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A study aimed to monitor the composting process and to evaluate the effectiveness of indicators able to define the stability of a compost obtained by mixing municipal solid waste (MSW) and vegetal waste, was conducted. For this reason, composting process lasting 3 months, was monitored by chemical and thermal analysis. Total organic carbon (TOC), total extractable carbon (TEC) and humic and fulvic acid carbon (HA and FA, respectively) were determined after extraction, fractionation and analysis of organic matter from samples collected during the composting process. Differential scanning calorimetry (DSC), thermogravimetry (TG) and the first derivative of the TG (DTG) were simultaneously performed in oxidizing conditions on grounded compost samples and HA extracted. Thermoanalitical data resulted to be useful in integrating quantitative information coming from chemical analysis of humified fraction of compost organic matter. Particularly DSC curves allowed to distinguish between well and poor stabilized organic matter, and information deriving from weight losses, registered by the TG and DTG curves, enable to individuate the evolution state of the organic matter and therefore its stability.

Sediment characteristics and Cd, Cu, Mn, Pb and Zn concentrations were assessed in the lagoons of Marceddì, Calich and Porto Pozzo, and in the inner part of the Gulf of Olbia. Sediment of the zones examined were quite similar, except for the Calich lagoon that showed the higher content of total organic carbon. High values of Cd, Pb and Zn were detected in the sediments of the Marceddì lagoon, while remarkable levels of Cu and Mn were found in the Calich lagoon and in the Gulf of Olbia.

Journal of medicinal chemistry 63(13), 6694 - 6707 (2020). doi:10.1021/acs.jmedchem.9b01942, Stabilization of protein–protein interactions (PPIs) holds great potential for therapeutic agents, as illustrated by the successful drugs rapamycin and lenalidomide. However, how such interface-binding molecules can be created in a rational, bottom-up manner is a largely unanswered question. We report here how a fragment-based approach can be used to identify chemical starting points for the development of small-molecule stabilizers that differentiate between two different PPI interfaces of the adapter protein 14-3-3. The fragments discriminately bind to the interface of 14-3-3 with the recognition motif of either the tumor suppressor protein p53 or the oncogenic transcription factor TAZ. This X-ray crystallography driven study shows that the rim of the interface of individual 14-3-3 complexes can be targeted in a differential manner with fragments that represent promising starting points for the development of specific 14-3-3 PPI stabilizers., Published by ACS, Washington, DC

The effect of long-term ageing (up to 700 days) on the mobility, potential bioavailability and bioaccessibility of antimony (Sb) was investigated in two soils (S1: pH 8.2; S2: pH 4.9) spiked with two Sb concentrations (100 and 1000 mg·kg−1). The Sb mobility decreased with ageing as highlighted by sequential extraction, while its residual fraction significantly increased. The concentration of Sb (CDGT), as determined by diffusive gradients in thin films (DGT), showed a reduction in potential contaminant bioavailability during ageing. The DGT analysis also showed that Sb-CDGT after 700 days ageing was significantly higher in S1–1000 compared to S2–1000, suggesting soil pH plays a key role in Sb potential bioavailability. In-vitro tests also revealed that Sb bioaccessibility (and Hazard Quotient) decreased over time. Linear combination fitting of Sb K-edge XANES derivative spectra showed, as a general trend, an increase in Sb(V) sorption to inorganic oxides with ageing as well as Sb(V) bound to organic matter (e.g. up to 27 and 37% respectively for S2–100). The results indicated that ageing can alleviate Sb ecotoxicity in soil and that the effectiveness of such processes can be increased at acidic pH. However, substantial risks due to Sb mobility, potential bioavailability and bioaccessibility remained in contaminated soils even after 700 days ageing. Refereed/Peer-reviewed

The studies on the influence of organic-based sorbents on the mobility of potentially toxic elements (PTE) in contaminated soils have been constantly growing in the last decades. However, given the variety of PTE and pollution status, as well as the diversity of factors governing the fate of PTE in soil, to date it is still hard to foresee the amendment effectiveness in a specific soil environment. The aim of this PhD thesis was therefore to assess the influence of biochar, compost and their combination on the mobility, (phyto)toxicity and bioavailability of several PTE (i.e. Sb, As, Ni, Cr and Zn) present in different polluted soils of Lebanon. The addition of compost, biochar and their combination generally reduced labile PTE pools (i.e. readily soluble) and increased their residual (non-extractable) fractions. The amendments also changed the C-source utilization potential of the soil microbial community as revealed by the Biolog community level physiological profile. At the same time, soil dehydrogenase, β-glucosidase and urease were significantly enhanced in amended soils while the growth of Capsicum annuum L. and Triticum aestivum L. (in a selected polluted soil) was significantly enhanced and PTE uptake significantly reduced. Overall, the results obtained indicated that biochar and compost could be useful to stabilise PTE in contaminated soils, to stimulate soil microbial activity and functionality and to improve plant growth.

Antimony (Sb) and its compounds are emerging priority pollutants which pose a serious threat to the environment. The aim of this study was to evaluate the short-term fate of antimonate added to different soils (S1 and S2) with respect to its mobility and impact on soil microbial communities and soil biochemical functioning. To this end, S1 (sandy clay loam, pH 8.2) and S2 (loamy coarse sand, pH 4.9) soils were spiked with 100 and 1000 mg Sb(V) kg−1 soil and left in contact for three months. Sequential extractions carried out after this contact time indicated a higher percentage of labile antimony in the Sb-spiked S1 soils than S2 (e.g. ~13 and 4% in S1 and S2 treated with 1000 mg Sb(V) kg−1 respectively), while the opposite was found for residual (hardly bioavailable) Sb. Also, a reduced number of culturable heterotrophic bacteria was recorded in Sb-spiked S1 soil (compared to the unpolluted S1), while an increased one was found in S2. Heterotrophic fungi followed the opposite trend. Actinomycetes and heat-resistant aerobic bacterial spores showed a variable trend depending on the soil type and Sb(V) treatment. The Biolog community level physiological profile indicated a reduced metabolic activity potential of microbial communities from the Sb-spiked S1 soils (e.g. 2-fold for Sb-1000). The soil dehydrogenase activity followed the same trend. High-throughput 16S rRNA amplicon sequencing analysis revealed that Sb did not influence the bacterial α-diversity in both soils, while significantly affected the composition of the respective soil bacterial communities. Several phyla (e.g. Nitrosospira Nitrososphaeraceae, Adheribacter) were found positively correlated with the concentration of water-soluble Sb in soil. Overall, the results obtained suggest that the risk assessment in soils polluted with antimony should be a priority especially for alkaline soils where the high mobility of the anionic Sb(OH)6ˉ species can pose, at least in the short-term, a serious threat for soil microbial abundance, diversity and functionality, soil fertility and eventually human health. Refereed/Peer-reviewed

Iron-rich water treatment residues (Fe-WTRs) and municipal solid waste compost (MSWC) were added together at two different total rates (i.e. 0.5% Fe-WTRs+0.5% MSWC and 1% Fe-WTRs+1% MSWC) to a degraded sub-alkaline soil (pH 8.0) contaminated with Sb (∼110 mg kg−1 soil), Pb (∼1200 mg kg−1), Cd (∼23 mg kg−1), and Zn (∼5400 mg kg−1). A large number of chemical and biological endpoints were evaluated to assess the efficacy of the treatments after five months of incubation. Both treatments significantly reduced the labile fractions of the metal(loid)s in soil, especially Sb, while increasing the abundance of culturable heterotrophic bacteria, actinomycetes and fungi (i.e. up to 6.3-, 1.6- and 4.1-fold higher than control respectively). Soil enzyme activities, i.e. dehydrogenase, β-glucosidase and urease, were also significantly enhanced in the treated soils (i.e. up to ∼12-, 3- and 2-fold higher than control respectively). The amendment addition affected the structure of the soil microbial community as highlighted by the higher metabolic potential and catabolic versatility of treated soils (Biolog CLPP) and by the significantly higher α-diversity values based on high throughput partial 16S rRNA gene sequencing. Moreover, analysis of the dominant operational taxonomic units (OTUs) showed differences in the microbial communities of untreated and treated soils. Plant growth (Helichrysum italicum) in the treated soils was greatly stimulated while metal(loid)s uptake was significantly reduced. Overall, the results indicated that the applied treatment could be ideal for the chemical and (micro)biological recovery of sub-alkaline soils contaminated with Sb and co-occurring metals, and H. italicum appears to be a promising plant species for aided phytostabilisation of such soils. Refereed/Peer-reviewed

article i nfo Two industrial by products, red mud (RM) and aluminum-rich water treatment residue (Al-WTR) were used (2% w/w) for the immobilization of As, Cu and Pb in two polluted soils. Soil-1 was a mine contaminated soil (2428 As, 234 Cu and 559 Pb mg kg −1 ); Soil-2 was a chromated copper arsenate contaminated soil (860 and 1500 mg kg −1 of As and Cu respectively). Two different redox conditions (aerobic and 3 repeated reduction/oxidation cycles) were also applied. The immobilization of trace elements and their bioaccessibility were evaluated through a leaching test and simplified bioaccessibility extraction test (SBRC) respectively, whereas phytoavailability was assessed in pot trials with Lolium perenne. The RM addition increased the solubility of As and Pb, under both redox conditions, in Soil-1 with respect to untreated soil (i.e., +40 and 38% respectively in RMsw-Soil-1 in aerobic condition). In Soil-2 Al-WTR was the amendment most efficient at decreasing As mobility (b50% with respect to untreated soil). The high correlations detectedbetweentraceelementmobilityanddissolvedorganiccarbon(DOC)suggeststhatAs,CuandPbformed soluble organic complexes. The SBRC results suggested that this test was mainly affected by physical and chemicalcharacteristics of soils, whereastrial pot showed that thetreatments with RMsw and Al-WTR inaerobic condition wereableto decrease theplant uptake of Asby 34 and 57% inSoil-1,and by 88 and 87% inSoil-2. These treatments also reduced uptake of Cu from Soil-2 (by 68 and 86%) and of Pb from Soil-1 (by 52 and 34%). The results of this study show that the efficacy of the soil amendments is a complex function of soil conditions, source of contamination, and perhaps most importantly the environmental endpoint considered.

In this study we determined, at different pH values (pH 4, 7 and 9), the ability of a Fe- and an Al-based water treatment residues (WTRs) to accumulate As(V) from an aqueous solution and to define the mechanisms which regulate the sorption of this anion. The Fe-WTR showed a greater As(V) sorption capacity with respect to Al-WTR at all the pH values studied [e.g. 1.65 mmol•g-1 and 1.02 mmol•g-1 of As(V) sorbed at pH 4 respectively]. Sequential extraction of As(V)-WTR suggests that the main mechanism governing the sorption of As(V) likely involved the formation of inner-sphere surface complexes [Fe/Al–O–As]. The capacity of Fe- and Al-WTR to decrease the mobility and bioaccessibility of As in a polluted sub-acidic soil (~2267 mg•kg-1 d.m.) was also evaluated. The addition of both sorbents at two application rates (1 and 2% w/w) induced a shift of the labile As fractions towards different ones more strongly retained by the components of WTRs (particularly by the Fe/Al amorphous (hydr)oxides), with the consequent decrease of the As mobility. All the treatments favoured a decrease (even if not significantly) of As bioaccessibility, evaluated through the SBET (stomach phase extraction at pH 1.5) and the SBRCG (intestinal phase extraction at pH 7.0) analyses, which simulate the gastrointestinal processes. The results presented show that both WTRs can be useful at decreasing the mobility and bioaccessibility of As, so favouring a certain recovery of the functionality of polluted soil.