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Clove bud essential oil, extracts from ginger, pimento and black pepper, or ascorbyl palmytate were studied as natural antioxidants for the inhibition of autooxidation of polyunsaturated fatty acids in linseed oil. Different methods were used to estimate antioxidant efficiency. These methods are based on the following parameters: peroxide values; peroxide concentration; content of degradation products of unsaturated fatty acid peroxides, which acted with thiobarbituric acid; diene conjugate content; the content of volatile compounds that formed as products of unsaturated fatty acid peroxide degradation; and the composition of methyl esters of fatty acids in samples of oxidized linseed oil.

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The combination of data obtained from isothermal mixing calorimetry and light scattering allowed us to reveal the relationships between the character of the interactions of casein (ß-casein and sodium caseinate (SCN) particles) with phosphatidylcholine (PC) liposomes and their specific properties, such as, the hydrophilic-lipophilic balance of the surface properties, the size, and the architecture. The size distribution diagrams, obtained by dynamic light scattering for the particles of pure PC, ß-casein and their complexes, indicated the involvement of both the protein and liposome particles in the complex formation at pH 5.5 and low ionic strength (0.001 M). As this took place, the data of the extraction of the free PC from the aqueous solutions of the complex particles by diethyl ether showed about 90% of the binding of the PC liposomes by the ß-casein particles. As a result of the interactions, the complex particles showed markedly higher values of their density, calculated on the basis of the light scattering data, as compared to the ones, which were inherent to the pure protein particles. The generality of the importance of such a structural parameter as the density of the complex (protein + PC) particles for their function as protectors against oxidation for the unsaturated PC was supported by the data obtained for the complex particles formed between SCN and PC liposomes at pH 5.5, 40 °C and the low ionic strength (0.001 M). In addition, the importance of both the density and the architecture of the complex (protein + PC) particles for their susceptibility to the proteolysis in the gastrointestinal tract was illustrated by the example of the proteolysis of the complex (ß-casein + PC) particles in the simulated gastrointestinal conditions in vitro.

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The sodium caseinate (SCN)-maltodextrin (MD) covalent conjugates were prepared by a food-grade process involving the first step of the Maillard reaction. The covalent conjugates were prepared with different weight ratios of biopolymers (R(MD : SCN) = 0.4; 1; 2; 5) in the system using maltodextrins of strongly different dextrose equivalents (DE), i.e., DE = 2 and 10. We have observed that the covalent conjugation of SCN with MD, in contrast to their simple mixing, improved the protein solubility in an aqueous medium in a wide pH range that was more pronounced in the vicinity of the SCN isoelectric point (pH 3.8-4.4). The extent of SCN solubility was mainly governed by the weight/molar ratio of the biopolymers in the covalent conjugates, R(MD : SCN). Data of static multiangle laser light scattering showed that the revealed increase in the solubility of the conjugates could be predominantly attributable to the dramatic increase in their thermodynamic affinity for an aqueous medium. Which was most pronounced for the maltodextrin with the higher DE (DE = 10). The direct relationship between the increase in the solubility of the conjugates and the increase in their foaming ability, as compared against SCN, has been revealed as a rule both at neutral pH and at the pI. In addition, the found improvement in the protein foaming ability was also defined by both the weight/molar ratio (R(MD : SCN)) and the dextrose equivalent of the maltodextrins attached to the protein.

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Animals with active and passive strategies of adaptive behavior were selected from a population of Wistar rats by testing in a T maze to measure the indexes of behavioral passivity and behavioral activity. After single (stress) or two (stress-restress) water immersions, individual changes in adaptive behavior were used to study the development of post-stress psychopathology and its interaction with the initial behavioral strategy. In the unavoidable aversive environment, active and passive rats developed different types of post-stress depression, only passive individuals fulfilling the criteria of post-traumatic stress disorder.

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The role of corticosteroid hormones in post-stress depression progress and their usage for correction of this psychopathology was studied in active and passive Wistar rats. It was found that only passive individuals had sensitivity to corticosteroids and, among them, only adrenal gland hormones lead to corrections of post-stress depression.

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Animals with active and passive behavioral strategy were selected among male Wistar rats by testing them in the T-maze. Using the results of rats testing in T-maze index of behavioral activity and index of behavioral passivity were calculated. The development of post-stress psychopathology and ils correlation with initial behavioral strategy were studied under water-immersion stress conditions consiclering individual alteration of adaptive behavior. Two paradigms were used--one time trial (stress) and two times trial (stress-restress). It was found that active and passive rats being subjected to inescapable aversive exposure develop different types of post-stress depression and only passive animals show the signs of posttraumatic stress disorder.

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Original behavioral strategy is an important prerequisite for the pathogenesis of post-stress psychopathologies. Heterogeneity of these pathologies depends on the functional activity of hypophyseal-adrenocortical system.

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A single intranasal injection of CRH alters adaptive behavior only in active rats. In particular this procedure results in increase of their behavioral passivity and reduction of psychomotor responsiveness. This neurohormone causes the same effect in active rats being injected by means of the same routine 20 days after animals have been exposed to a single water-immersion stress. But this effect of CHR is not observed after injection of the neurohormone to depressed animals in the stress-restress paradigm. Passive rats, intact or depressed, do not show any behavioral changes, while active ones develop signs of depression after repeated CRH intranasal injection.

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We report on the effect of potato maltodextrins with variable dextrose equivalent (Paselli SA-2, SA-6 and SA-10) on the surface behavior at the air-water interface of the mixture: legumin+small-molecule surfactant. Distinct in nature small-molecule surfactants (model: sodium salt of capric acid, Na-caprate; and commercially important: a citric acid ester of monoglyceride, CITREM) have been under our consideration. The role of the structure of both of the maltodextrins and the small-molecule surfactants in the effect studied has been elucidated by measurements in a bulk aqueous medium of the enthalpy of their interaction from mixing calorimetry, value of weight average molecular weight of the maltodextrins and the thermodynamics of the pair maltodextrin-solvent and maltodextrin-protein interactions from laser static light scattering. The combined data of mixing calorimetry and light scattering suggest some complex formation between the small-molecule surfactants and the maltodextrins. Predominantly hydrophobic interactions along with hydrogen bonding form the basis of the complexes. The effect of the maltodextrins on the thermodynamics of the protein heat denaturation and thereby on the protein conformational stability in the presence of the small-molecule surfactants has been studied by differential scanning calorimetry. The interrelation between the thermodynamics of intermolecular interactions in a bulk and the surface behavior at the planar air-water interface of the ternary systems (maltodextrin+legumin+small-molecule surfactant) has been elucidated by tensiometry. The effect of the maltodextrins on the surface activity of mixtures of legumin with the small-molecule surfactants is governed by the competitive in relation to the protein interactions with the small-molecule surfactants and a subsequent change in the thermodynamic properties of the both biopolymers, which are favorable to the ternary complex formation.

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We report on the effect of distinct in nature small-molecule surfactants (model, a sodium salt of capric acid, Na-caprate; and commercially important, a citric acid ester of monoglyceride, CITREM; a sodium salt of stearol-lactoyl lactic acid, SSL (Na(+)); polyglycerol ester, PGE (080)) on molecular properties in a bulk and at the air-water interface of globular legumin and random-coiled micellar sodium caseinate. The role of the structure of both proteins and small-molecule surfactants in the effect studied has been elucidated by measurements in a bulk aqueous medium of the enthalpy of their interaction from mixing calorimetry, the change in value of weight average molecular weight of the proteins and the thermodynamics of the pair protein-protein interactions from laser static light scattering as well as, in addition, by measurements of the change in hydrodynamic radius for micellar sodium caseinate from laser dynamic light scattering. The effect of the small-molecule surfactants on the thermodynamics of the protein heat denaturation and thereby on the protein conformational stability has been studied by differential scanning calorimetry in the case of globular legumin. The interrelation between the effects of the small-molecule surfactants on the properties of the proteins in a bulk and at the planar air-water interface has been elucidated by tensiometry. The combined data of mixing calorimetry, differential scanning calorimetry and laser light scattering suggest some complex formation between the small-molecule surfactants and the proteins in a bulk aqueous medium. Predominantly hydrophobic interaction along with electrostatic and hydrogen bonding form the basis of the complex formation. The found effect of the small-molecule surfactants on the surface activity of their mixtures with proteins is governed primarily by both the extent of the protein association, resulting in specific hydrophobicity/hydrophilicity of the surface of the protein associates, and the specific protein conformational stability, for the globular protein, produced by the interaction between the proteins and the small-molecule surfactants.