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The objective of this study was to present a comparative analysis of the antimicrobial activity of methanolic leaf extracts from seven Juniperus L. species, together with a tentative analysis of their total flavonoid and o-dihydroxyphenolic acids content. The chemical analyses were performed by colorimetric methods and the antimicrobial activity was assessed via broth microdilution. The studied extracts showed total content of o-dihydroxyphenols in the range of 26 to 34 µg of caffeic acid equivalent/mg DE and total flavonoid content of 13 to 24 µg of quercetin equivalent/mg DE. The sensitivity of Gram-positive bacteria to the studied extracts differed significantly with the following order of activity: J. sabina var. balkanensis > J. communis ‘Laxa’ > J. formosana > J. pinchotii > J. ashei > J. excelsa ≈ J. sibirica. Weak activity was observed for all extracts against Gram-negative bacteria and Candida strains. The analysis of the MBC/MIC ratio showed that the extracts exhibited bactericidal effect against Gram-negative bacteria (MBC/MIC≤4), while bactericidal or bacteriostatic action (MBC/MIC>4) was determined towards Gram-positive bacteria. Moreover, these extracts showed fungicidal (MFC/MIC≤4) or fungistatic effect (MFC/MIC>4). Best antibacterial activity was registered for the J. sabina var. balkanensis leaf extract. The multivariate data analyses were carried out by SIMCA 16 (v16.0.2) software. The hierarchical cluster analysis and principal component analysis, based on phytochemical and antimicrobial data, classified the studied juniper species into four groups: 1. J. ashei; 2. J. excelsa, J. sibirica; 3. J. sabina var. balkanensis, J. communis Laxa, J. formosana; 4. J. pinchotii.

Terpenes are plant secondary metabolites known for their anti-inflammatory and antioxidant activities. According to ethnobotanical knowledge, Rhododendron luteum Sweet was used in traditional medicine against inflammation. The present study was conducted to determine the triterpene profile and antioxidant and anti-inflammatory activity of supercritical CO2 (SC-CO2) extracts of Rhododendron luteum Sweet flower (RLF). An LC-APCI-MS/MS analysis showed the presence of eight pentacyclic triterpenes and one phytosterol in the extracts obtained with pure CO2 as well as CO2 with the addition of aqueous ethanol as a co-solvent. Among the compounds detected, oleanolic/ursolic acid, β-sitosterol and 3β-taraxerol were the most abundant. The extract obtained with pure SC-CO2 was additionally subjected to HS-SPME-GC-FID-MS, which revealed more than 100 volatiles, mainly eugenol, β-phenylethanol, dodecane, β-caryophyllene, estragole and (Z)- and (E)-cinnamyl alcohol, followed by δ-cadinene. The extracts demonstrated significant hyaluronidase inhibition and exhibited varying modes of lipoxygenase and xanthine oxidase inhibitory activities. The studies of RLF have shown that their SC-CO2 extracts can be a rich source of triterpenes with anti-inflammatory potential. [ABSTRACT FROM AUTHOR]

Binary AsxSe100−x alloys from the border of a glass-forming region (65 < x < 70) subjected to nanomilling in dry and dry–wet modes are characterized by the XRPD, micro-Raman scattering (micro-RS) and revised positron annihilation lifetime (PAL) methods complemented by a disproportionality analysis using the quantum–chemical cluster modeling approach. These alloys are examined with respect to tetra-arsenic biselenide As4Se2 stoichiometry, realized in glassy g-As65Se35, glassy–crystalline g/c-As67Se33 and glassy–crystalline g/c-As70Se30. From the XRPD results, the number of rhombohedral As and cubic arsenolite As2O3 phases in As-Se alloys increases after nanomilling, especially in the wet mode realized in a PVP water solution. Nanomilling-driven amorphization and reamorphization transformations in these alloys are identified by an analysis of diffuse peak halos in their XRPD patterning, showing the interplay between the levels of a medium-range structure (disruption of the intermediate-range ordering at the cost of an extended-range one). From the micro-RS spectroscopy results, these alloys are stabilized by molecular thioarsenides As4Sen (n = 3, 4), regardless of their phase composition, remnants of thioarsenide molecules destructed under nanomilling being reincorporated into a glass network undergoing a polyamorphic transition. From the PAL spectroscopy results, volumetric changes in the wet-milled alloys with respect to the dry-milled ones are identified as resulting from a direct conversion of the bound positron–electron (Ps, positronium) states in the positron traps. Ps-hosting holes in the PVP medium appear instead of positron traps, with ~0.36–0.38 ns lifetimes ascribed to multivacancies in the As-Se matrix. The superposition of PAL spectrum peaks and tails for pelletized PVP, unmilled, dry-milled, and dry–wet-milled As-Se samples shows a spectacular smoothly decaying trend. The microstructure scenarios of the spontaneous (under quenching) and activated (under nanomilling) decomposition of principal network clusters in As4Se2-bearing arsenoselenides are recognized. Over-constrained As6·(2/3) ring-like network clusters acting as pre-cursors of the rhombohedral As phase are the main products of this decomposition. Two spontaneous processes for creating thioarsenides with crystalline counterparts explain the location of the glass-forming border in an As-Se system near the As4Se2 composition, while an activated decomposition process for creating layered As2Se3 structures is responsible for the nanomilling-driven molecular-to-network transition. [ABSTRACT FROM AUTHOR]

Berberis vulgaris L. (Berberidaceae) is a shrub that has been widely used in European folk medicine as an anti-inflammatory and antimicrobial agent. The purpose of our study was to elucidate the mechanisms of the chemopreventive action of the plant's methanolic root extract (BVR) against colon cancer cells. Studies were conducted in human colon adenocarcinoma cell lines (LS180 and HT-29) and control colon epithelial CCD841 CoN cells. According to the MTT assay, after 48 h of cell exposure, the IC50 values were as follows: 4.3, 46.1, and 50.2 µg/mL for the LS180, HT-29, and CCD841 CoN cells, respectively, showing the greater sensitivity of the cancer cells to BVR. The Cell Death Detection ELISAPLUS kit demonstrated that BVR induced programmed cell death only against HT-29 cells. Nuclear double staining revealed the great proapoptotic BVR properties in HT-29 cells and subtle effect in LS180 cells. RT-qPCR with the relative quantification method showed significant changes in the expression of genes related to apoptosis in both the LS180 and HT-29 cells. The genes BCL2L1 (126.86–421.43%), BCL2L2 (240–286.02%), CASP3 (177.19–247.83%), and CASP9 (157.99–243.75%) had a significantly elevated expression, while BCL2 (25–52.03%) had a reduced expression compared to the untreated control. Furthermore, in a panel of antioxidant tests, BVR showed positive effects (63.93 ± 0.01, 122.92 ± 0.01, and 220.29 ± 0.02 mg Trolox equivalents (TE)/g in the DPPH•, ABTS•+, and ORAC assays, respectively). In the lipoxygenase (LOX) inhibition test, BVR revealed 62.60 ± 0.87% of enzyme inhibition. The chemical composition of BVR was determined using a UHPLC-UV-CAD-MS/MS analysis and confirmed the presence of several known alkaloids, including berberine, as well as other alkaloids and two derivatives of hydroxycinnamic acid (ferulic and sinapic acid hexosides). The results are very promising and encourage the use of BVR as a comprehensive chemopreventive agent (anti-inflammatory, antioxidant, and pro-apoptotic) in colorectal cancer, and were widely discussed alongside data from the literature. [ABSTRACT FROM AUTHOR]

In this paper, the authors report strain-balanced M-structures InAs/GaSb/AlSb/GaSb superlattice growth on GaSb substrates using two kinds of interfaces (IFs): GaAs-like IFs and InSb-like IFs. The in-plane compressive strain of 60-period and 100-period InAs/GaSb/AlSb/GaSb with different InAs (1) and AlSb (1) monolayers are investigated. The M-structures InAs/GaSb/AlSb/GaSb represent type II superlattices (T2SL) and at present are under intensive investigation. Many authors showtheoretical and experimental results that such structures can be used as a barrier material for a T2SL InAs/GaSb absorber tuned for long-wave infrared detectors (8 µm-14 µm). Beside that, M-structure can also be used as an active material for short-wave infrared detectors to replace InAs/GaSb which, for this region of infrared, are a big challenge from the point of view of balancing compression stress. The study of InAs/GaSb/AlSb/GaSb superlattice with the minimal strain for GaSb substrate can be obtained by a special procedure of molecular beam epitaxy growth through special shutters sequence to form both IFs. The authors were able to achieve smaller minimal mismatches of the lattice constants compared to literature. The high-resolution X-ray diffraction measurements prove that two types of IFs are proper for balancing the strain in such structures. Additionally, the results of Raman spectroscopy, surface analyses of atomic force microscopy, and differential interference contrast microscopy are also presented. The numerical calculations presented in this paper prove that the presence of IFs significantly changes the energy gap in the case of the investigated M-structures. The theoretical results obtained for one of the investigated structures, for a specially designed structure reveal an extra energy level inside the energy gap. Moreover, photoluminescence results obtained for this structure prove the good quality of the synthesized M-structures, as well as are in a good agreement with theoretical calculations. [ABSTRACT FROM AUTHOR]

Replacing the gluten network to produce high quality pasta is a great technological challenge. One of known solutions to the problem is the addition of xanthan gum. This paper focuses on the possibility of obtaining a new type of gluten-free maize-field bean pasta and explores the characteristics of phenolics content, antioxidant activity, cooking quality, textural and thermotropic behavior as well as the microstructure of pasta products with the various levels of added xanthan gum. The obtained results revealed that 0.25, 0.50 and 0.75% addition of xanthan gum to pasta did not have significant influence on its phenolics content and antioxidant activity, whereas 1.00% addition caused a decrease in the tested parameters. On the other hand, the opposite effect of gum addition on the cooking quality, texture characteristic and microstructure was observed. The addition of xanthan gum to the formulation improved pasta quality while reducing the leaching of its components into the cooking water. Pasta prepared with 1.00% xanthan gum showed the lowest cooking loss, the highest firmness, and the lowest adhesiveness. These results revealed a significant influence of xanthan gum content on pasta properties as confirmed by the thermal analysis and SEM microstructure observations.

Tiliroside is one of the main flavonoid compounds responsible for a wide spectrum of biological activity of Tilia L. Up to now, several extraction techniques have been reported for extracting this compound from Tilia L. In this work for the first time supercritical carbon dioxide extraction was used for this purpose. Experiments were performed using supercritical carbon dioxide with 5% and 10% of ethanol as solvent, aiming a recovery content of tiliroside, temperature from 45 to 80°C, pressure from 100 to 220 bar and time from 20 to 60 minutes. The statistically generated optimum extraction conditions to obtain the highest content of tiliroside were established as: pressure of 200 bar, temperature 65°C and 45-50 minutes for 5% ethanol concentration and pressure of 220 bar, temperature 65°C and 15 minutes for 10% ethanol concentration.

Chokeberry fruit (Aronia melanocarpa (Michx.) Elliott) is known for its antioxidant properties and generally beneficial impact on human health. The aim of the research was to produce innovative corn porridge with a different content of chokeberry fruit percentage-wise and to test it to determine the content of polyphenolic compounds, including flavonoids and individual free phenolic acids, and determine the antioxidant properties of analysed extracts. One of the objectives was also to identify the optimum porridge production parameters, including, among other things, the rotational speed of the extruder screw during the extrusion process.

Photocatalytic degradation is a promising method for removing persistent organic pollutants from water because of its low cost (see solar-driven photocatalysis), high mineralisation of pollutants, and low environmental impact. Photocatalysts based on transition metal dichalcogenides (TMDs) have recently attracting high scientific interest due to their unique electrical, mechanical, and optical properties. A MoS2 photocatalyst of the layered structure was managed to photodegrade methylene blue (MB) under visible light irradiation. The catalyst was thoroughly characterised using SEM, AFM, powder XRD, UV–Vis, Raman, and XPS measurements. The photocatalytic degradation of the MB solution was conducted under the following conditions: (i) reductive and (ii) oxidative. The impact of optical and electronic properties, and the MoS2-MB interaction on photocatalytic activity, was discussed. The apparent rate constants (kapp) of degradation were 3.7 × 10–3; 7.7 × 10–3; 81.7 × 10–3 min−1 for photolysis, oxidative photocatalysis, and reductive photocatalysis. Comparison of the degradation efficiency of MB in reductive and oxidative processes indicates the important role of the reaction with the surface electron. In the oxidation process, oxygen reacts with an electron to form a superoxide anion radical involved in further transformations of the dye, whereas, in the reduction process, the addition of an electron destabilises the chromophore ring and leads to its rupture. [ABSTRACT FROM AUTHOR]

Background: Advanced Oxidation Processes (AOPs) are the water treatment techniques that are commonly used forthe decomposition of the non-biodegradable organic pollutants. However, some pollutants are electron deficient and thus resistant to attack by reactive oxygen species (e.g., polyhalogenated compounds) but they may be degraded under reductive conditions. Therefore, reductive methods are alternative or supplementary methods to the well-known oxidative degradation ones. Methods: In this paper, the degradation of 4,4′-isopropylidenebis(2,6-dibromophenol) (TBBPA, tetrabromobisphenol A) using two Fe3O4 magnetic photocatalyst (F1 and F2) is presented. The morphological, structural and surface properties of catalysts were studied. Their catalytic efficiency was evaluated based on reactions under reductive and oxidative conditions. Quantum chemical calculations were used to analyse early steps of degradation mechanism. Results: The studied photocatalytic degradation reactions undergo pseudo-first order kinetics. The photocatalytic reduction process follows the Eley-Rideal mechanism rather than the commonly used Langmuir-Hinshelwood mechanism. Conclusions: The study confirms that both magnetic photocatalyst are effective and assure reductive degradation of TBBPA. [ABSTRACT FROM AUTHOR]