Seasonal Changes in Essential Oil Constituents of Cystoseira compressa: First Report

Marine macroalgae are well known to release a wide spectrum of volatile organic components, the release of which is affected by environmental factors. This paper aimed to identify the essential oil (EO) compounds of the brown algae Cystoseira compressa collected in the Adriatic Sea monthly, from May until August. EOs were isolated by hydrodistillation using a Clavenger-type apparatus and analyzed by gas chromatography coupled with mass spectrometry (GC–MS). One hundred four compounds were identified in the volatile fraction of C. compressa, accounting for 84.37–89.43% of the total oil. Samples from May, June, and July were characterized by a high share of fatty acids (56, 69, and 34% respectively) with palmitic acid being the dominant one, while in the August sample, a high content of alcohols (mainly phytol and oleyl alcohol) was found. Changes in the other minor components, which could be important for the overall aroma and biological activities of the algal samples, have also been noted during the vegetation periods. The results of this paper contribute to studies of algal EOs and present the first report on C. compressa EOs.     

Labdane Diterpenoids from Salvia tingitana Etl. Synergize with Clindamycin against Methicillin-Resistant Staphylococcus aureus

Quorum-sensing (QS) is a regulatory mechanism in bacterial communication, important for pathogenesis control. The search for small molecules active as quorum-sensing inhibitors (QSI) that can synergize with antibiotics is considered a good strategy to counteract the problem of antibiotic resistance. Here the antimicrobial labdane diterpenoids sclareol (1) and manool (2) extracted from Salvia tingitana were considered as potential QSI against methicillin-resistant Staphylococcus aureus. Only sclareol showed synergistic activity with clindamycin. The quantification of these compounds by LC–MS analysis in the organs and in the calli of S. tingitana showed that sclareol is most abundant in the flower spikes and is produced by calli, while manool is the major labdane of the roots, and is abundant also in the leaves. Other metabolites of the roots were abietane diterpenoids, common in Salvia species, and pentacyclic triterpenoids, bearing a γ-lactone moiety, previously undescribed in Salvia. Docking simulations suggested that 1 and 2 bind to key residues, involved in direct interactions with DNA. They may prevent accessory gene regulator A (AgrA) binding to DNA or AgrA activation upon phosphorylation, to suppress virulence factor expression. The antimicrobial activity of these two compounds probably achieves preventing upregulation of the accessory gene regulator (agr)-regulated genes.     

A Practical Approach for the In Vitro Safety and Efficacy Assessment of an Anti-Ageing Cosmetic Cream Enriched with Functional Compounds

(1) Background: Cosmeceuticals are topical products applied to human skin to prevent skin ageing and maintain a healthy skin appearance. Their effectiveness is closely linked to the compounds present in a final formulation. In this article, we propose a panel of in vitro tests to support the efficacy assessment of an anti-ageing cream enriched with functional compounds. (2) Methods: biocompatibility and the irritant effect were evaluated on reconstructed human epidermis (RHE) and corneal epithelium (HCE) 3D models. After a preliminary MTT assay, normal human dermal fibroblasts (NHDF) and keratinocytes (HaCaT) were used to evaluate the extracellular matrix (ECM) protein synthesis, and interleukin-6 (IL-6) and metalloproteinase-1 (MMP-1) production. (3) Results: data collected showed good biocompatibility and demonstrated the absence of the irritant effect in both 3D models. Therefore, we demonstrated a statistical increase in collagen and elastin productions in NHDF cells. In HaCaT cells, we highlighted an anti-inflammatory effect through a reduction in IL-6 levels in inflammatory stimulated conditions. Moreover, the reduction of MMP-1 production after UV-B radiation was demonstrated, showing significant photo-protection. (4) Conclusion: a multiple in vitro assays approach is proposed for the valid and practical assessment of the anti-ageing protection, anti-inflammatory and biocompatible claims that can be assigned to a cosmetic product containing functional compounds.     

Ionization of Ozone/Chlorofluorocarbon Mixtures in Atmospheric Gases: Formation and Dissociation of [CHX2O3]+ Complexes (X=Cl,F)

Complexes that undergo extensive molecular reorganization upon unimolecular metastable dissociation are obtained after ionization of atmospheric gases containing ozone and chlorofluorocarbons [Eq. (1)]. These unusual processes, which require fission of all bonds initially present in the CHX₂ unit (X=Cl, F) and combination of C with one of the O atoms of ozone, were demonstrated and their mechanism rationalized by the joint application of mass spectrometric and theoretical methods.     

Base-Assisted Conversion of Protonated D-Fructose to 5-HMF: Searching for Gas-Phase Green Models

A gas-phase investigation of the D -fructose dehydration reaction in the presence of base has been performed by the joint application of mass spectrometric techniques and theoretical calculations. Protonated addition products of D -fructose and base were generated in the gas phase by electrospray ionization using several bases of different proton affinity. The intermediates, products and decomposition channels were investigated by ion trap mass spectrometry. Electronic structure calculations allowed the identification of the ionic intermediates and products of a selected system containing NH₃, helping to rationalize the observed reaction pathways. The obtained results show that the final product, the protonated 5-hydroxymethyl-2-furaldheyde [5-HMF]H⁺, is better formed using selected bases and only if these remain clustered until the end of the dehydration process.     

Signal processing to evaluate parameters affecting SPE for multi‐residue analysis of personal care products

This paper discusses the development of a comprehensive method for the simultaneous analysis of personal care products (PCPs) based on SPE and GC‐MS. The method was developed on 29 target compounds to represent PCPs belonging to different chemical classes: surfactants in detergents (alkyl benzenes), fragrances in cosmetics (nitro and polycyclic musks), antioxidants and preservatives (phenols), plasticizers (phthalates) displaying a wide range of volatility, polarity, water solubility. In addition to the conventional C₁₈ stationary phase, a surface modified styrene divinylbenzene polymeric phase (Strata^TM X SPE cartridge) has been investigated as suitable for the simultaneous extraction of several PCPs with polar and non‐polar characteristics. For both sorbents different solvent compositions and eluting conditions were tested and compared in order to achieve high extraction efficiency for as many sample components as possible. Comparison of the behavior of the two cartridges reveals that, overall, Strata‐X provides better efficiency with extraction recovery higher than 70% for most of the PCPs investigated. The best results were obtained under the following operative conditions: an evaporation temperature of 40°C, elution on Strata‐X cartridge using a volume of 15 mL of ethyl acetate (EA) as solvent and operating with slow flow rate (–10 KPa). In addition to the conventional method based on peak integration, a chemometric approach based on the computation of the experimental autocovariance function (EACVF_tot) was applied to the complex GC‐MS signal: the percentage recovery and information on peak abundance distribution can be evaluated for each procedure step. The PC‐based signal processing proved very helpful in assisting the development of the analytical procedure, since it saves labor and time and increases result reliability in handling GC complex signals.     

Effects of Combination Treatments with Astaxanthin-Loaded Microparticles and Pentoxifylline on Intracellular ROS and Radiosensitivity of J774A.1 Macrophages

Radiation-induced fibrosis (RIF) is a serious, yet incurable, complication of external beam radiation therapy for the treatment of cancer. Macrophages are key cellular actors in RIF because of their ability to produce reactive oxidants, such as reactive oxygen species (ROS) and inflammatory cytokines that, in turn, are the drivers of pro-fibrotic pathways. In a previous work, we showed that phagocytosis could be exploited to deliver the potent natural antioxidant astaxanthin specifically to macrophages. For this purpose, astaxanthin encapsulated into µm-sized protein particles could specifically target macrophages that can uptake the particles by phagocytosis. In these cells, astaxanthin microparticles significantly reduced intracellular ROS levels and the secretion of bioactive TGFβ and increased cell survival after radiation treatments. Here we show that pentoxifylline, a drug currently used for the treatment of muscle pain resulting from peripheral artery disease, amplifies the effects of astaxanthin microparticles on J774A.1 macrophages. Combination treatments with pentoxifylline and encapsulated astaxanthin might reduce the risk of RIF in cancer patients.     

Chemistry of cobalt(II) confined in the pores of ordered silica monoliths: from the formation of the monolith to the CoFe Prussian blue analogue nanocomposite

Recently we conceived of an original strategy that allows the precipitation of Prussian blue analogues (PBAs) in the ordered pores of silica monoliths to lead to photomagnetic CoFe PBA-silica nanocomposites. To determine the critical parameters and fully control the synthesis of the photoactive CoFe PBA in the pores of the silica matrix, X-ray absorption spectroscopy was performed at the cobalt K-edge. This study showed that cobalt cation chemistry is the keystone of the entire process. The local environment and the electronic structure of the cobalt cation undergo several modifications during the formation process: first the incorporation of the cation as an octahedral complex into the ordered block copolymer phase, then the deprotonation by thermohydrolysis to give a fourfold-coordinated deprotonated lowly condensed species and finally the formation of the 3D coordination network of CoFe PBA in acidic conditions through a rapid reprotonation followed by nucleophilic substitution accompanied by the electronic transfer, thus leading to the photomagnetic Co(III)(LS)-Fe(II)(LS) (LS=low spin) pairs.