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The imbalance in skin microbiota is characterized by an increased number of pathogens in respect to commensal microorganisms. Starting from a skin microbiota collection, the aim of this work was to evaluate the possible role of Pomegranate (Punica granatum L.) Peel Extract (PPE) in restoring the skin microbiota balance acting on Staphylococcus spp. PPE was extracted following green methodology by using n-butane and the Dimethyl Ether (DME) solvents and analyzed for phytochemical composition and antimicrobial activity. The PPE antimicrobial action was evaluated against Gram +, Gram − bacteria and yeast reference strains and the most effective extract was tested against the main skin microbiota isolated strains. PPE extracted with DME showed the best antimicrobial action with MICs ranging from 1 to 128 mg/mL; the main active compounds were Catechin, Quercetin, Vanillic acid and Gallic acid. The PPE in DME anti-adhesive effect was examined against S. epidermidis and S. aureus mono and dual-species biofilm formation by biomass quantification and CFU/mL determination. The extract toxicity was evaluated by using Galleria mellonella larvae in vivo model. The extract displayed a significant anti-adhesive activity with a remarkable species-specific action at 4 and 8 mg/mL against S. epidermidis and S. aureus mono and dual-species biofilms. PPE in DME could represent an eco-sustainable non-toxic strategy to affect the Staphylococcal skin colonization in a species-specific way. The innovation of this work is represented by the reuse of food waste to balance skin microbiota. [ABSTRACT FROM AUTHOR]

Recent studies indicate that mass concentration alone is not the best parameter to assess the toxicity and the health effects of particulate matter (PM). Indeed, the chemical composition of the particles plays an important role, and oxidative potential (OP) measurements are being proposed as an alternative way to assess toxicity. The European Union (EU) is currently proposing a draft of the new air quality directive which includes OP measurements but does not specify the methods and/or protocols of analysis. In this light, the purpose of this study was to evaluate the feasibility of two literature assays, namely ascorbic acid (AA) and dithiothreitol (DTT), for routine PM analysis by testing urban PM filters from a one-year sampling campaign conducted by ARPA Lombardia. Indoor PM samples were also tested to emphasize the importance of monitoring closed spaces in which people spend most of their time. Following the optimization of the DTT assay, both methods proved to be suitable for large-scale PM analysis. The results show that the oxidative strength of urban PM is constant throughout the year for the outdoor samples (OPAA: 0.067–0.39 nmol min−1 m−3; OPDTT: 0.033–0.109 nmol min−1 m−3), indicating the need for routine OP monitoring. Instead, indoor areas were characterized by particles with a lower oxidative capacity (OPAA: 5.40–24 pmol min−1 m−3; OPDTT: 9.7–32 pmol min−1 m−3), driven both by lower concentrations and a different chemical composition. All the data collected highlight the need to add this parameter as part of the chemical characterization of PM, moving in the same direction as the new EU air quality directive. [ABSTRACT FROM AUTHOR]

The present study deals with the determination of pollutant emissions from wood-fired pizza ovens throughout the implementation of an innovative sampling system, specifically designed for the source in question. The experiments were conducted on a traditional wood-fired oven using two different forms of beechwood as fuel: wood logs and briquettes. Three different combustion cycles were used to carry out the tests, two for the wood logs and one for the briquettes. Different sampling sites along the system allowed for the collection and analysis of several gaseous pollutants, such as nitrogen oxides (NOx), carbon monoxide (CO), carbon dioxide (CO2) and OGC (organic gaseous carbon); along with total particulate matter (TPM). In order to study the synergistic effect of biomass burning and pizza cooking, combustion cycles were performed both with and without the presence of the pizzas. The results show that the concentrations of gaseous pollutants were affected mainly by the combustion conditions in the oven, whereas the values of TPM depended more on the amount of fuelwood used. Pizza cooking had a great impact on the emissions of OGC and, to a lesser extent, on CO and TPM. [ABSTRACT FROM AUTHOR]

Empirical potentials and Born-von Karman harmonic lattice dynamic calculations of varying degrees of sophistication were applied in a study to interpret Raman and vibrational spectra of minerals. In this particular study, the spectra of the phenakite Be2SiO4 was examined using an oriented single crystal and a rigid-ion (or rigid-atom) model. Results suggest that even for ionic inorganic compounds, such as most minerals, the force fields are essentially transferable.

Featured Application: The deposition rate is a relevant and novel issue in air quality evaluation. Particularly, atmospheric micropollutant deposition rate measures represent a strategic element in environmental surveillance and in population exposure evaluation for POPs and metals. In recent years, studies on climate change have focused on reducing greenhouse gas emissions emitted by various civil and industrial processes. This study highlights the importance of characterizing the total deposition rates of airborne particles (bulk atmospheric deposition) in the surroundings of an industrial area along the north cost of the Lazio Region in Italy, to deepen knowledge about the potential impact of emissions from the coal-fired thermoelectric (CTE) power plant and other possible sources existing in the surrounding area. Four sampling sites were identified, and the monitoring plan was performed a yearlong with monthly collecting observation. The deposition samples were collected monthly and processed for determining organic (polychlorinated dibenzo-para-dioxins, PCDDs; polychlorinated dibenzofurans, PCDFs; dioxin-like polychlorinated biphenyls, DL-PCBs; polycyclic aromatic hydrocarbons, PAHs) and inorganic (metals) substances. The samples were collected monthly and sent for chemical characterization. In Europe and Italy, no reference values have been given for the deposition rates of chemicals, while some European countries have determined reference/guide values to which the authors will refer in this study. Therefore, the analytical results show that the deposition rates for PCDD/Fs and DL-PCBs are lower with respects guide values defined by Germany and Belgium; PAHs values are in line with those measured in other rural-type sites, while for metals the analytical results show a situation between rural and urban area. The approach used in this study can help to identify reference values for Italy in deposition rates, with the aim both to characterize the dynamic of pollution in area with multiple risk factors and to describe and protect human health from environmental exposures caused by the contamination of the food chain. [ABSTRACT FROM AUTHOR]

This research deals with the characterization of black crusts collected from the Dome of Monza (Milan, Italy). Air pollution is responsible for the degradation of historical buildings surfaces. In urban and industrial areas, the degradation process is accelerated, due to carbonaceous particles and heavy metals emitted by combustion processes which contribute to the formation of black crust (BCs). In this study the characterization of BC was performed using different analytical techniques such as: HRSEM-EDX, IC, LA-ICP/MS and digital image analysis. In particular, the research focused on the study of "heavy metals" which contribute to the identify the main sources of pollution responsible for the surface's deterioration over time. BCs variability in composition also depends on the exposure of the analyzed surfaces. [ABSTRACT FROM AUTHOR]