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Actinomycetes produce secondary metabolites with many bioactivities such as antimicrobial, which can be useful as alternatives against resistant bacterial strains. Therefore, the screening of new habitats is likely to provide new strains with high potential. In this work, the antimicrobial capacity was used to select Streptomyces sp. strains isolated from Raf Raf forest (Tunisia). From the strain displaying higher activity, FR7, an ethyl acetate extract was prepared under optimized culturing conditions (10 days at 30°C in ISP2 medium with initial pH 8), showing significant antimicrobial activity against Micrococcus luteus and Staphylococcus aureus (MIC = 5 μg ml−1), and Listeria monocytogenes and Pseudomonas aeruginosa (MIC = 20 μg ml−1). The extract displayed strong DPPH radical scavenging activity (IC50 = 1.3 μg ml−1) and protection of yeast cells from H2O2-induced oxidative stress determined by flow cytometry with dichlorofluorescein diacetate. The crude extract showed the presence of polyketides, with methylsalicylic acid as moiety, a large and diverse group of secondary metabolites with a wide range of bioactivities, including antioxidant and antibacterial. Based on 16S RNA gene sequences, strain FR7 was identified as belonging to genus Streptomyces with high resemblance to S. iakyrus. Streptomyces sp. FR7 has great potential as a source of antibacterial and antioxidant metabolites.

Carbonation and corrosion of reinforced concrete structures (RCS) are the two main phenomena that more often affect civil engineering structures. The main consequence of carbonation is the pH reduction of concrete to values between 9 and 6 which may compromise the RCS durability. Thus, the development of sensors that would predict concrete carbonation is of utmost importance. Fiber optic sensors (OFS) are commonly used for concrete applications due to their high sensitivity and resistance to external interference. This work reports the synthesis of organic-inorganic hybrid (OIH) materials for possible functionalization of OFS and application in concrete and RCS. As precursors, 3-glycidyloxypropyltrimethoxysilane (GPTMS) and Jeffamine® THF-170 were used. The OIH sol-gel materials were doped with phenolphthalein (phph) for pH sensing proposes and cetyl trimethyl ammonium bromide (CTAB) as surfactant. OIH with pH sensing ability properties were successfully obtained and the doping of the OIH matrix did not significantly changed the dielectric properties of the resultant material. Moreover, the results obtained in simulated concrete pore solutions, obtained for the OIH produced, showed to be promising for application in fresh concrete. The transmittance of the synthesized OIH materials decreased after the doping. The matrix shows intrinsic fluorescence and doping it only led to small deviations in the wavelength of the peak of maximum emission. No significative changes were obtained on the thermal profile of the OIHs. The pH variation was shown by the OIH material color change. Stability studies regarding the release of phph from the OIH matrix indicates that the proposed system reveals long-term stability., Thanks are due to Fundaçã para a Ciência e Tecnologia (FCT) and FEDER (European Fund for Regional Development)-COMPETE-QRENEU for financial support through the Chemistry Research Centre of the University of Minho (Ref. CQ/UM (UID/QUI/00686/2019 and UID/QUI/00686/2020)), project “SolSensors — Development of Advanced Fiber Optic Sensors for Monitoring the Durability of Concrete Struc tures”, reference POCI-01-0145-FEDER-031220, a PhD grant to R. P. C. L. Sousa (SFRH/BD/145639/2019), a BSc grant to B. Ferreira and a Scientific Initiation grant to S. Sousa under the SolSensors project POCI 01-0145-FEDER-031220 is also acknowledged. Artur J. M. Valen tethanks the Coimbra Chemistry Centre and FCT for financial support (UID/QUI/00686/2020, UID/QUI/00313/2020).

The effect of different parameters such as temperature, type of catalyst and hydrogen peroxide (H2O2) concentration on the degradation of pollutants in water by Fenton-like oxidation was studied by using the Box-Behnken design (BBD), an effective statistical model to design the experiments. Concerning the heterogeneous catalysts, three bimetallic catalysts with lanthanum (La) and iron (Fe) ion-exchanged into zeolites (NaY and ZSM5) and a natural clay from Morocco were prepared and used for Fenton-like oxidation of organic pollutants in water. Tartrazine (Tar, a food coloring compound known as E102) and caffeine (Caf, a stimulant drug present in popular beverages such as coffee and tea) were selected as pollutants due to their presence in several commercial products for daily consumption. The BBD model indicated that the optimum catalytic conditions for Fenton-like reaction with an initial pollutant concentration of 30ppm at pH 3.0 were T=40°C and 90mM of H2O2. The maximum conversion values achieved with the best catalyst, LaFeZSM5, were 96.6% for Tar after 180min and 51.0% for Caf after 300min of reaction. To increase the conversion of Caf, a modified zeolite electrode was used for electro Fenton-like oxidation without H2O2, at room temperature., O.A. thanks to ERASMUS + Program for the mobility Ph.D. grant and O.B. thanks to Fundação para Ciência e Tecnologia, Portugal (FCT) for his Ph.D. grant (SFRH/BD/140362/2018).This research work has been funded by national funds funded through FCT/MCTES (PIDDAC) over the projects: LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), UIDB/04469/2020 (CEB) and by LA/P/0029/2020 (LABBELS), Centre of Chemistry (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 (ERDF)., info:eu-repo/semantics/publishedVersion

Preparation of new ironzeolite modified electrodes for the oxidation of pollutants via an electro-Fenton-like process is reported in this work. Alizarin Red S (ARS) is chosen as the model dye compound for anodic oxidation in an aqueous acidic medium. A minimal metal loading ranging from 0.2 to 0.8 wt% of ferrous/ferric (Fe2+/Fe3+) ions was introduced inside the ZSM-5 zeolite (Si/Al ratio of 15.0) via an ion-exchange process and the presence of iron species in the zeolite framework was determined using several physicochemical techniques. The ironzeolite samples obtained under different experimental conditions were employed in order to study the textural and structural properties, and electrocatalytic activity. Cyclic voltammetry measurements showed that the textural properties of zeolite do not mainly affect the electrocatalytic reaction. However, the differences observed in catalytic peaks were a consequence of different iron ions present in zeolite. The structurecatalytic activity relationship is highlighted by the identification of the degradation products like oxalic acid (C2H2O4) and formic acid (HCOOH). Consequently, the degradation of ARS reached an optimum value of ca. 30% at 2 V vs. SCE for Fe(iii)TTZSM-5 with a catalyst loading of 5.0 mg cm2. This study shows that ironzeolite modified electrodes are highly active for dye compound degradation without the addition of H2O2 and have potential application in the treatment of effluents., FCT (Fundação para a Ciência e a Tecnologia, Portugal) for the PhD grant to Marta Ferreira. This work was developed under the scope of the projects: 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 (ERDF). This work also has been funded by national funds (FCT), through the projects: PTDC/AAG-TEC/5269/2014, Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016). The authors also thank the graduate student João P. M. Fernandes for his contribution to the electrocatalytic tests., info:eu-repo/semantics/publishedVersion

During the treatment of acute lymphoblastic leukemia (ALL) with asparaginase (ASN) there is an accumulation of ammonia in the body as result of asparagine hydrolysis. This accumulation known as hyperammonemia is one of the main side-effects of this therapy. To avoid hyperammonemia is urgent to develop new strategies for ammonia retention. Herein is presented the immobilization of ASN into bovine serum albumin/poloxamer 407 (BSA/Pol407) nanoparticles. The ability of the developed nanoparticles to hydrolyze asparagine while retaining the forming ammonia is also explored. Different percentages of ASN were entrapped into BSA nanoparticles coated with Poloxamer 407 and were prepared by high-pressure homogenization. The nanoparticles were characterized regarding their physico-chemical properties, stability, capacity to retain ammonia and safety using zebrafish embryos as an in vivo model of toxicity. The BSA/ASN25%/Pol407 nanoparticles were selected as the best formulation to hydrolyze asparagine using the lowest nanoparticle concentration. These nanoparticles presented physical characteristics suitable for an intravenous application and were capable to retain the forming ammonia decreasing the negative effect of free ASN on zebrafish survival. These nanoparticles could potentially be used to prevent hyperammonemia during ALL treatment with ASN., This study was supported by FCT under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01- 0145-FEDER-006684) and BioTecNorte operation (NORTE-01-0145- FEDER-000004) and Nanotechnology Based Functional Solutions (NORTE-01-0145-FEDER-000019) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. We also acknowledge the strategic programme UID/BIA/04050/2013 (POCI-01-0145-FEDER-007569) funded by national funds through Fundação para a Ciência e a Tecnologia (FCT) and by the ERDF through the COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI). Marisa P. Sárria was supported by Marie Curie COFUND funding from the European Union’s 7th Framework Programme for research, technological development and demonstration under grant agreement 600,375. Artur Ribeiro and Ana Tinoco thanks FCT for funding the scholarships with the references SFRH/BPD/98388/2013, SFRH/BD/ 114035/2015, respectively., info:eu-repo/semantics/publishedVersion

Electrochemical oxidation, a powerful tool for the conversion of several of organic dye compounds using metal-exchanged zeolite modified electrodes, has shown great potential due to its capability of high efficiency degradation, a global priority for a sustainable environment. In this study, the role of the Fe(III)-exchanged-zeolite-modified electrodes using two different zeolite structures (such as FAU (Y) and MFI (ZSM-5)) on the Fenton-like oxidation of Congo Red dye (C32H22N6Na2O6S2) was investigated at room temperature. To clarify the electrocatalytic trend observed by constant potential electrolysis, the surface acidity of the catalysts prepared by ion-exchange method was determined by microcalorimetric measurements of ammonia adsorption. The different acid properties deriving from the presence of different cations (NH4+, H+ and Na+) in the case of MFI structure were found to enhance the ion-exchange capacity as well as the oxidation reaction. MFI catalysts - Fe(Na)ZSM-5, Fe(H)ZSM-5 and Fe(NH4)ZSM-5 - exhibited excellent activity and stability at the end of the electrolysis (within 60min), with a total dye degradation and an higher mineralization on Fe(H)ZSM-5 (64% of TOC), compared with Fe(Na)Ynano, which takes twice as long (120min) for total degradation, with 19% of TOC removal. This work provides an effective route for the development of stable Fe(III)-zeolite-modified electrodes for electro-Fenton oxidation, with a better stabilization of Fe3+ ions within the framework, without the aggregation of iron and the addition of H2O2, at room temperature., Z.B. thanks to ERASMUS+ Program for the mobility PhD grant. This research work has been funded by national funds funded through FCT/MCTES (PIDDAC), (Fundação para Ciência e Tecnologia, FCT) over the projects: LA/P/0045/2020 (ALiCE), UIDB/50020/2020 and UIDP/50020/2020 (LSRE-LCM), Centre of Chemistry (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 (ERDF)., info:eu-repo/semantics/publishedVersion

Surgicel® (regenerated oxidized cellulose) is a bio-absorbable hemostatic material widely applied to prevent surgery-derived adhesions. Some critical issues have been reported associated with this biomaterial, which we aimed to overcome by producing bacterial nanocellulose (BNC) membranes with hemostatic activity, through electrochemical oxidation using the tetramethylpiperidine-1-oxyl (TEMPO) radical. Samples were characterized by FTIR, NMR, SEM, XRD and their degree of polymerization. The oxidation degree was evaluated by titration of the carboxyl groups and the hemostatic behavior by whole-blood-clotting assays. In vitro and in vivo biodegradability of oxidized BNC membranes were evaluated and compared with that of Surgicel®. The oxidation degree increased from 4% to 7% and up to 15%, corresponding to an applied charge of 400, 700 and 1200 Coulombs, respectively. The oxidized BNC preserved the crystallinity and the 3D nano-fibrillar network, and demonstrated hemostatic activity, although not as effective as that of Surgicel®. In vivo assays demonstrated that the oxidized membranes did not induce an inflammatory response, revealing a good biocompatibility. However, non-degraded oxidized BNC was still detected at the implantation site after 56 days., This work was supported by the Fundação para a Ciência e Tecnologia (FCT), under the project BioTecNorte operation (NORTE01-0145-FEDER-000004), with funding by the European Regional Development Fund under the scope of Norte2020-Programa Operacional Regional do Norte. The authors gratefully give thanks to the project NORTE-08-5369-FSE-000012, with financial support of ESF—European Social Fund, under the scope of Norte2020—Programa Operacional Regional do Norte; and to UME-UTAD for the XRD analysis., info:eu-repo/semantics/publishedVersion

The electrochemical oxidation of diclofenac (DCF), a non-steroidal anti-inflammatory drug considered as an emerging pollutant (frequently detected in wastewater), was investigated on CNT, Pt/CNT and Ru/CNT modified electrodes based on Carbon Toray in aqueous media. The electroreactivity of DCF on these modified electrodes was studied using cyclic voltammetry and the kinetic parameters were calculated from the scan rate study. Cyclic voltammograms show several oxidation processes, which confirm the interaction between DCF and the catalyst surface necessary for direct oxidation processes. Constant potential electrolysis of DCF was carried out on carbon nanotubes (CNT) and metal supported CNT (M/CNT) modified electrodes, in 0.1 M NaOH and 0.1 M Na2CO3/NaHCO3 buffer media. The highest DCF conversion (88% after 8 h of electrolysis) was found in carbonate buffer medium, for Ru/CNT, while the best carbon mineralization efficiency (corresponding to 48% of the oxidized DCF) was obtained on Pt/CNT modified electrode in 0.1 M NaOH medium. The products of the electrolyses were identified and quantified by HPLC-MS, GC-MS, HPLC-UV-RID and IC. The results show the presence of some low molecular weight carboxylic acids, confirming the cleavage of the aromatic rings during the oxidation process., he authors thank FCT (Fundação para a Cência e a Tecnologia, Portugal) for the PhD grant of Marta Ferreira, and the financing of projects: PTDC/AAGTEC/5269/2014, Centre of Chemistry (UID-QUI/00686/2013 and UID/QUI/0686/2016), and LSRE-LCM (Base Funding – UIDB/50020/2020 of the Associate Laboratory LSRE-LCM – funded by national funds through FCT/ MCTES (PIDDAC)). This work has been developed under the scope of the projects 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 (ERDF). The authors also thank TUBITAK (Tu¨rkiye Bilimsel ve Teknolojik Aras-tirma Kurumu, operation TUBITAK-2219) for the post-doctoral grant to Dr Sevgi Gu¨ney., info:eu-repo/semantics/publishedVersion

Dye compounds are becoming a problematic class of pollutants for the environment, so it is important to develop stable catalysts for their elimination. First, several studies were performed with different Y zeolites (NaY, (NH4)Y and USY) in order to select the best support for the preparation of the bimetallic catalysts. In particular, NaY zeolite was used as the support for Fe, Cu and Mn metals to prepare mono and bimetallic Fenton-type catalysts by the ion exchange method. The catalysts were characterized by several techniques, such as chemical analysis, nitrogen physisorption, X-ray diffraction (XRD), scanning electron microscopy (SEM) and cyclic voltammetry studies. Characterization results revealed that the metals were successfully ion-exchanged within the NaY zeolite. The prepared catalysts were tested for the aqueous-phase degradation of dye compounds (Procion yellow (PY) and Tartrazine (Tar)) at atmospheric pressure and different temperatures, using H2O2 as the oxidant. All the investigated samples were found to be active in degrading the dyes through the Fenton-type process; however, the oxidation rate was found to be higher in the presence of the bimetallic catalysts. CuFe-NaY displays the best mineralization rate for PY oxidation while MnFe-NaY shows the highest activity for Tar degradation. This work may provide further insight into the design of Fenton-type bimetallic catalysts with improved catalytic properties for environmental remediation., This research work has been developed under the scope of the projects: 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 (ERDF). This work also has been funded by national funds (Fundação para Ciência e Tecnologia, FCT), through the projects: PTDC/AAGTEC/5269/2014, Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and Associate Laboratory LSRE-LCM-UIDB/50020/2020. OSGPS acknowledges FCT funding under the Scientific Employment Stimulus—Institutional Call CEECINST/00049/2018., info:eu-repo/semantics/publishedVersion

In the present study composites based on TiO(2 )nanoparticles, SiO2 and HY zeolite were synthesized by using a standard sol-gel methodology and analyzed by Fourier-transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy-energy-dispersive X-ray spectroscopy techniques. The photocatalysts were impregnated on cotton textiles and their photocatalytic abilities were examined by degradation of Rhodamine B (RhB) and Reactive Red 120 (RR120) dyes in aqueous solution under similar solar irradiation. RhB removal efficiencies from cotton textiles were 87%, 72% and 50% for TiO2, TiO2-SiO2-HY zeolite and TiO2-SiO2 composites, respectively and achieved after 3 h of light irradiation. However, for the RR120 dye, the reached result was different as the photodegradation for this dye (65% efficiency) was only observed in bare TiO2 functionalized textile. In addition, for the treatment with TiO2-SiO2-HY zeolite, it was found that for initial alkaline conditions at pH of the RhB dye solution, the photodegradation rate decreased., Salmon Landi Jr. thanks the Capes/Brazil for supports his Doctoral Fellowship (13346/13-0). The authors are also grateful to the financial support of the project "AIProcMat@N2020-Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020", with the reference NORTE-01-0145-FEDER-000006 and the project BioTecNorte (operation NORTE-01-0145FEDER-000004), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by ERDF through COMPETE2020-Programa Operacional Competitividade e Internacionalizacao (POCI), Project POCI-01-0145-FEDER-006984 - Associate Laboratory LSRELCM and by Portuguese funds through FCT-Fundacao para a Ciencia e a Tecnologia under the Strategic Funding UID/FIS/04650/2019 as well as project PTDC/AAGTEC/5269/2014 and Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016).

The most effective medicines available for the treatment of leishmaniasis, a life-threatening disease, exhibit serious toxicological issues. To achieve better therapeutic efficiency while decreasing toxicity associated with amphotericin B (AmB), water-soluble dextrin-AmB (Dex-AmB) formulations were developed. Self-assembled nanocomplexes were formed by dissolving Dex and AmB in alkaline borate buffer, followed by dialysis and either freeze-drying (FD) or nano spray-drying (SD), yielding water dispersible particles with a diameter of 214nm and 347nm, respectively. The very simple production process allowed the formation of amorphous inclusion complexes containing 14% of AmB in the form of monomers and water-soluble aggregates. Nanocomplexes were effective against parasites in axenic culture (IC50 of 0.056 and 0.096M for L. amazonensis and 0.030 and 0.044M for L. infantum, respectively for Dex-AmB FD and Dex-AmB SD) and in decreasing the intramacrophagic infection with L. infantum (IC50 of 0.017 and 0.023M, respectively for Dex-AmB FD and Dex-AmB SD). Also, the formulations were able to significantly reduce the cytotoxicity of AmB. Overall, this study demonstrates the suitability of dextrin as an AmB carrier and the facile and inexpensive development of a delivery system for the treatment of leishmaniasis., This work was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/ BIO/04469/2019 and BioTecNorte operation (NORTE-01-0145-FEDER000004 - Underpinning Biotechnology to foster the north of Portugal bioeconomy and NORTE-01-0145-FEDER-000012 - Structured program on bioengineered therapies for Infectious diseases and tissue regeneration) funded by the European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Ricardo Silva-Carvalho gratefully acknowledge FCT for the granted scholarship (SFRH/BD/118880/2016). Karoline Rachel Melo and Moacir Fernandes Queiroz gratefully acknowledge Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Brasil for the granted scholarship., info:eu-repo/semantics/publishedVersion

Electronic supplementary material The online version of this article (https://doi.org/10.1007/s00394-019-01915-8) contains supplementary material, which is available to authorized users., Purpose: The recognized biological properties of Ginkgo biloba extracts potentiate their utilization as an ingredient for functional foods. However, the digestive conditions can affect the chemical composition of the extracts and consequently their biological properties, which can lead to food safety problems. Thus, the impact of in vitro-simulated upper gastrointestinal tract digestion on the chemical composition and bioactivity of Ginkgo biloba leaf extract (GBE) was evaluated. Methods: Physicochemical conditions of human digestion were simulated in vitro, and its impact on the chemical composition of GBE was investigated by electrospray ionization-mass spectrometry. The persistence of bioactivity was investigated by subjecting GBE and the in vitro digested extract (DGBE) to the same methodology. Antioxidant properties were assessed using 2′,7′-dichlorofluorescein diacetate to measure the intracellular oxidation of Schizosaccharomyces pombe cells pre-incubated with GBE or DGBE and exposed to H2O2. Antigenotoxicity was tested by comet assay in HT-29 colon cancer cells pre-incubated with GBE or DGBE and challenged with H2O2. Results: The chemical analysis revealed a considerable change in chemical composition upon digestion. Pre-incubation with GBE or DGBE attenuated the H2O2-imposed intracellular oxidation in wild-type S. pombe cells, unlike the oxidative stress response-affected mutants sty1 and pap1, and decreased H2O2-induced DNA damage in HT-29 cells. The extracts did not induce toxicity in these eukaryotic models. Conclusion: The chemical composition of GBE was affected by in vitro digestion, but the antioxidant and antigenotoxic activities persisted. Therefore, G. biloba extract may be suitable for use as food additive and contribute to a healthy colon., This work is supported by European Investment Funds by FEDER/COMPETE/POCI—Operational Competitiveness and Internationalization Programme, under Project POCI-01-0145- FEDER-006958 and National Funds by FCT—Portuguese Foundation for Science and Technology, under the project UID/AGR/04033/2019. This work has also been funded by national funds through FCT - Fundação para a Ciência e a Tecnologia for Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016)., info:eu-repo/semantics/publishedVersion

Supplementary material related to this article can be found, in the online version, at doi:https://doi.org/10.1016/j.cattod.2019.06.039., The electrolysis of amoxicillin (AMX) was carried out on CNT, Pt/CNT and Ru/CNT modified electrodes based on Carbon Toray in 0.1 M NaOH, 0.1 M NaCl and 0.1 M Na2CO3/NaHCO3 buffer (pH 10) media with the aim of studying the significance of two factors, electrode material and pH, on the oxidative degradation and mineralization of AMX. For this purpose, the electrolysis products were identified by HPLC-MS and GC-MS, and quantified by HPLC-UV-RID and IC. The highest carbon mineralization efficiency, corresponding to 30 % of the oxidized AMX, was found for Pt/CNT modified electrode in carbonate buffer medium. Regarding to the AMX conversion, the results show that the effect of pH is higher than that of the electrode material. Principal component analysis allowed to determine the experimental parameters vs. product distribution relationship and to elucidate the oxidation pathways for the studied electrodes. The results show that the hydroxylation of the aromatic ring and the nitrogen atom play an important role on the efficient degradation of AMX., The authors thank FCT (Fundação para a Ciência e a Tecnologia) for the PhD grant of Marta Ferreira. This work has been developed under the scope of the projects: BioTecNorte (operation NORTE-01-0145- FEDER-000004) and “AIProcMat@N2020-Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020″, NORTE-01-0145-FEDER-000006, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by national funds (FCT/MCTES (PIDDAC)) through the projects: PTDC/AAGTEC/5269/2014, Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016) and Associate Laboratory LSRE-LCM - UID/EQU/50020/2019., info:eu-repo/semantics/publishedVersion

The decentralized production of bioelectricity as well as the bioremediation of contaminated sediments might be achieved by the incorporation of an anode into anaerobic sediments and a cathode suspended in the water column. In this context, a sediment microbial fuel cell microcosm was carried out using different configurations of electrodes and types of materials (carbon and stainless steel). The results showed a long-term continuous production of electricity (>300 days), with a maximum voltage of approximately 100 mV reached after ~30 days of operation. A twofold increase of voltage was noticed with a twofold increase of surface area (~30 mV to ~60 mV vs. 40 cm2 to 80 cm2), while a threefold increase was obtained after the substitution of a carbon anode by one of stainless steel (~20 mV to ~65 mV vs. 40 cm2 to 812 cm2). Cyclic voltammetry was used to evaluate sediment bacteria electroactivity and to determine the kinetic parameters of redox reactions. The voltammetric results showed that redox processes were limited by the diffusion step and corresponded to a quasi-reversible electron charge transfer. These results are encouraging and give important information for the further optimization of sediment microbial fuel cell performance towards the long-term operation of sediment microbial fuel cell devices., This study was supported by the Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2019 unit and BioTecNorte operation (NORTE-01-0145-FEDER-000004) funded by the European Regional Development Fund under the scope of Norte2020 — Programa Operacional Regional doNorte. The authors also acknowledge the fellowship awarded to Gilberto Martins (SFRH/BPD/80528/2011) under the scope of the program POPH/ESF., info:eu-repo/semantics/publishedVersion

This work reports the synthesis of nanocomposite photocatalytic materials based on nitrogen-doped TiO2nano, SiO2 and different percentages of HY zeolite (0, 12, 25 and 50%). These materials were characterized by using Fourier transformed infrared spectroscopy, X-ray diffraction, N2 adsorptiondesorption, UV-vis diffuse reflectance spectroscopy and scanning electron microscopy. The nanocomposites, which presented an energy band gap of about 3.03 eV, were immobilized on cotton fabric and their self-cleaning properties were investigated by decolourization of rhodamine B (RhB) dye in aqueous solution under simulated solar irradiation. The fabrics coated with the photocatalysts, containing and not containing zeolites, showed the same RhB decolourization (about 95%) after 5 h, excluding the situation where a large amount of HY (50%) was used in the nanocomposites. However, results obtained from high performance liquid chromatography analysis depicted that in the presence of the HY zeolite a more effective RhB degradation was achieved. In fact, even after the use of five consecutive cycles, the RhB decolourization remained high (about 85%). Generally, the photodegradation of RhB solution in the presence of cotton fabrics functionalized with TiO2nano, TiO2nano-SiO2 and TiO2nano-SiO2-0.25 HY resulted in the formation of products that exhibited a similar cytotoxic effect when compared to the untreated RhB solution and subjected to the same tested concentrations and incubation times., Salmon Landi Jr. thanks the Capes from Brazil for supports his Doctoral Fellowship (Proc. no. 13346/13-0). The authors are also grateful to the financial support of the project “AIProcMat@N2020 – Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, with the reference NORTE-01-0145-FEDER-000006 and the project BioTecNorte (operation NORTE-01-0145-FEDER-000004) supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by ERDF through COMPETE2020 – Programa Operacional Competitividade e Internacionalizac¸ão (POCI), Project POCI-01-0145-FEDER006984 – Associate Laboratory LSRE-LCM and by national funds through FCT – Fundac¸ão para a Ciência e a Tecnologia for project PTDC/AAGTEC/5269/2014 and Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016). Artur Ribeiro thanks FCT for the SFRH\BPD\98388\2013 grant., info:eu-repo/semantics/publishedVersion

The role of the nanostructured iron catalysts hosted by different type of zeolite structures (NaY and ZSM5) on the electrochemical degradation of Congo Red dye (C32H22N6Na2O6S2) was investigated. Here, the nano-iron zeolite catalysts with high surface areas (up to 853 m2 g-1) were prepared by ion-exchange method1 serving tunable particle size and acidity that is highly sensitive to the local reaction environment at the electrode surface. The structural and morphological analysis was carried out using scanning electron microscopy (SEM), X-ray diffraction and N2-sorption techniques. In order to clarify the electrocatalytic trend observed by constant potential electrolysis, we further considered the acidity properties of the zeolites determined by microcalorimetric measurements. Moreover, it was noted that the presence of NH4 +, H+ and Na+ ions in the case of ZSM5 zeolite allows the rearrangement of the iron-zeolite architecture, resulting in a more favorable stabilization of the degradation process as a function of the production rate. Compared with the FeNaY catalysts, the FeZSM5 catalysts (Fe(Na)ZSM5, Fe(H)ZSM5 and Fe(NH4)ZSM5) exhibited excellent activity and stability, with a maximum dye degradation around 64% on the Fe(H)ZSM5 catalyst. This work, revealing the synergetic interactions between the acid sites of the zeolite and the catalytic active sites, provides a new route for the development of electrochemical sensing low-metal content zeolite structures. Acknowledgements: This work was conducted in the framework of the BioTecNorte projects: NORTE-01-0145-FEDER-000004, PTDC/AAGTEC/5269/2014, UID/QUI/00686/2013, and UID/QUI/0686/2016. Z. B. is grateful for ERASMUS research grant. Reference: 1. M. Ferreira, F. Pinto, O. S. G. P. Soares, M. F. R. Pereira, J. J. M. Órfão, J. L. Figueiredo, I. C. Neves, A. M. Fonseca, P. Parpot, Chemical Engineering Journal, 228 (2013) 374.

The electroreactivity of amoxicillin (AMX) was studied on catalysts based on platinum, palladium and ruthenium supported on carbon nanotubes (Pt/CNT, Pd/CNT, Ru/CNT) in aqueous media using cyclic voltammetry. Cyclic voltammograms show two oxidation processes, the first one between 0.5 and 1.0 V vs. reference hydrogen electrode (RHE) and the second one between 1.2 and 1.6 V vs. RHE. The effects of electrocatalytic material and supporting electrolyte, on current intensities and oxidation potentials, were determined using experimental design strategy (DOE). Kinetic parameters of the oxidation reactions were calculated from the scan rate study. The constant potential electrolysis of AMX was carried out on Ru/CNT catalyst, in 0.1 M NaOH and AMX conversion reached 45 % after 6 h of electrolysis at 2.5 V vs. RHE. The percentages of CO32, SO42 and NO3 among oxidation products were 18, 15 and 2%, respectively. The primary degradation products of AMX determined by HPLCMS gave some insight about the reaction pathways., The authors thank FCT (Fundação para a Ciência e a Tecnologia) for the PhD grant of Marta Ferreira. This work is also a result of project BioTecNorte (operation NORTE-01-0145-FEDER-000004) and AIProcMat@N2020 (operation NORTE-01-0145-FEDER000006), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement through the European Regional Development Fund (ERDF). This work also has been funded by ERDF through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI), POCI-01-0145-FEDER-006984 – Associate Laboratory LSRE-LCM, and by national funds through FCT for PTDC/AAGTEC/5269/2014 and Centre of Chemistry (UID/QUI/ 00686/2013 and UID/QUI/0686/2016)., info:eu-repo/semantics/publishedVersion

The presence of two metals (M1M2) in a zeolite structure enhances the degradation of pollutants in liquid or gas phase comparing to monometallic catalysts. In this work, the complete oxidation of ethyl acetate into CO2 was achieved by metal catalysts based on NaY zeolite prepared by the ion-exchange method. The metal zeolite catalysts were optimized by used several parameters: (i) the presence of a second metal in M1M2 catalysts; (ii) the presence or not of a noble metal in the pair CuM2 (M2=Pd, Zn or Ag); (iii) the order of introduction of the metals in M1M2 catalysts (CuPd or PdCu); (iv) particle size of NaY and NaYnano; and (v) the effect of simultaneously adding metal species (Cu and Pd). M1M2 catalysts presented the best results compared to the monometallic catalysts and the presence of a noble metal in M1M2 catalysts enhanced their acivity. Among the metal phases studied, the catalyst (CuPd)0.01-Y was shown to be the most efficient for this application., This work has been developed under the scope of the projects: BioTecNorte (operation NORTE-01-0145-FEDER-000004) and “AIProcMat@N2020-Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, NORTE-01-0145FEDER-000006, supported by the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by national funds (FCT, Fundação para a Ciência e a Tecnologia), through the projects: PTDC/AAGTEC/5269/2014, Centre of Chemistry (UID/QUI/ 00686/2013 and UID/QUI/0686/2016) and LSRE/LCM (POCI-010145-FEDER-006984)., info:eu-repo/semantics/publishedVersion

The antimicrobial behavior of different pairs of bimetallic materials based on NaY zeolite was assessed in order to optimize the best metal pair composition. The materials were prepared by an ion-exchange method using zeolite Y in sodium form (NaY, 700 nm) with different metals (copper, zinc and silver). The resulting materials were characterized by Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), Fourier Transform Infrared spectroscopy (FTIR), cyclic voltammetry and chemical analysis, which indicated that the bimetallic metal species were effectively ion exchanged in NaY, with no modification of the zeolite structure. The antimicrobial potential of the materials was evaluated in vitro using the bacteria Escherichia coli and the yeast Saccharomyces cerevisiae as indicator strains. All materials showed good antimicrobial properties with the pair Zn/Ag being the most active among the bimetallic materials tested. The sequence of antimicrobial activities was as follows: Zn < inf > 0.05 < /inf > Ag-Y > AgZn < inf > 0.05 < /inf > -Y > AgCu-Y = CuAg-Y > Zn < inf > 0.05 < /inf > Cu-Y = CuZn < inf > 0.05 < /inf > -Y = NaY., The authors are grateful to FCT (Portuguese Foundation for Science and Technology) and FEDER (European Fund for Regional Development)-COMPETE-QREN-EU for financial support to the Research Centers CQ/UM - PEst-C/QUI/UI0686/2013 (F-COMP-01-0124-FEDER-037302) and project "n-STeP - Nanostructured systems for Tail", a NORTE-07-0124-FEDER-000039 supported by Programa Operacional Regional do Norte (ON.2) - and CITAB/UM (project UID/AGR/04033/2013)., info:eu-repo/semantics/publishedVersion

Reduced graphene oxide (RGO) and titanium dioxide (TiO2) nanoparticles were immobilized on cotton textile substrates to produce self-cleaning textiles. Varying number of layers of RGO andTiO(2) nanoparticles were coated by a facile method, and their photocatalytic potential was evaluated by measuring the degradation rate of rhodamine B (Rh-B) in an aqueous solution in a photoreactor under simulated solar irradiation. X-ray diffraction (XRD) and zeta potential measurements of starting materials were studied as they are crucial for innovative methods of functionalization. The study confirms that it is possible to ensure a good adhesion of nanoparticles on textile samples without the use of a resin. The application of varying number of RGO and TiO2 coatings has influence on photocatalytic properties of functionalized cotton textile substrates. The energy band gap of the samples reduces from 3.25 to -3.20 eV with the number of RGO coatings. All five de-ethylated intermediates of Rh-B during the photocatalytic degradation were identified using a high-performance liquid chromatography-mass spectrometry method. The experimental results show that, in general, the higher the number of RGO coatings is, the higher the photocatalytic efficiency (eta) of the functionalized substrate is (eta= 87% for three RGO coatings on TiO2)., S. Landi Jr. expresses his gratitude to the Brazilian Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) for sporting his Doctoral Fellowship performed in Physics Centre at University of Minho. J. Molina wishes to thank the Spanish Ministerio de Ciencia e Innovacion (contract CTM2011-23583) for the financial support. Moreover, the authors still want to thank the Portuguese Foundation for Science and Technology (FCT) for its contribution in financial support of this research work., info:eu-repo/semantics/publishedVersion

This work is devoted to study the photocatalytic ability of cotton textiles functionalized with SiO2-TiO2 and SiO2-TiO2-HY composites to degrade a dye molecule. Coatings were prepared by sol-gel method and calcined at different temperatures in a range of 400–750 °C. FTIR confirmed the existence of SiOTi bounds and the band located in the region between 570 and 600 cm−1 was used to calculate the framework Si/Al ratio of HY in the SiO2-TiO2-HY composites. XRD confirmed the presence of nanosized TiO2 (anatase phase) in all calcined composites. Nitrogen adsorption isotherms showed a decrease in surface area and pore volume for higher calcination temperature. A simple mechanical process was used to impregnate the different composites on the cotton substrates. The photocatalytic activity of cotton textiles functionalized with SiO2-TiO2 and SiO2-TiO2-HY composites was tested via the degradation of Rhodamine B (RhB) dye under similar solar irradiation. The best catalytic performance was achieved with the SiO2-TiO2 and SiO2-TiO2-HY composites subjected to a calcination treatment at 400 °C, whereas SiO2-TiO2 presented a decolourization and mineralization around 94% and 89%, respectively, after 2 h of irradiation. Furthermore, the products of RhB degradation were analysed and identified by using HPLC-ESI–MS and ion chromatography techniques and a photocatalytic mechanism was proposed., The authors thank CAPES from Brazil for the financial support of this work. This work is also a result of project “AIProcMat@N2020 − Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, with the reference NORTE-01-0145-FEDER-000006 and the project BioTecNorte (operation NORTE-01-0145-FEDER-000004), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF). This work also has been funded by ERDF through COMPETE2020 − Programa Operacional Competitividade e Internacionalização (POCI), Project POCI-01-0145-FEDER-006984 − Associate Laboratory LSRE-LCM and by national funds through FCT − Fundacão para a Ciência e a Tecnologia for project PTDC/AAGTEC/5269/2014 and Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016)., info:eu-repo/semantics/publishedVersion

Several silica microporous structures have been studied for their potential as drug delivery systems (DDS) over the last years. However, systematic studies comparing host structures with different topologies and particle sizes, and toxicity studies to human cancer cells, are scarce. In the present work, 3D crystalline structures, three different zeolites (large, medium and small pore size) and one titanosilicate (large pore size) were used as hosts for loading 5-fluorouracil (5-FU), an anticancer drug currently used to treat several malignant tumors. Here, we (i) compared the loading capacity and drug release profiles of the different hosts in simulated body fluid conditions, including host structure stability studies; (ii) established the kinetic parameters for the release of 5-FU and (iii) studied the effect of 5-FU encapsulation in the viability of human breast and colon cancer cells, with determination of the potentiation factor. The loading capacity and the release profile of the DDS were revealed to be dependent on the porous framework of the host structures. Decrease in pH to 2.0 (simulation of gastro-intestinal fluid), showed stability of the host structures, with minimal leaching of Al3+ and no Ti4+ for long periods of time (up to 72 h). All DDS drug release profiles fitted the Weibull model. These silica microporous structures were revealed to be non-toxic to the cancer cells, while all DDS endorsed the important 5-FU potentiation effect on cell viability., N. V., F. M. S. and R. A. are recipients of PhD fellowships (SFRH/BD/97797/2013, SFRH/BD/87139/2012 and SFRH/BD/98002/2013) from Foundation for Science and Technology (FCT, Portugal). MS also acknowledges FCT for a post-doc grant (SFRH/BPD/65978/2009). This work has been developed under the scope of the project NORTE-01-0145-FEDER-000013 and the 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 (FEDER). This work also has been funded by national funds (FCT), through the projects: Centre of Chemistry (UID/QUI/00686/2013 and UID/QUI/0686/2016); CICECO (PEst-C/CTM/LA0011/2013, F-COMP-01-0124-FEDER-037271); LSRE/LCM (POCI-01-0145-FEDER-006984) and ICVS/3B's (POCI-01-0145-FEDER-007038)., info:eu-repo/semantics/publishedVersion

There has been a growing interest for the sustainable production of formic acid (FA) in recent years considering its potential use as a hydrogen storage compound. In this context, the electrochemical transformation of carbohydrate-based biomass into formic acid in aqueous media was investigated using a filter-press type electrochemical cell. Therefore the oxidation of mono and disaccharides was carried out at NiOOH, RuO2/Ti (DSA) and PbO2 anodes, in FM01-LC (ICI) electrolyzer. The effect of carbon number of biomass compound, anode material and pH on product distribution was determined. Between the readily available carbohydrates studied in this work at NiOOH anode, in alkaline medium, d -xylose provides the highest selectivity towards formate anion, i.e. 42%. The transformation of d -glucose into formic acid, with 38% selectivity, was achieved at RuO2/Ti (DSA) in 0.5 M NaOH medium, applying a current density of 80 A m−2. The production of formate anion is mostly accompanied by the formation of oxalate anion and carbonates which constitute the by-products of the reaction. Considering that after acidification of carbonates the resulting CO2 can be easily removed and trapped by the growing plants which provide new biomass-based material, the transformation of oxalate anion (OA) into CO32− is of major importance. For this reason the oxidation of OA at DSA in 0.1 M NaOH medium was also studied. In these conditions 60% of the initial oxalate anion was transformed to CO32− at 2.5 V vs. SCE.

A very compact flat microbial fuel cell (MFC), with 64 cm2 each for the anode surface and the cathode surface and 1 cm3 each for the anode and cathode chambers, was tested for wastewater treatment with simultaneous electricity production with the ultimate goal of implementing an autonomous service in decentralized wastewater treatment systems. The MFC was operated with municipal wastewater in sequencing batch reactor mode with re-circulation. Current densities up to 407 W/m3 and a carbon removal of 83% were obtained. Interruption in the operation slightly decreased power density, while the re-circulation ratio did not influence power generation. The anode biofilm presented high conductivity, activity and diversity. The denaturing gradient gel electrophoresis band-pattern of the DNA showed the presence of several ribotypes with different species of Shewanellaceae and Geobacteraceae families., The authors are indebted to their colleagues at Frossos Wastewater Treatment Plant (Braga, Portugal) for providing wastewater samples. This work has been supported by the European Commission, through the Programme LIFE+ and the project WW4ENVIRONMENT (LIFE08 ENV/P/00237). The authors also acknowledge the Grant SFRH/BD/38331/2007 from the FCT/MCTES, Portugal, awarded to Luciana Peixoto.

Constant current and constant potential electrolyses of oxalic and oxamic acids were carried out on multiwalled carbon nanotubes (CNT) and on monometallic (Pd and Pt) and bimetallic (Ru–Cu) catalysts supported on multiwalled carbon nanotubes. Both carboxylic acids were mineralized with high conversions via hypochlorite ion produced in situ, in 0.10 M NaCl medium. Highest current efficiency, corresponding to 97%, and highest reaction rate constant for oxalic acid mineralization were obtained for the Ru–Cu/CNT modified electrode, in 0.10 M NaCl medium. The mineralization of oxamic acid was achieved with a faradic yield of 96% and an energy consumption of 14.6 kWh (kg of pollutant)−1in the same medium. The conversion values obtained for the oxidation of oxalic acid in 0.50 M NaOH medium, on Pt/CNT, Pd/CNT and Ru–Cu/CNT modified electrodes, were respectively 42%, 60% and 85%. In this last medium, 88% of the initial oxamic acid (15.8 mM) was transformed to carbonate ion and nitrogen at Pt/CNT modified anode.

The manganese(III) complex with a Schiff-base salen-type ligand (1,5-bis{[(1E)-(2-hydroxyphenyl)methylene]amino}-1H-imidazole-4-carbonitrile) has been encapsulated in the nanopores of a Y zeolite by using two different methodologies, the flexible ligand and in situ complex preparation methods. Cyclic voltammetry studies revealed that the neat complex undergoes reversible oxidation in dmf, which has been attributed to the MnII/III redox couple, whereas the two heterogeneous catalysts show different electrochemical behaviour in aqueous medium. The encapsulated and non-encapsulated homogeneous MnIIIsalen complexes were screened as catalysts for olefin oxidation by using tBuOOH as the oxygen source in different solvents. Under the optimized conditions, the catalysts exhibited moderate activity. Both heterogeneous catalysts catalysed the oxidation of cyclohexene with tBuOOH, primarily to give the allylic oxidation products. These catalysts were found to be reusable after the catalytic cycle, but with some loss of activity. A DFT study confirmed the distortion of the complex in the zeolite cage, the main difference being observed for the bonded chloride., I. K.- B. thanks the Fundacao do Ministério de Ciência e Tecnologia (FCT) for a contract under the program Ciência 2007. The authors thank the FCT and the Fundo Europeu de Desenvolvimento Regional (FEDER)) [COMPETE-QREN-EU, grant number PEst-C/QUI/UI0686/2011 (FCOMP-01-0124-FEDER-022716)] for financial support to the Research Centre at the Centro de Quimica, Universidade do Minho.

"Published online: 17 June 2016", Asparaginase reduces the levels of asparagine in blood, which is an essential amino acid for the proliferation of lymphoblastic malign cells. Asparaginase converts asparagine into aspartic acid and ammonia. The accumulation of ammonia in the bloodstream leads to hyperammonemia, described as one of the most significant side effects of asparaginase therapy. Therefore, there is a need for asparaginase formulations with the potential to reduce hyperammonemia. We incorporated 2 % of therapeutic enzyme in albumin-based capsules. The presence of asparaginase in the interface of bovine serum albumin (BSA) capsules showed the ability to hydrolyze the asparagine and retain the forming ammonia at the surface of the capsules. The incorporation of Poloxamer 407 in the capsule formulation further increased the ratio aspartic acid/ammonia from 1.92 to 2.46 (and 1.10 from the free enzyme), decreasing the levels of free ammonia. This capacity to retain ammonia can be due to electrostatic interactions and retention of ammonia at the surface of the capsules. The developed BSA/asparaginase capsules did not cause significant cytotoxic effect on mouse leukemic macrophage cell line RAW 264.7. The new BSA/asparaginase capsules could potentially be used in the treatment of acute lymphoblastic leukemia preventing hyperammonemia associated with acute lymphoblastic leukemia (ALL) treatment with asparaginase., Fundação para a Ciência e a Tecnologia - SFRH\BPD\98388\2013 ; UID/BIO/04469/2013 ; UID/BIA/04050/2013, COMPETE 2020 (POCI-01-0145-FEDER-006684)

In recent years, new textile materials have been developed through the use of nanotechnology-based tools. The development of textile surfaces with self-cleaning properties has a large combined potential to reduce the environmental impact related to pollution. In this research work, three types of textiles substrates (cotton, Entretela, and polylactic acid (PLA)) were functionalized with titanium dioxide nanoparticles (TiO2) using chemical and mechanical processes (padding). During the functionalization process, two different methods were used, both of which allowed a good fixation of nanoparticles of TiO2 on textile substrates. The samples were examined for morphology and for photocatalytic properties under visible light irradiation. A study aimed at evaluating the effect of pH of the aqueous solution of TiO2 nanoparticles was performed in order to promote interaction between TiO2 and the dye solution rhodamine B (Rh-B). The TiO2 nanoparticles were characterized by X-ray diffraction (XRD). The measurement of the zeta potential of the TiO2 nanoparticle solution proved to be always positive and have low colloidal stability. Chromatography (HPLC and GC-MS) analyses confirmthat oxalic acid is the intermediate compound formed during the photodegradation process., The authors would like to acknowledge FCT—Fundacão para a Ciência e Tecnologia—for funding under the Project PTDC/FIS/120412/2010, “NanoEcoBuild: Nanobased concepts for Innovative&Eco sustainable Constructive Material’s Surfaces,” and the European Commission through FP7 PEOPLE-2010-IRSES-NanoCIS(269279) project., info:eu-repo/semantics/publishedVersion

Phenol was successfully oxidized by the heterogeneous catalysts based on iron(II) or copper(II) pyrrolylazine complexes encapsulated into NaY zeolite, under mild conditions. The heterogeneous catalysts were prepared using two different methods and characterized by different spectroscopic techniques and chemical analysis. The pyrrolyl-azine complexes are formed with a metal/ligand molar ratio of 2:1. Their structures were further confirmed by OFF calculations. The catalytic experimental conditions (e.g., amount of catalyst, presence or absence of the oxidant, PhOH:tBuOOH molar ratio) were optimized. The presence of the encapsulated metal pyrrolyl-azine complexes in NaY zeolite enhances higher conversion of phenol to catechol. The catalytic activities of the encapsulated metal complexes in NaY zeolite were compared with the homogeneous counterpart, and the catalysts were easily recovered and reused., IKB thanks to Foundation for the Science and Technology (FCT, Portugal), for the contract under 'Programa Ciencia 2007 and for the contract under the project "n-STeP - Nanostructured systems for Tail" (NORTE-07-0124-FEDER-000039, supported by Programa Operacional Regional do Norte (ON.2). FCT and FEDER (European Fund for Regional Development)-COMPETE-QREN-EU for financial support to the Research Centres, MUM [PEst-C/QUI/UI0686/2013 (F-COMP-01-0124-FEDER-037302) and project NORTE-07-0124-FEDER-000039. This work is funded also by FEDER funds through the Operational Programme for Competitiveness Factors COMPETE and by National Funds through FCT - Foundation for Science and Technology under the grant PEST-C/EQB/LA0006/2013/37285. FCT is also acknowledged for financial support to the NMR Portuguese network (PTNMR, Bruker Avance III 400-Univ. Minho). Also, the authors are grateful to Dr A. S. Azevedo for collecting the powder diffraction data., info:eu-repo/semantics/publishedVersion

The present work explores the best conditions for the enzymatic synthesis of poly (ethylene glutarate) for the first time. The start-up materials are the liquids; diethyl glutarate and ethylene glycol diacetate, without the need of addition of extra solvent. The reactions are catalyzed by lipase B from Candida antarctica immobilized on glycidyl methacrylate-ter-divinylbenzene-ter-ethylene glycol dimethacrylate at 40 °C during 18 h in water bath with mechanical stirring or 1 h in ultrasonic bath followed by 6 h in vacuum in both the cases for evaporation of ethyl acetate. The application of ultrasound significantly intensified the polyesterification reaction with reduction of the processing time from 24 to 7 h. The same degree of polymerization was obtained for the same enzyme loading in less time of reaction when using the ultrasound treatment. The degree of polymerization for long-term polyesterification was improved approximately 8-fold due to the presence of sonication during the reaction. The highest degree of polymerization achieved was 31, with a monomer conversion of 96.77%. The ultrasound treatment demonstrated to be an effective green approach to intensify the polyesterification reaction with enhanced initial kinetics and high degree of polymerization., This study was supported by Portuguese Foundation for Science and Technology (FCT) under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684). The work was also supported by Bioprocess and Bionanotechnology Research Group (BBRG) of Minho University and the Post Graduate Funding Program of Jiangnan University for Overseas Study. All authors also acknowledge the funding of Department of Science and Technology and Portuguese Science Foundation under the Indo-Portuguese collaborative program.

This study investigates the functionalization of titanium dioxide nanoparticles on the surface of polymeric microcapsules as a mean to control the release of encapsulated citronella through solar radiation. This allows for the release of a mosquito repellent without human intervention, as the sunlight works as a release activator. The TiO2 nanoparticles were synthetized using a modified sol–gel and hydrothermal method, with a crystallite size of the order of 10 nm and a specific surface area >250 m2/g. Transmission electron microscopy observations enabled the confirmation of the mesoporous structure. The nitrogen doping effect and changes in pH (pH = 3, 6 and 9) of the precursor solution was studied from photocatalytic and photoluminescence experiments. Polyurethane microcapsules were prepared using a modified interfacial polymerization method. The surface topography ofthe microcapsules was observed with scanning electron microscopy, while the release efficiency was quantified using gas chromatography coupled with mass spectroscopy. In-vitro bioassays using live mosquitoes further attested the controlled release repellence effect of these photocatalytic microcapsules by inhibition of these vectors. The results showed that functionalizing the microcapsules with nanoparticles on their surface and then exposing them to ultraviolet radiation effectively increased the output of citronella into the air, repelling the mosquitoes, This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the PTDC/CTM-NAN/119979/2010 project. Juliana Marques acknowledges the FCT supportfor her PhD grant SFRH/BD/112868/2015. The authors would like to acknowledge Dr C. Mateos-Pedrero for the BET surface area analysis.

Peroxidases can be used in decolorization processes and the treatment of textiles effluents. This study evaluates the potential of the turnip peroxidase enzyme in the decolorization of the phthalocyanine textile dye Reactive Blue 21 (RB21). Some factors such as pH, the amount of H2O2 and the enzyme were evaluated in order to determine the optimum conditions for the enzyme performance. The reaction products formed during the decolorization of the RB21 dye were analyzed by high-performance liquid chromatography–mass spectrometry coupling (LC–ESI/MS). LC–ESI/MS analysis showed that the decolorization of the dye RB21 by turnip peroxidase is due to the breaking up of the chromatogenous system. The tests for toxicity towards lettuce seeds showed an increase of the toxicity after enzymatic treatment of the dye. This study verifies the viability of the use of the turnip peroxidase enzyme in the biodegradation of textile dyes., FAPEMIG, CNPq, CAPES

The electrochemical oxidation of oxalic and oxamic acids on multiwalled carbon nanotubes (CNT) and on monometallic (Pd and Pt) and bimetallic (Pd-Cu, Pt-Cu) catalysts supported on multiwalled carbon nanotubes was investigated using cyclic voltammetry. The electrodes were prepared by dispersion of the catalytic material on Toray carbon (CT) using a Nafion/water solution. The kinetic parameters of the reactions were determined using cyclic voltammetry. Modification of Toray carbon electrode with carbon nanotubes enables the oxidation of oxalic and oxamic acids in the solvent stability region. The highest oxidation current densities were observed for the Pt-Cu/CNT/CT electrode in 0.1 M NaCl. The oxidation potentials for both oxalic and oxamic acids in this case were lower than those observed with the CNT/CT electrode. The prepared electrocatalysts show good mechanical and chemical stability., Support for this work was provided by the project NANO/NTec-CA/0122/2007 financed by Fundacao para a Ciencia e a Tecnologia (FCT), Portugal and FEDER, in the context of Programme COMPETE.

The concentrations of all components in the phases of aqueous two-phase polyethylene glycol–sodium sulfate system of a fixed composition with different concentrations of NaCl additive were determined. Solvatochromic solvent features of aqueous media in the phases of all the systems were characterized in terms of solvent dipolarity/polarizability, solvent hydrogen bond donor acidity and hydrogen bond acceptor basicity. Partitioning of a homologous series of dinitrophenylated amino acids with aliphatic alkyl side chain was examined in all the systems, and the differences between the relative hydrophobicity and electrostatic properties of the phases were quantified. These differences were described in terms of solvatochromic solvent features of the phases. The previously reported partition coefficients of twelve different nonionic compounds in all the systems were expressed in terms of solute descriptors. It is demonstrated that two solvatochromic solvent descriptors (solvent dipolarity/polarizability, and solvent hydrogen bond donor acidity) could adequately describe the partitioning of the solutes in all the systems employed., Luisa A. Ferreira acknowledges the financial support (SFRH/BPD/47607/2008) from Fundacao para a Ciencia e a Tecnologia (Lisboa, Portugal).

The oxidation of some readily available carbohydrates was investigated in aqueous medium using a catalytic amount of 2,2,6,6-Tetramethyl-1-piperidinyl-oxy (TEMPO) as redox mediator. The regeneration of oxoammonium (active form) was electrochemically performed in alkaline medium at a glassy carbon anode and at controlled potential (0.5 V vs. AgCl/Ag). The primary alcohol groups of the carbohydrates without free aldehyde group, were selectively oxidized to the corresponding sodium uronate with high Faradaic yields. The presence of free aldehyde or hemiacetal groups leads to a decrease in selectivities towards uronic acids and increases the amount of by-products.

The electroactivity of zeolite-encapsulated redox-active transition metal complexes was explored for copper(II)-PAN (PAN = 1-(2-pyridylazo)-2-naphthol) complex encaged in the supercages of Y zeolite. Copper(II)-PAN complex and the zeolite boundary were investigated electrochemically by dispersion with a Nafion/water solution on carbon Toray as supporting electrode. Encapsulation was achieved by: (i) ion exchange of copper(II) in NaY zeolite and (ii) coordination of the intrazeolite metal ion with the PAN ligand using an L:copper(II) molar ratio of 2:1. The resulting materials were characterized by cyclic voltammetry in zeolite modified electrodes, surface analysis (XPS, SEM and XRD), spectroscopic methods (EPR and FTIR) and chemical analysis, which indicated that the copper(II)-PAN complex was effectively encapsulated inside the supercages of NaY, without any modification of the morphology and structure of the zeolite. The coordination geometry of Y-encapsulated copper(II)-PAN complex has been obtained with preferentially 1:1 stoichiometry analogous to the model complex, [CuCl(PAN)], by molecular simulations. For the cyclic voltammetry studies, the electrochemical behavior of free complex was compared with copper(II)-PAN complex encapsulated in Y zeolite. The results show evidence for electroactivity restricted to the boundary associated to the copper(II)-PAN complex.

The oxidation of d -mannose is studied on platinum, gold and nickel in alkaline medium. The electro-reactivity of this compound and the rate determining step of the reactions were determined by cyclic voltammetry. Lead adatoms have important effect on the oxidation of d -mannose on platinum electrode. Five folder of increase in current densities was observed after the addition of 10−6 M Pb2+. Electrolyses carried out on upd-lead modified platinum, and gold electrodes show good conversion yields (75% and 80%, respectively) and reasonable selectivities towards mannonic acid. High amount of cleavage products were detected at the end of the electrolysis at nickel electrode. The reactivity-functional group relationship has been discussed considering the results of the electrolyses.