Publications

Abstract Given the growing scarcity of water and the continuous increase in emerging pollutants detected in water bodies, there is an imperative need to develop new, more effective, and sustainable treatments for wastewater. Advanced oxidation processes (AOPs) are considered a competitive technology for water treatment. Specifically, ozonation has received notable attention as a promising approach for degrading organic pollutants in wastewater. However, different groups of pollutants are hardly degradable via single ozonation. With continuous development, it has been shown that using engineered nanomaterials as nanocatalysts in catalytic ozonation can increase efficiency by turning this process into a low-selective AOP for pollutant degradation. Nanocatalysts promote ozone decomposition and form active free radicals responsible for increasing the degradation and mineralization of pollutants. This work reviews the performances of different nanomaterials as homogeneous and heterogeneous nanocatalysts in catalytic ozonation. This review focuses on applying metal- and carbon-based engineered nanomaterials as nanocatalysts in catalytic ozonation and on identifying the main future directions for using this type of AOP toward wastewater treatment.

Abstract The thermal behaviour of bathophenanthroline and bathocuproine has been studied using several techniques, namely, differential scanning calorimetry and thermogravimetry. To determine their respective enthalpies of sublimation, vapor pressure measurements were carried out using different methods, such as Knudsen effusion mass loss/mass spectrometry, isothermal thermogravimetry, and a quartz crystal microbalance technique. Furthermore, the enthalpies of sublimation were determined by measuring the heat change of the sublimation process using high-temperature Calvet microcalorimetry. The results obtained in this work allowed the determination of the standard molar enthalpies of sublimation at 298.15 K, for bathophenanthroline and bathocuproine. The values obtained were (183.8 +/- 2.2) kJ & sdot;mol- 1 and (206.2 +/- 2.8) kJ & sdot;mol- 1, respectively. Additionally, the standard molar enthalpies of fusion were determined to be (30.4 +/- 0.4) kJ & sdot;mol- 1 and (26.5 +/- 1.6) kJ & sdot;mol- 1 for bathophenanthroline and bathocuproine, respectively. The analysis of the results allows a deeper understanding of the phase transition behavior for these compounds from the condensed to the gaseous phases, elucidating molecular decomposition and the inherent intermolecular forces governing the species.

Abstract Urban agricultural soils have important social, environmental, and economic roles in big cities, contributing to their sustainability. However, food production in urban soils may be compromised due to soil pollution that resulted from decades of industrial, non-regulated environmental activity and mobile transport. In this study, 12 soils from the urban agricultural area of Rome (Italy) were analyzed for the potentially toxic elements (PTEs) Be, Ba, Pb, Co, Ni, V, Zn, Hg, Cd, As, Cu, and Cr. All but one of the soils under analysis were characterized by at least one PTE concentration above the threshold limit defined by the D.Lgs 152/06 for agricultural soils. Multivariate analysis showed that the soils could be classified into five clusters: clusters I and II had relatively lower mean PTE concentrations; clusters III, IV, and V had relatively higher mean PTE concentrations with several PTE concentrations above the threshold proposed by ILD. Three factors contributing to the variability of the PTE's concentration in the soils under investigation were identified: a geological factor related to PTE As, Ba, Be, and V; an anthropogenic factor related to Pb and Cu; and a mixed factor related to Co, Cr, Ni, and Zn. High PTE content may limit the utilization of urban soils for food production.

Abstract <jats:p>Urban gardens have important social, environmental and economic roles in big cities, contributing to their sustainability. However, food production in urban gardens may be compromised due to soil pollution that resulted from decades of industrial non-regulated environmental activity and mobile transport. In this study, 12 soils from the urban agricultural area of Rome (Italy) were analyzed for the metals Be, Ba, Pb, Co, Ni, V, Zn, Hg, Cd, As, Cu, and Cr. All but one of the soils under analysis were characterized by at least one metal concentration above the threshold limit defined by the Italian Legislative Decree 152/2006 (ILD) for agricultural soils. Multivariate analysis showed that the soils could be classified into five clusters: clusters I and II had relatively lower mean metal concentrations; clusters III, IV, and V had relatively higher mean metal concentrations with several metal concentrations above the threshold proposed by ILD. Three factors contributing to the variability of the metal’s concentration in the soils under investigation were identified: geological factor, related with metals As, Ba, Be, and V; anthropogenic factor, related with Pb and Cu; and, a mixed factor related with Co, Cr, Ni, and Zn. High metal content may limit the utilization of urban soils as urban gardens for food production.</jats:p>

Abstract <jats:p>Mozambique is one of the poorest countries of the world. However, it has natural resources and if they are managed under sustainable development principles, Mozambique can overcome the current problems. In the present socio-economic status, soil is one of its most important resources and must be protected from pollution and from degradation. This review focuses on the identification and discussion of the main soil quality stressors, namely: soil fertility; deforestation and its sources: agriculture, timber harvesting, charcoal production and uncontrolled fires; mining activities, manly gold artisanal explorations and industrial open-pit coal mining. The sustainable use of the natural resources is mandatory to allow future generations to continue profiting for this nature-based wealth.</jats:p>

Abstract Agriculture is the main economic activity of Mozambique and there is a lack of information about the quality of agricultural soils. In this paper, five soils from the Manica and Sussundenga districts (Manica province) sampled in the years 2021/2022 and 2022/2023 (before and after the rainy seasons) were subjected to an agronomical and environmental chemical analysis to assess their quality, from the fertility and environmental contamination points of view. Standard analytical methodologies from external certified laboratories and local X-ray fluorescence measurements were used. All the studied soils were acidic (pH ranging from 4.5 to 5.4), had no salinity problems (conductivity ranging from 4.2 to 11.8 mS/m), and had a low amount of soil organic matter (0.90% to 1.81%). Soils from the Sussundenga district had a very low cation exchange capacity (CEC) (average of 3.33 cmol(c)/kg), while that of those from the Manica district ranged from very low to average CEC (3.59 to 13.11 cmol(c)/kg). Sussundenga soils also had a phosphorous deficiency (values ranging from <20 to 38.5 mg/kg) and there were deficiencies and/or excesses of some macro and micronutrients in all soil samples. Manica soils were contaminated, apparently from geogenic origin, with Cr (280 to 1400 mg/kg), Co (80 mg/kg), Ni (78 to 680 mg/kg) and V (86 mg/kg). Agricultural soil monitoring must be fostered in Mozambique in order to improve food quality and quantity to ensure economic and environmental sustainability.

Abstract Staphylococcus aureus is characterized by its high resistance to conventional antibiotics, particularly methicillinresistant (MRSA) strains, making it a predominant pathogen in acute and chronic wound infections. The persistence of acute S. aureus wound infections poses a threat by increasing the incidence of their chronicity. This study investigated the potential of photodynamic activation using phytochemical-antibiotic combinations to eliminate S. aureus under conditions representative of acute wound infections, aiming to mitigate the risk of chronicity. The strategy applied takes advantage of the promising antibacterial and photosensitising properties of phytochemicals, and their ability to act as antibiotic adjuvants. The antibacterial activity of selected phytochemicals (berberine, curcumin, farnesol, gallic acid, and quercetin; 6.25 - 1000 mu g/mL) and antibiotics (ciprofloxacin, tetracycline, fusidic acid, oxacillin, gentamicin, mupirocin, methicillin, and tobramycin; 0.0625 - 1024 mu g/mL) was screened individually and in combination against two S. aureus clinical strains (methicillin-resistant and-susceptible - MRSA and MSSA). The photodynamic activity of the phytochemicals was assessed using a lightemitting diode (LED) system with blue (420 nm) or UV-A (365 nm) variants, at 30 mW/cm 2 (light doses of 9, 18, 27 J/cm 2 ) and 5.5 mW/cm 2 (light doses of 1.5, 3.3 and 5.0 J/cm 2 ), respectively. Notably, all phytochemicals restored antibiotic activity, with 9 and 13 combinations exhibiting potentiating effects on MSSA and MRSA, respectively. Photodynamic activation with blue light (420 nm) resulted in an 8- to 80-fold reduction in the bactericidal concentration of berberine against MSSA and MRSA, while curcumin caused 80-fold reduction for both strains at the light dose of 18 J/cm 2 . Berberine and curcumin-antibiotic combinations when subjected to photodynamic activation (420 nm light, 10 min, 18 J/cm 2 ) reduced S. aureus culturability by approximate to 9 log CFU/mL. These combinations lowered the bactericidal concentration of antibiotics, achieving a 2048-fold reduction for gentamicin and 512-fold reduction for tobramycin. Overall, the dual approach involving antimicrobial photodynamic inactivation and selected phytochemical-antibiotic combinations demonstrated a synergistic effect, drastically reducing the culturability of S. aureus and restoring the activity of gentamicin and tobramycin.

Abstract This study presents the first investigation of the sublimation behavior of tin tetraiodide, SnI4, 4 , using effusion- based techniques, within a low temperature range (313-340) K. The temperature range covered in the experiments was lower than in previously reported studies based on static methods. Knudsen Effusion Mass Loss (KEML) measurements were performed in the range of (317.1-339.6) K using effusion cells with different orifice sizes. The vapor pressures were measured in the range (0.13-1.13) Pa and were found to be independent of the orifice size. The standard molar enthalpy and Gibbs energy of sublimation at 298.15 K obtained by the Clarke and Glew fit of experimental data are (88.1 +/- 0.9) kJ & sdot;mol-1 & sdot; mol- 1 and (38.96 +/- 0.08) kJ & sdot;mol-1, & sdot; mol- 1 , respectively. Knudsen Effusion Mass Spectrometry (KEMS) experiments were also performed in the range (313.3-331.7) K, resulting in a sublimation enthalpy value in good agreement with the KEML values and not negligibly higher vapor pressure values. KEMS vapor pressure data were also analyzed by the third-law method. A comparison of our experimental results with the literature data available for both sublimation and evaporation properties of SnI4 4 is reported. Additionally, ancillary DFT and ab initio calculations were performed to estimate the molecular properties of SnI4(g) 4 (g) and the extent of the gas-phase dissociation to SnI2 2 and I2. 2 .

Abstract Metallothioneins (MTs) and phytochelatins (PCs) are small Cys-rich proteins with low molecular mass responsible for detoxifying heavy metals in cells. Arabidopsis thaliana expresses eight metallothionein genes and two types of PCS; however, there is still a need to acquire more knowledge regarding their individual responses to some heavy metals. Thus, it was intended to study the expression of AtMT- and AtPCS1-encoding genes in response to high levels of nickel in wild-type A. thaliana. Seeds of A. thaliana were placed in MS medium supplemented with increasing concentrations of Ni-0 mg L-1, 2.5 mg L-1, 5 mg L-1, 7.5 mg L-1, and 10 mg L-1. After 21 days of exposure, the expression of the AtMTs (1A, 1B, 1C, 2A, 2B, and 3) and AtPCS1 was analysed through RT-qPCR in different plant organs: roots, young leaves, and mature leaves. The concentrations of photosynthetic pigments, hydrogen peroxide, and reduced glutathione were also evaluated, but no significant changes were observed. The gene expression analysis showed that the seven genes reacted differentially to the varying concentrations of Ni and in an organ-specific way. It was noted that in roots, the expression of AtMT1A, AtMT1C, and AtMT3 increased starting with the 2.5 mg L-1 treatment. At the same time, the response in the leaves fluctuated more as AtMT1B and AtMT1C increased in young leaves with concentrations higher than 7.5 and 2.5 mg L-1, respectively, with the remaining genes analysed having their expressions decreased starting with 7.5 mg L-1 of Ni. In mature leaves, AtMT1A increased, while AtMT2A, AtMT2B, and AtPCS1 decreased with Ni concentrations starting from 7.5 mg L-1. These results strongly suggest that the increase in the expression of AtMT1B, AtMT1C, and AtMT3 in the roots significantly reduced Ni toxicity, contributing to its local accumulation and buffering its translocation to the shoots. The overall reduction in the expression of MTs and PCS1 in leaves may be linked to the active participation of MT1A in mature leaves, while young leaves depended on the increased production of MT1B and MT1C to deal with the high amount of Ni present therein. These results contribute further knowledge to the understanding of the defence mechanisms of plants against high levels of Ni regarding the participation of MTs and PCS1.

Abstract Since ancient times, Aloe vera L. (AV) has attracted scientific interest because of its multiple cosmetic and medicinal properties, attributable to compounds present in leaves and other parts of the plant. The collected literature data show that AV and its products have a beneficial influence on human health, both by topical and oral use, as juice or an extract. Several scientific studies demonstrated the numerous biological activities of AV, including, for instance, antiviral, antimicrobial, antitumor, and antifungal. Moreover, its important antidepressant activity in relation to several diseases, including skin disorders (psoriasis, acne, and so on) and prediabetes, is a growing field of research. This comprehensive review intends to present the most significant and recent studies regarding the plethora of AV's biological activities and an in-depth analysis exploring the component/s responsible for them. Moreover, its morphology and chemical composition are described, along with some studies regarding the single components of AV available in commerce. Finally, valorization studies and a discussion about the metabolism and toxicological aspects of this Wonder Plant are reported.