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Essential oils (EO) obtained from plants have proven industrial applications in the manufacturing of perfumes and cosmetics, in the production and flavoring of foods and beverages, as therapeutic agents in aromatherapy, and as the active principles or excipients of medicines and pharmaceutics due to their olfactory, physical-chemical, and biological characteristics. On behalf of the new paradigm of a more natural and sustainable lifestyle, EO are rather appealing due to their physical, chemical, and physiological actions in human beings. However, EO are unstable and susceptible to degradation or loss. To tackle this aspect, the encapsulation of EO in microporous structures as zeolites is an attractive solution, since these host materials are cheap and non-toxic to biological environments. This overview provides basic information regarding essential oils, including their recognized benefits and functional properties. Current progress regarding EO encapsulation in zeolite structures is also discussed, highlighting some representative examples of essential oil delivery systems (EODS) based on zeolites for healthcare applications or aromatherapy., The authors are grateful for the national funds provided by the FCT (Foundation for Science and Technology, Portugal) under the projects UIDB/04050/2020 (CBMA) and PTDC/AAGTEC/5269/2014 (FEDER, European Fund for Regional Development)/COM PETE/POCI—Operational Competitiveness and Internationalization Programme under the project POCI-01-0145-FEDER-006958. They are grateful for the financial support provided by the Research Centers CQ/UM through UID/QUI/0686/2020 and Project BioTecNorte (operation NORTE-01-0145-FEDER-000004), supported by the Northern Portugal Regional Operational Programme (NORTE 2020) under the Portugal 2020 Partnership Agreement through the European Regional Development Fund., info:eu-repo/semantics/publishedVersion

The transport and storage of fruits is frequently compromised by microbial contaminations, especially during the delivery of these perishable foods to the public. The development of smart packages against microbial contaminations is an alternative of great interest to help controlling post-harvest diseases. The incorporation of nanomaterials, such as metal-ions zeolites with antimicrobial properties, in the semi-rigid alveolar structure for fruits transport/storage could allow the preservation of fruit with safety and quality, by inhibiting/reducing the growth of microrganisms. In this work, metal-ions zeolite nanomaterials were incorporated on the packaging material and the antibacterial activity was tested against Escherichia coli and Staphylococcus aureus. The package material exhibited good antimicrobial activity against the two bacteria (Figure 1), which are promising results for industrial application., info:eu-repo/semantics/publishedVersion

Recently, the application of zeolite structures in methanogenic communities has attracted significant attention, since they may enhance the anaerobic digestion process, by affecting specifically the methanogenic activity of the sludges1. Zeolites are solid inorganic crystalline materials comprised of silicon, aluminum and oxygen in the three-dimensional structure. The building blocks become arranged in a periodic way to form channels and cages on a nano- and subnanometer scale of strictly regular dimensions, named micropores. The presence of the aluminum in the zeolite framework create a negative charge in the lattice, which can be balanced by the exchangeable cations, as sodium or metal ions.2 In this study, commercial zeolite structures (ZSM5, USY, NaX and NaY) with different particle sizes and different exchangeable cations (Co, Cu, Zn, Fe) were used in order to investigate their effect towards the specific methanogenic activity, both acetoclastic and hydrogenotrophic, of anaerobic sludge. In the acetoclastic methanogenic activity, NaY modified with Cobalt (CoY) decreased the activity in comparison with the control (without zeolite). The remaining zeolites (ZSM5, USY, NaX and NaY), even when modified with metal ions (Zn, Fe, Cu), seems to have no effect on this methanogenic pathway. On the other hand, the hydrogenotrophic methanogenesis was improved by the presence of NaY (109 %), which did not happen in the presence of ZSM5 and USY zeolites. Additionally, the effect of different zeolite concentration was accessed. Overall, the increase of zeolite concentration from 1 g/L to 5 g/L resulted in a higher inhibition towards the methanogenic activity. In addition, the application of these nanomaterials can be evaluated in pure cultures of methanogens, in order to understand and fine-tune the best zeolite nanomaterial concentration that may improve the specific methanogenic activity., We thank the Fundação para a Ciência e Tecnologia (FCT) for financial support through Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and BioTecNorte (operation NORTE-01-0145-FEDER-000004), and through Centre of Biological -engineering (UIDB/04469/2020 unit). Cátia S. N. Braga holds a grant SFRH/BD/132003/2017 funded by FCT and European Union (EU), through the Portuguese State Budget and the European Social Fund under the scope of Programa Operacional Regional do Norte., info:eu-repo/semantics/publishedVersion

Water pollution is one of the most important environmental problems in the world. Large amounts of synthetic organic contaminants are released daily into different types of wastewaters and ultimately enter into natural water bodies. It is well known the vast majority of these compounds are persistent organic pollutants, owing to their high stability to sunlight irradiation and resistance to microbial attack. Advanced oxidation processes (AOPs) have been demonstrated to achieve good results for the elimination of organic pollutants from wastewater with very short treatment times. Fenton-type heterogeneous processes have received much attention for their low cost, high efficiency, and moderate conditions among these AOPs.1 In heterogeneous Fenton-type catalysis, iron (or other transition metals) is stabilized on/in the catalysts structure and thus can reduce hydroxide precipitation over a wider pH range.2 This work report the preparation of bimetallic heterogeneous catalysts based in NaY zeolite with Fe, Cu and Mn by ion-exchange method using different routes (Figure 1). Different characterization techniques show that the metals are cationic and show higher oxidation efficiency against the azo dyes, tartrazine and procion yellow, and the order of metal ion exchanging are important to improve their catalytic activity. The prepared bimetallic catalysts can be used at least three times without a significant loss of catalytic activity, proving to have a very high stability., We thank the Fundação para a Ciência e Tecnologia for financial support through Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and BioTecNorte (operation NORTE-01-0145-FEDER-000004), and the INAGBE (Instituto Nacional de Gestão de Bolsas de Estudo, Angola) for the PhD grant of BLCS., info:eu-repo/semantics/publishedVersion

The sol-gel process is a chemical synthesis often considered as a green technology due to mild conditions preparation since is waste-free and the processing temperature is generally low (e.g., close to room temperature). Also, uses compounds that do not introduce impurities into the end material and excludes the washing stage. Compared to other chemical routes, sol-gel method has several advantages in the design and synthesis of organic-inorganic hybrid (OIH) materials.1 This method allows the control of several experimental conditions leading to a simple sequence, which may be tuned to the nature, final shape, and according to a desired function. This route allows to obtain end products with high specific porosity and surface area which favours the introduction of materials complementary functionalities, such as UV protection, anti-fouling, anti-reflection, moisture resistance, corrosion and adhesion protection. Moreover, the low synthesis temperatures minimize the thermal volatilization and degradation of the entrapped species. Therefore, the introduction of supplementary functionalities together with the enhancement of the mechanical, thermal, and optical properties, opens a wide range of applications in numerous fields of science. This work reports the synthesis of OIH sol-gel matrices, which were obtained using a functionalized siloxane, 3-glycidoxypropyltrimethoxysilane, by reaction with an oligopolymer named JeffamineTHF 170.2 The OIH matrices were doped with different contents of AgY or NaY zeolites (i.e., 1, 3 and 5 wt%). The doped and undoped OIH matrices were characterized by different techniques namely Fourier-transform infrared spectroscopy, electrochemical impedance spectroscopy analysis, X-ray diffraction spectroscopy and scanning electron microscopy. Results obtained so far suggest that the introduction of AY or NaY enhance the stability of the hybrid sol-gel materials and could be explored as sensors., This research was funded by Operational Program Competitiveness and Internationalization (COMPETE 2020), the Lisbon Regional Operational Program (in its FEDER component), and by Foundation for Science and Technology (FCT), grant reference POCI-01-0145-FEDER-031220. The support of Centro de Química-UM through FCT project UID/QUI/00686/2019 is also acknowledged and BioTecNorte (operation NORTE-01-0145-FEDER-000004)., info:eu-repo/semantics/publishedVersion

Response Surface Methodology (RSM) was widely used in numerous research works for the optimization of different processes for liquid effluents treatment, since water pollution is one of the most serious environmental problem concerning human health and sustainability.1,2 RSM is a statistical technique applied to reduce the number of experiments, optimize and analyze the experimental independent parameters, that affect a process efficiency, and to generate a mathematical model which describes the process behavior.1,3 In this work, Box-Behnken design (BBD) was used for optimize the Fenton-type reaction using different bimetallic catalysts based in Rare Earth Elements with iron ion exchanged in zeolite (NaY) or a natural clay from Morocco. The effect of different experimental parameters such as, temperature, concentration of H2O2 and the heterogeneous catalysis used, was studied and optimized., We thank the Fundação para a Ciência e Tecnologia for financial support through Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and BioTecNorte (operation NORTE-01-0145-FEDER-000004), info:eu-repo/semantics/publishedVersion