Evaluation of Cosmetic and Dermatological Properties of Kombucha-Fermented Berry Leaf Extracts Considered to Be By-Products

Leaves of Rubus fruticosus L., Vaccinum myrtillus L., Ribes nigrum L. and Fragaria vesca L. are considered agro-waste of the berry industry, but they can be a rich source of valuable bioactive compounds used in cosmetic industry. In this study, kombucha-fermented and non-fermented extracts were compared in terms of chemical composition and biological activity. Polyphenol compounds were identified by HPLC/DAD/ESI-MS. The antioxidant potential was analyzed by evaluating the scavenging of intracellular free radicals contained in keratinocytes and fibroblasts and by DPPH and ABTS assay, obtaining a higher radical scavenging capacity for the ferments, especially for R. fruticosus and V. myrtillus ferments. Assessment of the cytotoxicity on skin cell lines showed their positive effect on the viability of fibroblasts and keratinocytes (especially for the ferments after 10 days of fermentation). The potential anti-ageing properties were determined by their ability to inhibit the activity of metalloproteinases, obtaining almost 30% inhibition of collagenase and elastase in the case of fermented V. myrtillus. Moreover, when the samples were applied to the skin, the positive effect of ferments on skin hydration and pH was demonstrated, which indicates that kombucha berry leaf extracts may be an innovative cosmetic ingredient.     

The hardening of Portland cement observed by1H spin-lattice relaxation and single-point imaging

The nature of hydration in ordinary Portland cement samples from different Polish factories was investigated by the proton spin-lattice relaxation timeT ₁ and single-point imaging (SPI). The time dependence of the spin-lattice relaxation timeT ₁ shows the usual behavior:T ₁ is constant at the beginning of hydration (the dormant period), then, during the setting process, decreases to the constant value in the hardening period of hydration. However, there are some anomalies inT ₁ connected with the different amount of the mineral components in the cement sample. The unusual behavior of the stretched parameterα, after about 20 h of hydration, is observed and connected with the microcracking of the cement matrix. The 1-D and 2-D SPI images of the cement paste taken at various times of hydration show the distribution of the water throughout the sample and clearly demonstrate the usefulness of SPI in the study of the internal structure of the porous system.     

Application of TOF-SIMS Method in the Study of Wetting the Iron (111) Surface with Promoter Oxides

In the present work, a simplified model of the Fe(111) surface’s promoter-oxide system was investigated in order to experimentally verify the previously proposed and known models concerning the structure and chemical composition of the surfaces of iron nanocrystallites in the ammonia-synthesis catalyst. It was shown that efficient oxygen diffusion from metal oxides to the clean Fe(111) iron surface took place even at temperatures lower than 100 °C. The effective wetting of the iron surface by potassium oxide is possible when the surface is covered with oxygen at temperatures above 250 °C. In the TOF-SIMS spectra of the surface of iron wetted with potassium, an emission of secondary FeOK⁺ ions was observed that implies that potassium atoms are bound to the iron surface atoms through oxygen. As a result of further wetting the iron surface with potassium ions, a heterogeneous surface structure was formed consisting of a thin K₂O layer, next to which there was an iron-oxide phase covered with potassium ions. Only a limited increase in calcium concentration was observed on the Fe(111) iron surface upon sample annealing at up to 350 °C. As a result of wetting the iron surface with calcium ions, an oxide solution of CaO-Fe_xO_y was formed. In the annealing process of the sample containing alumina, only traces of this promoter diffusing to the iron surface were observed. Alumina formed a solution with a passive layer on the iron surface and under the process conditions (350 °C) it did not wet the pure iron (111) surface. The decrease in Fe⁺-ion emission from the Fe-Ca and Fe-Al samples at 350 °C implies a reduction in the oxygen concentration on the sample surface at this temperature.     

Interaction of Carcinogenic Chromium(VI) Oxide,CrO3, with Main Nonenzymatic Cellular Reductants at Physiological Conditions. Electronic Spectra and Magnetic Studies

The interaction of CrO₃ with ascorbic acid, glutathione and cysteine at physiological conditions (pH=7.4, t=37°C) was investigated using spectral (diffuse reflectance spectra) and magnetic methods. The obtained powders appeared to be Cr(III) complexes of the [Cr(A, B)(H₂O)_x]^n- type, where A, B are organic ligands (A-ascorbic acid, B-glutathione or cysteine). The spectral resolution of the bands enhanced with a digital filter method revealed the lowering symmetry effect in the chromium(III) coordination sphere. The comparison of the results obtained for K₂CrO₄ with these studied in the present paper was made.     

Physicochemical properties and thermal behavior of nitrocellulose granules with eutectic mixtures of stabilizers

Journal of Thermal Analysis and Calorimetry - Examinations of two-component mixtures, namely: triphenylamine?+?centralite I (TPA?+?CI) and...     

Influence of barium oxide on glass-forming ability and glass stability of the tellurite–phosphate oxide glasses

Journal of Thermal Analysis and Calorimetry - The effect of BaO content on the glass-forming ability, glass stability and structure of tellurite–phosphate oxide glasses in the...     

Existence and stability of oscillating solutions for a class of delay differential equations

In this paper we study a Hopf bifurcation for a general class of simple delay differential equations with a term that can describe a treatment. Conditions guaranteeing appearance of the Hopf bifurcation as well as stability of arising periodic orbits are proved. Applications of proved theorems to a general version of the logistic equation are presented.     

On families of invariant lines of a Brouwer homeomorphism

ABSTRACT

We present properties of equivalence classes of the codivergency relation defined for a Brouwer homeomorphism for which there exists a family of invariant pairwise disjoint lines covering the plane. In particular, using the codivergency relation we describe the sets of regular and irregular points for such Brouwer homeomorphisms. Moreover, we show that under this assumption the interior of each equivalence class of this relation is invariant and simply connected.     

Selectivity in normal-phase liquid chromatography with binary mobile phase

A simple theoretical approach to normal-phase liquid chromatography with binary mobile phase is presented. In the model used the driving force for the retention is competitive adsorption of solutes and both solvents. A new expression for the separation factor is proposed and discussed. An influence of different parameters on the selectivity is shown. The theoretical concepts are illustrated by the selected experimental data.