt in tomatoes was investigated. Among tested phytopathogenic strains, 33% were sensitive and inhibited as it was shown after spotting bacteriocin on Ralstonia lawns. Minimal inhibitory concentrations and sizes of lysis or inhibition zones varied depending on the strain used for study. The same differences were evidenced for the effect of the bacteriocin on Ralstonia in a liquid medium and when inoculating Lycopersicon esculentum Mill test plants. Treatment of plant roots with the bacteriocin of E. durans A5-11 simultaneously with inoculation with bacteria of a highly susceptible strain R. solanacearum 6189 resulted in diminished number of wilted tomatoes

A biophysical study on the mechanism of interactions of DOX or PTX with α-lactalbumin as a delivery carrier

© 2018, The Author(s). Doxorubicin and paclitaxel, two hydrophobic chemotherapeutic agents, are used in cancer therapies. Presence of hydrophobic patches and a flexible fold could probably make α-Lactalbumin a suitable carrier for hydrophobic drugs. In the present study, a variety of thermodynamic, spectroscopic, computational, and cellular techniques were applied to assess α-lactalbumin potential as a carrier for doxorubicin and paclitaxel. According to isothermal titration calorimetry data, the interaction between α-lactalbumin and doxorubicin or paclitaxel is spontaneous and the K (M−1) value for the interaction of α-lactalbumin and paclitaxel is higher than that for doxorubicin. Differential scanning calorimetry and anisotropy results indicated formation of α-lactalbumin complexes with doxorubicin or paclitaxel. Furthermore, molecular docking and dynamic studies revealed that TRPs are not involved in α-Lac’s interaction with Doxorubicin while TRP 60 interacts with paclitaxel. Based on Pace analysis to determine protein thermal stability, doxorubicin and paclitaxel induced higher and lower thermal stability in α-lactalbumin, respectively. Besides, fluorescence lifetime measurements reflected that the interaction between α-lactalbumin with doxorubicin or paclitaxel was of static nature. Therefore, the authors hypothesized that α-lactalbumin could serve as a carrier for doxorubicin and paclitaxel by reducing cytotoxicity and apoptosis which was demonstrated during our in vitro cell studies

Grammatical gender and linguistic relativity: A systematic review

Many languages assign nouns to a grammatical gender class, such that ‘bed’ might be assigned masculine gender in one language (e.g. Italian) but feminine gender in another (e.g. Spanish). In the context of research assessing the potential for language to influence thought (the linguistic relativity hypothesis), a number of scholars have investigated whether grammatical gender assignment ‘rubs off’ on concepts themselves, such that Italian speakers might conceptualise beds as more masculine than Spanish speakers. We systematically reviewed 43 pieces of empirical research examining grammatical gender and thought, which together tested 5,895 participants. We classified the findings in terms of their support for this hypothesis, and assessed the results against parameters previously identified as potentially influencing outcomes. Overall, we found that support was strongly task- and context-dependent, and rested heavily on outcomes that have clear and equally-viable alternative explanations. We also argue that it remains unclear whether grammatical gender is in fact a useful tool for investigating relativity

Novel possibilities of processing of beta-casein with engineered trypsin

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Secondary structure and colloidal stability of beta-casein in microheterogeneous water-ethanol solutions

© 2016 Elsevier LtdDynamic light-scattering (DLS), fluorescence spectroscopy (FS) and circular dichroism (CD) techniques were applied to study the influence of alcohol on beta-casein (b-CN) self-association and the secondary structure in a wide range of temperatures and ethanol concentrations. Temperature induced micellization and demicellization transitions of b-CN in water-ethanol solutions are revealed on the basis of the DLS data. The obtained results indicate that the association of b-CN at low and high alcohol concentrations proceeds through different mechanisms. It is suggested that the solvent microheterogeneity independently modulates both the secondary structure and the colloid properties of b-CN

Secondary structure and colloidal stability of beta-casein in microheterogeneous water-ethanol solutions

© 2016 Elsevier LtdDynamic light-scattering (DLS), fluorescence spectroscopy (FS) and circular dichroism (CD) techniques were applied to study the influence of alcohol on beta-casein (b-CN) self-association and the secondary structure in a wide range of temperatures and ethanol concentrations. Temperature induced micellization and demicellization transitions of b-CN in water-ethanol solutions are revealed on the basis of the DLS data. The obtained results indicate that the association of b-CN at low and high alcohol concentrations proceeds through different mechanisms. It is suggested that the solvent microheterogeneity independently modulates both the secondary structure and the colloid properties of b-CN