Rosa platyacantha Schrenk from Kazakhstan—Natural Source of Bioactive Compounds with Cosmetic Significance

Plants belonging to the Rosa genus are known for their high content of bioactive molecules and broad spectrum of healing and cosmetic activities. Rosa platyacantha Schrenk is a wild-type species abundant in the mountainous regions of Kazakhstan. The phytochemical composition as well as the bioactivity of R. platyacantha extracts have not been fully investigated to date. In this study, various parts of R. platyacantha plant, collected in Almaty region, Kazakhstan, were used to prepare five hydroalcoholic extracts (R1–R5). The extracts were compared for the content of phytochemicals and selected biological activities, which are important for the potential cosmetic application of R. platyacantha. Extract R3, prepared from flower buds, showed the most significant antioxidant and tyrosinase inhibitory potential, decreasing the monophenolase and diphenolase activities of tyrosinase. Extract R3 showed also collagenase inhibitory activity and cytotoxicity against human melanoma cells A375, being less cytotoxic for noncancerous skin keratinocytes HaCaT. Analysis of fractions E and F, obtained from R3 extracts, revealed that quercetin, kaempferol, rutin, and their derivatives are more likely responsible for the tyrosinase inhibitory properties of R. platyacantha extracts.     

Is Phytomelatonin Complex Better Than Synthetic Melatonin? The Assessment of the Antiradical and Anti-Inflammatory Properties

This work aims to assess the recently established anti-inflammatory and antioxidant potential of melatonin of plant origin extracted from the plant matrix as a phytomelatonin complex (PHT-MLT), and compare its activity with synthetic melatonin (SNT-MLT) when used on its own or with vitamin C. For this purpose, a COX-2 enzyme inhibitory activity test, an antiradical activity in vitro and on cell lines assays, was performed on both PHT-MLT and SNT-MLT products. COX-2 inhibitory activity of PHT-MLT was found to be ca. 6.5 times stronger than that of SNT-MLT (43.3% and 6.7% enzyme inhibition, equivalent to the activity of acetylsalicylic acid in conc. 30.3 ± 0.2 and 12.0 ± 0.3 mg/mL, respectively). Higher antiradical potential and COX-2 inhibitory properties of PHT-MLT could be explained by the presence of additional naturally occurring constituents in alfalfa, chlorella, and rice, which were clearly visible on the HPLC-ESI-QTOF-MS fingerprint. The antiradical properties of PHT-MLT determined in the DPPH test (IC₅₀ of 21.6 ± 1 mg of powder/mL) were found to originate from the presence of other metabolites in the 50% EtOH extract while SNT-MLT was found to be inactive under the applied testing conditions. However, the antioxidant studies on HaCaT keratinocytes stimulated with H₂O₂ revealed a noticeable activity in all samples. The presence of PHT-MLT (12.5, 25 and 50 µg/mL) and vitamin C (12.5, 25 and 50 µg/mL) in the H₂O₂-pretreated HaCaT keratinocytes protected the cells from generating reactive oxygen species. This observation confirms that MLT-containing samples affect the intracellular production of enzymes and neutralize the free radicals. Presented results indicated that MLT-containing products in combination with Vitamin C dosage are worth to be considered as a preventive alternative in the therapy of various diseases in the etiopathogenesis, of which radical and inflammatory mechanisms play an important role.     

Ultrabright Terbium Nanoparticles for FRET Biosensing and in Situ Imaging of Epidermal Growth Factor Receptors**

Lanthanide-doped nanoparticles (LnNPs) have become an important class of fluorophores for advanced biosensing and bioimaging. LnNPs that are photosensitized by surface-attached antenna ligands can possess exceptional brightness. However, their functional bioconjugation remains an important challenge for their translation into bioanalytical applications. To solve this problem, we designed a ligand that can be simultaneously applied as efficient light harvesting antenna for Tb surface ions and strong linker of biomolecules to the LnNPs surfaces. To demonstrate generic applicability of the photosensitized TbNP-bioconjugates, we applied them in two prototypical applications for biosensing and bioimaging. First, in-solution biorecognition was shown by time-resolved Förster resonance energy transfer (FRET) between streptavidin-functionalized TbNPs to biotinylated dyes (ATTO 610). Second, in situ detection of ligand–receptor binding on cells was accomplished with TbNP-antibody (Matuzumab) conjugates that could specifically bind to transmembrane epidermal growth factor receptors (EGFR). High specificity and sensitivity were demonstrated by time-gated imaging of EGFR on both strongly (A431) and weakly (HeLa and Cos7) EGFR-expressing cell lines, whereas non-expressing cell lines (NIH3T3) and EGFR-passivated A431 cells did not show any signals. Despite the relatively large size of TbNP-antibody conjugates, they could be internalized by A431 cells upon binding to extracellular EGFR, which showed their potential as bright and stable luminescence markers for intracellular signaling.     

Kinetics and Products of Air Plasma Induced Oxidation in Water of Imidacloprid and Thiamethoxam Treated Individually and in Mixture

Imidacloprid (I) and thiamethoxam (T) are widely used neonicotinoid insecticides with high persistence in the environment and thus included in the watch list of substances for European Union-wide monitoring reported in the Decision 2015/495/EU. In this work aqueous solutions of I, T and I?+?T were subjected to advanced oxidation by air plasma produced by negative DC corona discharges above the liquid surface. The oxidative degradation of each pollutant was investigated by monitoring the rate and the products of its decay when treated alone and in the presence of variable amounts of the other compound. The results show that both I and T are readily degraded and that mineralization can be achieved in this process, as proven by the measurement of the residual organic carbon and by the quantitative conversion of chlorine and sulfur into inorganic chloride and sulfate, respectively. The major organic intermediates formed during the complex stepwise oxidation of I and T were identified and monitored by HPLC–MS/MS analysis. The results of kinetic studies show that both for I and T the reaction rate depends inversely on the insecticide initial concentration, that I and T have similar reactivities and that they do not interfere reciprocally in any specific way when treated in mixture at a total concentration of ca 1?×?10^?4 M. Based on literature data and on previous results with the same reactor, it is reasonable to propose that the oxidation of I and T is initiated by the reaction with OH radicals.

     

Effects of Fructose and Oligofructose Addition on Milk Fermentation Using Novel Lactobacillus Cultures to Obtain High-Quality Yogurt-like Products

The incorporation of prebiotics in fermented milk products is one of the best ways to promote health benefits while improving their sensory characteristics at the same time. The aim of this study was to evaluate the effects of the addition of fructose and oligofructose (1% and 2%) on the physicochemical, rheological, sensory, and microbiological quality attributes of fermented milk products inoculated with indigenous probiotic starter cultures of Lactobacillus isolated from Polish traditional fermented foods. The samples were evaluated during 35 days of refrigerated storage. The oligofructose and fructose caused increases in the populations of bacteria in comparison to the control fermented milk products without the addition of saccharides. The degrees of acidification in different fermented milk samples, as well as their viscosity, firmness, syneresis, and color attributes, changed during storage. The highest overall sensory quality levels were observed for the samples supplemented with L. brevis B1 and oligofructose. This study is the first attempt to compare the influences of different sugar sources on the physicochemical, rheological, sensory, and microbiological quality attributes of fermented milk products.     

Scale-adaptive simulation of liquid mixing in an agitated vessel equipped with eccentric HE 3 impeller

The current study presents the results of a numerical simulation of hydrodynamics in an agitated vessel equipped with an eccentric HE 3 impeller. CFD (computational fluid dynamics) simulations were carried out using ANSYS 14.0 software. Time-dependent simulations of turbulent flow were carried out using the SAS-SST (scale adaptive simulation-shear stress transport) method coupled with the SM (sliding mesh) method. The results of the calculations are presented as contours of velocity in different cross-sections of the agitated vessel, as well as profiles of components of velocity vector and turbulence kinetic energy and its dissipation rate. The iso-surface of vorticity, which shows the region of possible vortex existence, is also presented. A numerically obtained data set of impeller power number was used to calculate the averaged impeller power number. This value was compared with the experimental data with good results. The relationship between impeller position and fluctuation of the impeller power number was also analysed.     

Silver CD-R based substrate as a SERS active material

A silver Compact Disc Recortable (CD-R) based substrate has been proposed as an alternative to silver colloids as active material successfully used in surface-enhanced Raman spectroscopy (SERS). Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray Spectroscopy (EDXS) measurements revealed that silver nanoparticles are present over the entire surface of the uncovered reflective layer of commonly used CD-R. The process of preparation of the CD-R based surface is simple, fast and repeatable. Recorded Raman spectra of 10 µM Rhodamine 6G applied to the substrate corroborate strong enhancement of Raman signal. The maximum value of EF was calculated to be about 5.76 × 10⁶. Raman maps are consistent with SEM micrographs and confirmed the presence of a numerous SERS hot spots occurring on the trucks of CD-R based substrate.     

The Influence of Surface Composition of Nanoparticles on their Interactions with Serum Albumin

Interactions between differently functionalised silver and gold nanoparticles (NPs) as well as polystyrene nanoparticles with bovine serum albumin (BSA) are studied using circular dichroism (CD) spectroscopy. It is found that the addition of NPs to the protein solution destroys part of the helical secondary structure of the protein as a result of surface adsorption. From the loss of free protein and hence the extent of their structural change adsorption equilibrium constants are derived. The results reveal that citrate‐coated gold and silver NPs exhibit much stronger interactions with BSA than polymeric or polymer‐coated metallic NPs. It is therefore concluded that for the particles considered, the influence of surface composition on the interaction behaviour dominates that of the core.     

The Phenolic Compounds Profile and Cosmeceutical Significance of Two Kazakh Species of Onions: Allium galanthum and A. turkestanicum

Numerous species of Allium genus have been used in the traditional medicine based on their vast biological effects, e.g., antimicrobial, digestion stimulant, anti-sclerotic, soothing, antiradical or wound healing properties. In this work, unpolar and polar extracts from two lesser-investigated species of Allium growing in Kazakhstan, Allium galanthum Kar. & Kir. (AG) and A. turkestanicum Regel. (AT), were studied for their composition and biological effects. In the HPLC-ESI-QTOF-MS/MS analyses of water and alcoholic extracts simple organic acids, flavonoids and their glycosides were found to be the best represented group of secondary metabolites. On the other hand, in the GC-MS analysis diethyl ether, extracts were found to be rich sources of straight-chain hydrocarbons and their alcohols, fatty acids and sterols. The antimicrobial activity assessment showed a lower activity of polar extracts, however, the diethyl ether extract from AT bulbs and AG chives showed the strongest activity against Bacillus subtilis ATCC 6633, B. cereus ATCC 10876, some species of Staphylococcus (S. aureus ATCC 25923 and S. epidermidis ATCC 12228) and all tested Candida species (Candida albicans ATCC 2091, Candida albicans ATCC 10231, Candida glabrata ATCC 90030, Candida krusei ATCC 14243 and Candida parapsilosis ATCC 22019) with a minimum inhibitory concentration of 0.125–0.5 mg/mL. The highest antiradical capacity exhibited diethyl ether extracts from AG bulbs (IC50 = 19274.78 ± 92.11 mg Trolox eq/g of dried extract) in DPPH assay. In ABTS scavenging assay, the highest value of mg Trolox equivalents, 50.85 ± 2.90 was calculated for diethyl ether extract from AT bulbs. The same extract showed the highest inhibition of mushroom tyrosinase (82.65 ± 1.28% of enzyme activity), whereas AG bulb ether extract was the most efficient murine tyrosinase inhibitor (54% of the enzyme activity). The performed tests confirm possible cosmeceutical applications of these plants.     

Health-Promoting Capacities of In Vitro and Cultivated Goji (Lycium chinense Mill.) Fruit and Leaves; Polyphenols,Antimicrobial Activity,Macro- and Microelements and Heavy Metals

There is a growing interest among the public in fruit with a positive impact on human health. Two goji berry cultivars (‘No. 1’ and ‘New Big’) were propagated in vitro, grown in an orchard and then evaluated for macro- and microelements and harmful heavy metals (i.e., Pb, Ni, and Cd). The leaves and fruit were also assessed for nutritional value, polyphenols and the antimicrobial activity of the leaves. ‘New Big’ was characterized by a higher content of macro elements in the leaves (in vitro and orchard) and a higher content of microelements in the fruit. The harmful substances content was below the minimum value. Furthermore, neither the fruit nor the leaves contained cadmium. This study also indicated that leaves had a higher content of polyphenols compared to the fruit. The fruits were characterized by their health-promoting capacities, while the leaves were characterized by their antibacterial activity. Among the Gram-positive bacteria, the most sensitive strain was Bacillus subtilis, and among the Gram-negative bacteria, it was Proteus vulgaris. Taking into consideration the Recommended Daily Allowance (RDA) for minerals, goji berries can be declared to be a source of Cu, Fe, Mn, Zn and P.