Anthocyanins as Key Phytochemicals Acting for the Prevention of Metabolic Diseases: An Overview

Anthocyanins are water-soluble pigments present in fruits and vegetables, which render them an extensive range of colors. They have a wide distribution in the human diet, are innocuous, and, based on numerous studies, have supposed preventive and therapeutical benefits against chronic affections such as inflammatory, neurological, cardiovascular, digestive disorders, diabetes, and cancer, mostly due to their antioxidant action. Despite their great potential as pharmaceutical applications, they have a rather limited use because of their rather low stability to environmental variations. Their absorption was noticed to occur best in the stomach and small intestine, but the pH fluctuation of the digestive system impacts their rapid degradation. Urine excretion and tissue distribution also occur at low rates. The aim of this review is to highlight the chemical characteristics of anthocyanins and emphasize their weaknesses regarding bioavailability. It also targets to deliver an update on the recent advances in the involvement of anthocyanins in different pathologies with a focus on in vivo, in vitro, animal, and human clinical trials.     

The Distribution of Thorium in Fluorite Single Crystals

Single crystals of CaF₂ doped with ThO₂ were grown by the Czochralski-Kyropoulos technique in graphite crucibles. The distribution of thorium in the as grown crystals has been investigated by optical and transmission electron microscopy, selected area diffraction and optical spectroscopy.     

Investigation of the complexation of essential oil components with cyclodextrins

The formation of inclusion complexes of six essential oil (EO) components (β-caryophyllene, cis-ocimene, trans-ocimene, sabinene hydrate (thujanol), γ-terpinene and α-terpineol) with six cyclodextrins (CDs) (α-CD, β-CD, γ-CD, HP-β-CD, RAMEB and CRYSMEB) was investigated by using static headspace-gas chromatography and UV–visible spectroscopy. Retention studies showed that CDs could efficiently reduce the volatility of EO components except for β-caryophyllene with α-CD. In this case, no inclusion complex was detected while for other compounds the formation of 1:1 inclusion complexes was observed. Results revealed that the inclusion stability mainly depends on geometric complementarity between encapsulated molecule and CD's cavity. Molecular modelling was used to investigate the complementarities between host and guest. Thus, CDs could efficiently be regarded as promising encapsulants for EO components leading to improve their application in cosmetic, pharmaceutical and agriculture fields.     

Polyol-modified layered double hydroxides with attenuated basicity for a truly reversible capture of CO2

Dendrimers bearing hydroxyl groups supported by layered double hydroxides (CO₃–LDH) with Mg/Al ratio ranging from 1:1 to 5:1 showed improved properties for the reversible capture of carbon dioxide (CO₂). The adsorption capacity of the starting LDH was due to the intrinsic base-like behavior, and was found to depend on the Mg/Al ratio. When contacted with polyol dendrimers in aqueous media, no intercalation took place. This was explained in terms of low exfoliation grade of LDH and hydrophobic character of the dendrimer molecules. The latter rather adsorb on the external surface of the LDH stacks for low dendrimer loadings, or aggregate into organic clusters for higher contents. Analyses through thermal programmed desorption of CO₂ revealed that dendrimer incorporation advantageously attenuates the basicity strength of the starting LDH support, by lowering the desorption temperature. The OH groups of the organic moiety were found to display an amphoteric character, and act as the main adsorption sites. The weak interactions with CO₂ facilitate easier release of the major part of adsorbed CO₂ at temperature not exceeding 80–100 °C. On polyol organo-LDHs, the reversible CO₂ retention was discussed herein in terms of acid–base interactions. This concept allows envisaging the capture of diverse pollutants and other greenhouse gases by modifying the chemical groups on the dendritic moiety.     

Attempts for Developing Novel Sugar-Based and Sugar-Free Sea Buckthorn Marmalades

Sea buckthorn (Hippophaė rhamnoides L.) is recognized as a valuable source of vitamin C and antioxidants, frequently used as nutraceuticals and cosmeceuticals. In the present study, attempts are made to produce and characterize a novel type of marmalade using sea buckthorn berries processed at 102 °C into marmalade in two combinations, with whole cane or stevia sugar. Changes in the phytochemical profile, antioxidant activity, color, shelf-life, texture, microbiological, and sensorial characteristics were determined. The total carotenoids content in the marmalades were significantly different, with values of 0.91 ± 0.03 mg/g dry weight (DW) in the sample with whole sugar cane (C_z) and 2.69 ± 0.14 mg/g DW in the sample with Stevia sugar (C_s). Significant values of polyphenols were found, of 59.41 ± 1.13 mg GAE/g DW in C_z and 72.44 ± 2.31 mg GAE/g DW in C_s, leading to an antioxidant activity of 45.12 ± 0.001 μMol Trolox/g DW and 118.07 ± 0.01 μMol Trolox/g DW, respectively. Accelerated storage study showed a decrease in all the phytochemicals, however no significant changes were found in antioxidant activity. Values of <100 CFU/g for yeasts and molds and <5 CFU/g for Enterobacteriaceae after 21 days of storage at the room temperature of the marmalades were determined. The sensorial and color results were more than acceptable. Overall, the results highlighted the potential of using sea buckthorn as a potential rich source of bioactive compounds to be used in the sugar-based products manufacturing.     

Wastes from Wood Extraction Used in Composite Materials: Behavior after Accelerated Weathering

New materials were obtained by incorporating in polypropylene (PP) matrix 60% wood wastes resulting after extraction with supercritical carbon dioxide, water, and ethanol. Structural, mechanical, thermal, and rheological characterizations, as well as moisture uptake of the composites, were evaluated before and after accelerated weathering. It was found that the extraction method influenced the composite properties due to the hydrophilic-hydrophobic balance. The addition of extracted fibers results in an increase in hardness and tensile properties and a decrease of impact strength as compared to PP.     

Moisture resistance of polished and coated KCl windows

The moisture resistance of ultratransparent KCl grown in a reactive atmosphere was studied on polished KCl samples coated with protective films of BaF₂. The lifetime was improved about 4 times compared with uncoated samples. A further improvement was obtained by additional chemical polishing before coating. However, in such a case buckling of the film in a pattern of narrow parallel stripes was observed in an intermediate stage of the humidity test.     

p-type ZnO thin films grown by RF plasma beam assisted Pulsed Laser Deposition

The high exciton binding energy and band gap energy of ZnO thin films open the prospect of fabricating semiconductor lasers in the ultraviolet spectral range. A prerequisite for laser diode fabrication is highly p-doped ZnO which was not reproducibly obtained up to now. Without intentional doping ZnO exhibits n-type conduction. ZnO thin films have been obtained by radio-frequency assisted pulsed laser deposition. A metallic Zn target was used for ablation in an oxygen and nitrogen RF discharge. The electrical and morphological properties of the films grown on Si were studied by Atomic Force Microscopy (AFM), X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), optical absorption and Hall Effect measurements for different ratios between the nitrogen and oxygen content. The AFM images of the as-grown ZnO films reveal high quality surfaces with low values for the surface roughness and a sharp distribution of grains sizes as an effect of the RF discharge. The XRD patterns for all samples exhibit only (002) and (004) peaks indicating that the c-axis is always oriented normal to the substrate surface. The films present p-type conductivity with different carrier concentration and mobility depending on the nitrogen/oxygen ratio.     

Copolymerization of 2‐hydroxyethyl methacrylate with a comonomer with spiroacetal moiety

The study reports the synthesis of a copolymer based on 2‐hydroxyethyl methacrylate and 3,9‐divinyl‐2,4,8,10‐tetraoxaspiro[5.5]undecane (U) acquired through radical polymerization in the presence of 2,2′‐azobis(2‐methylpropionitrile). The attempt was to have a solid content as high as 10 wt %. The polymerization process was conducted in the presence of a classic ionic surfactant—sodium lauryl sulfate—and comparatively using two variants of protective colloid β‐cyclodextrin and poly(aspartic acid), respectively. The prepared dispersions were characterized from the viewpoint of their hydrodynamic radius, zeta potential, and conductivity evolution during syntheses. The mean particle size and size distribution and zeta potential and conductivity were also evaluated for the synthesized polymeric particles. The compositions of the polymers were confirmed by FTIR and ¹H NMR spectra, and also, the thermal stability of the polymeric compounds was evaluated. SEM and AFM investigations of the polymer morphology are also presented. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011