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The aim of this study was to evaluate tetracycline antibiotic (TA) removal from contaminated water by Moringa oleifera seed preparations. The composition of synthetic water approximate river natural contaminated water and TA simulated its presence as an emerging pollutant. Interactions between TA and protein preparations (extract; fraction and lectin) were also evaluated. TA was determined by solid phase extraction followed by high performance liquid chromatography - mass spectrometry. Moringa extract and flour removed TA from water. Extract removed TA in all concentrations and better removal (40%) was obtained with 40 mg L1; seed flour (particles < 5mm), 1.25 g L1 and 2.50 g L1 removed 28 and 29% of tetracycline, respectively; particles > 5 mm (0.50 g L1) removed 55% of antibiotic. Interactions between TA and seed preparations were assayed by haemagglutinating activity (HA). Specific HA (SHA) of extract (pH 7) was abolished with tetracycline (5 mg L1); fraction (75%) and lectin HA (97%) were inhibited with TA. Extract SHA decreased by 75% at pH 8. Zeta potential (ZP) of extract 700 mg L1 and tetracycline 50 mg L1 , pH range 5 to 8, showed different results. Extract ZP was more negative (10.73 mV to 16.00 mV) than tetracycline ZP (0.27 mV to 20.15 mV); ZP difference was greater in pH 8. The focus of this study was achieved since moringa preparations removed TA from water and compounds interacting with tetracycline involved at least lectin binding sites. This is a natural process, which do not promote environmental damage., This work was supported by the Fundacao para a Ciencia e a Tecnologia and POPH/FSE under Grant SFRH/BPD/37349/2007; the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for fellowships (PMGP and LCBBC); the authors thank the FCT Strategic Project of UID/BIO/04469/2013 unit, the project RECI/BBB-EBI/0179/2012 [FCOMP-01-0124-FEDER-027462] and the project 'BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes,' REF. NORTE-07-0124-FEDER-000028 Co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER.

The electrochemical mineralization of aniline, a compound that causes serious environmental problems, was investigated at Pt, Pd and Ru-Cu catalysts supported on multiwalled carbon nanotubes (CNTs). The modified electrodes, based on commercial CNT samples, were prepared and dispersed onto Toray carbon (CT) using a Nafion/water solution. The electroreactivity of aniline at the electrocatalysts based on CNTs, and the kinetic parameters of the redox reactions, were determined using cyclic voltammetry. In order to determine the conditions that allow an efficient mineralization, the electrochemical oxidation of aniline was carried out in a membrane separated electrochemical cell. The reaction products were identified and quantified using chromatographic methods in order to evaluate the mineralization efficiency. The highest conversions were obtained with the Ru-Cu/CNT/CT modified electrode., O.S.G.P. Soares acknowledges FCT for grant SFRH/BPD/80435/2011. The LCM group acknowledges the support by PEst-C/EQB/LA0020/2013, financed by FEDER through COMPETE – Programa Operacional Factores de Competitividade, and by FCT – Fundação para a Ciência e a Tecnologia; NORTE-07-0124-FEDER-0000015 and NORTE-07-0162-FEDER-000050, financed by QREN, ON2 and FEDER. This work was also supported by the Centre of Chemistry (University of Minho, Portugal), through the projects PEst-C/QUI/UI0686/2013 (F-COMP-01-0124-FEDER-037302) and n-STeP Project, reference NORTE-07-0124-FEDER-000039, supported by the Programa Operacional Regional do Norte (ON.2)., info:eu-repo/semantics/publishedVersion

The potential of salicylic acid (SA) encapsulated in porous materials as drug delivery carriers for cancer treatment was studied. Different porous structures, the microporous zeolite NaY, and the mesoporous SBA-15 and MCM-41 were used as hosts for the anti-inflammatory drug. Characterization with different techniques (FTIR, UV/vis, TGA, 1H NMR, and 13C CPMAS NMR) demonstrated the successful loading of SA into the porous hosts. The mesoporous structures showed to be very efficient to encapsulate the SA molecule. The obtained drug delivery systems (DDS) accommodated 0.74 mmol (341 mg/gZEO) in NaY and 1.07 mmol (493 mg/gZEO) to 1.23 mmol (566 mg/gZEO) for SBA-15 and MCM-41, respectively. Interactions between SA molecules and pore structures were identified. A fast and unrestricted liberation of SA at 10 min of the dissolution assay was achieved with 29.3, 46.6, and 50.1 µg/mL of SA from NaY, SBA-15, and MCM-41, respectively, in the in vitro drug release studies (PBS buffer pH 7.4, 37 °C). Kinetic modeling was used to determine the release patterns of the DDS. The porous structures and DDS were evaluated on Hs578T and MDA-MB-468 breast cancer cell lines viability. The porous structures are nontoxic to cancer cells. Cell viability reduction was only observed after the release of SA from MCM- 41 followed by SBA-15 in both breast cancer cell lines., F.M.S. and N.V. are recipients of PhD fellowships (SFRH/BD/ 87139/2012 and SFRH/BD/97797/2013) from Fundação para a Ciência e a Tecnologia (FCT, Portugal). M.S. also acknowledges FCT for a postdoc grant(SFRH/BPD/65978/2009).The authors thank the FCT and FEDER-COMPETE-QREN-EU for financial support to the Research Centers, CQ/UM, PEst-C/ QUI/UI0686/2013 (F-COMP-01-0124-FEDER-037302), project EXPL/QEQ-QFI/2078/2013 (F-COMP-01-0124-FEDER041966), Life and Health Sciences Research Institute (ICVS, University of Minho, Portugal), CICECO, PEst-C/CTM/LA0011/2013 (F-COMP-01-0124-FEDER-037271)andLSRE/ LCM, PEst-C/EQB/LA0020/2013. The NMR spectrometer is part of the National NMR Network (RNRMN), supported with funds from FCT/QREN.

The effect of the molecular structure of monosaccharides on their electrochemical behavior at a gold electrode in alkaline medium was investigated in order to elucidate the relation between the structure and electro-reactivity. The oxidation of the aldehyde hydrate (or hemiacetal) at C1 carbon atom is the easiest occurring at E

The electrocatalytic oxidation of d -galactose was investigated on platinum, gold and nickel electrodes in 0.1 M NaOH medium. The oxidation of galactose on nickel takes place in the NiOOH region and leads to the cleavage of the C–C bonds. This was confirmed by HPLC analyses of electrolyzed solutions which demonstrate relatively high amounts of low molar mass carboxylic acids, i.e., formic and glycolic acids. The oxidation of galactose on platinum is initiated at very low potentials, i.e., −0.8 V vs. SCE probably without oxygenated species on the electrode surface and gives moderate selectivity towards galactonic acid. The important effect of the lead adatoms on the electrocatalytic properties of platinum was demonstrated by the increase in the yield of galactonic acid from 34% to 67% with addition of 10 −5 M Pb 2+ . On gold, galactose oxidation begins at approximately −0.5 V vs. SCE and is probably catalysed by the presence of hydrous gold oxides. The best yield of galactonic acid, 86%, was obtained after 6 h of electrolysis using a two potential program: −0.1 V vs. SCE for 30 s, 1.5 V for 1 s.

The electrocatalytic oxidation of d -xylose was performed in alkaline medium at both platinum and gold electrodes. The higher catalytic activity of gold was clearly demonstrated. Cyclic voltammetric studies were performed in a wide range of sweep rates (0.010–1.00 V s −1 ), various concentrations of d -xylose and of hydroxide. The influence of temperature was also studied. Kinetic data was obtained. The chromatographic analysis has identified xylonic acid (0.5 to 5×10 −3 mol dm −3 ) as the main oxidation product produced during the electrolysis of d -xylose, on Pt and Au electrodes, respectively, at potentials corresponding to the main oxidation peaks. The d -xylose conversion yield was found to be higher on Au than on Pt (98% against 26%). Other carboxylic acids, in concentrations lower than 10 −3 mol dm −3 , were identified by high-performance liquid chromatography (HPLC), as secondary products, namely glyceric; glycolic and formic acids, during the electrolysis on both electrode materials. On the other hand, tartaric (4.6%) and glyoxilic acids (14.0%) have been identified during the electrolysis on Au and Pt electrodes, respectively. Traces of tartronic and of oxalic acids have also been identified. HPLC studies have demonstrated the higher selectivity of Au electrodes for the production of xylonic acid.

The preparation of chiral metal complexes in NaY zeolite is reported. The guests, chiral metal complexes, were entrapped in the supercages of NaY zeolite (host) by a two-step process in the liquid phase: (i) inclusion of the selected transition metal (rhodium(III) and manganese(II)) by ion-exchange in the porous structure and (ii) introduction of the chiral ligand, an D-erythrose amino derivative, namely (2R,4S,5R)-4-[(N-methylamino)methyl]-2-phenyl-1,3-dioxan-5-ol, followed by assembly of the complex inside the void space of the zeolite. Structural (FTIR and XRD), surface studies (SEM) and chemical analyses were used to characterize the new host guest catalysts and the results indicated that chiral metal complexes were successfully encapsulated in supercages of the NaY zeolite. Catalytic studies were performed in liquid phase for norbornene oxidation using tert-butyl hydroperoxide as the oxygen source. The catalytic results were compared with styrene and cyclohexanol oxidation as model reactions. The prepared chiral catalysts exhibited catalytic activity for all oxidation reactions. The stability of the catalysts before and after reaction was confirmed by cyclic voltammetry and FTIR studies., The authors thank Dr. M. F. R. Pereira for support in the TGA analysis. I.K.B., A.R.S., and C.O. thank the Foundation for the Science and Technology (FCT, Portugal), for the contract under "Programa Ciencia 2007 e 2008". A.R.S. also thanks FCT for the contract under "Investigador FCT 2012" and I.K.B. also is thankful for the contract under the project NORTE-07-0124-FEDER-000039. The authors thank the FCT and FEDER-COMPETE-QREN-EU for financial support to the Research Centers, CQ/UM, PEst-C/QUI/UI0686/2013 (F-COMP-01-0124-FEDER-037302), the project NORTE-07-0124-FEDER-000039, the NMR Portuguese network (PTNMR, Bruker Avance III 400-University Minho), and CICECO/UA (Pest-C/CTM/LA0011/2013)., info:eu-repo/semantics/publishedVersion

Lactic acid bacteria (LAB) are a promising solution to reduce exposure to dietary mycotoxins because of the unique mycotoxin decontaminating characteristic of some LAB. Ochratoxin A (OTA) is one of the most prominent mycotoxins found in agricultural commodities. The present work reports on the ability of Pediococcus parvulus strains that were isolated from Douro wines that spontaneously underwent malolactic fermentation to detoxify OTA. These strains were identified and characterised using a polyphasic approach that employed both phenotypic and genotypic methods. When cultivated on OTA-supplemented MRS media, OTA was biodegraded into OTα by certain P. parvulus strains. The presence of OTα was confirmed using LC-MS/MS. The conversion of OTA into OTα indicates that the OTA amide bond was hydrolysed by a putative peptidase. The rate of OTA biodegradation was found to be dependent on the inoculum size and on the incubation temperature. Adsorption assays with dead P. parvulus cells showed that approximately 1.3% ± 1.0 of the OTA was adsorbed onto cells wall, which excludes this mechanism in the elimination of OTA by strains that degrades OTA. Under optimum conditions, 50% and 90% of OTA was degraded in 6 and 19 h, respectively. Other LAB strains that belonged to different species were tested but did not degrade OTA. OTA biodegradation by P. parvulus UTAD 473 was observed in grape must. Because some P. parvulus strains have relevant probiotic properties, the strains that were identified could be particularly relevant to food and feed applications to counteract the toxic effects of OTA., This work was funded by FEDER funds through the "Programa Operacional Factores de Competitividade - COMPETE" and by national funds through "Fundacao para a Ciencia e a Tecnologia - FCT", Ref. FCOMP-01-0124-FEDER-028029 and PTDC/AGR-TEC/3900/2012, respectively. The authors also thank the FCT Strategic Project PEst-OE/EQB/LA0023/2013 and the Project "BioInd - Biotechnology and Bioengineering for improved Industrial and Agro-Food processes, REF. NORTE-07-0124-FEDER-000028" co-funded by the Programa Operacional Regional do Norte (ON.2 - O Novo Norte), QREN, FEDER. Luis Abrunhosa was supported by the grant SFRH/BPD/43922/2008 from FCT.

The present work aims to evaluate the bacterial composition and activity (carbon and nitrogen removal) of nitrifying biofilms exposed to 50 μg L−1 of tetracycline. The tetracycline removal efficiency and the occurrence of tetracycline resistance (tet) genes were also studied. Two sequencing batch biofilm reactors (SBBRs) fed with synthetic wastewater were operated without (SBBR1) and with (SBBR2) the antibiotic. Both SBBRs showed similar organic matter biodegradation and nitrification activity. Tetracycline removal was about 28% and biodegradation was probably the principal removal mechanism of the antibiotic. Polymerase chain reaction-denaturing gradient gel electrophoresis analysis of the bacterial community showed shifts leading to not only the fading of some ribotypes, but also the emergence of new ones in the biofilm with tetracycline. The study of the tet genes showed that tet(S) was only detected in the biofilm with tetracycline, suggesting a relationship between its occurrence and the presence of the antibiotic., The work described in this paper was financially supported by FCT - Foundation for Science and Technology (Portugal) - by the PhD student grant SFRH/BD/44596/2008.

The present work assessed the impact of an external electron acceptor on phosphorus fluxes between water-sediment interface. Microcosm experiments simulating a sediment microbial fuel cell (SMFC) were carried out and phosphorus was extracted by an optimized combination of three methods. Despite the low voltage recorded, ∼96 mV (SMFC with carbon paper anode) and ∼146 mV (SMFC with stainless steel scourer anode), corresponding to a power density of 1.15 mW/m2 and 0.13 mW/m2, it was enough to produce an increase in the amounts of metal bound phosphorus (14% vs 11%), Ca-bound phosphorus (26% vs 23%) and refractory phosphorus (33% vs 28%). These results indicate an important role of electroactive bacteria in the phosphorus cycling and open a new perspective for preventing metal bound phosphorus dissolution from sediments., The authors are indebted and grateful to the Regional Department of Water Resources and Land Planning (Azores) and its staff. The authors also acknowledge the Grant SFRH/BPD/8052812011 from the Foundation for Science and Technology, Portugal, awarded to Gilberto Martins.

The analysis of sucronic acids produced by the electrocatalytic oxidation of sucrose is described. The main reaction products, l′-monocarboxylic and 6-monocarboxylic acids of sucrose, were identified by means of gas and liquid chromatography, mass spectrometry, NMR and i.r. spectroscopy, and acid hydrolysis. The quantitative analysis of reaction products other than the sucronic acids was realized by ionic chromatography (Dionex), whereas that of the sucronic acids was carried out using their acid hydrolysis products.

In this study we propose a suitable method for the solar-activated controlled release of volatile compounds from polymeric microcapsules bonded with photocatalytic nanoparticles. These reservoirs can find applications, for example, in the controlled release of insecticides, repellents, or fragrances, amongst other substances. The surfaces of the microcapsules have been functionalized with TiO2 nanoparticles.Upon ultraviolet irradiation, redox mechanisms are initiated on the semiconductor surface resulting in the dissociation of the polymer chains of the capsule wall and, finally, volatilization of the encapsulated compounds. The quantification of the output release has been performed by gas chromatography analysis coupled with mass spectroscopy., Strategic Project PEST-C/FIS/UI607/2011 and PTDC/CTMNAN/119979/2010 Project

The studies of potentiation of 5-fluorouracil (5-FU), a traditional drug used in the treatment of several cancers, including colorectal (CRC), were carried out with zeolites Faujasite in the sodium form, with different particle sizes (NaY, 700nm and nanoNaY, 150nm) and Linde type L in the potassium form (LTL) with a particle size of 80nm. 5-FU was loaded into zeolites by liquid-phase adsorption. Characterization by spectroscopic techniques (FTIR, 1H NMR and 13C and 27Al solid-state MAS NMR), chemical analysis, thermal analysis (TGA), nitrogen adsorption isotherms and scanning electron microscopy (SEM), demonstrated the successful loading of 5-FU into the zeolite hosts. In vitro drug release studies (PBS buffer pH 7.4, 37°C) revealed the release of 80-90% of 5-FU in the first 10min. To ascertain the drug release kinetics, the release profiles were fitted to zero-order, first-order, Higuchi, Hixson-Crowell, Korsmeyer-Peppas and Weibull kinetic models. The in vitro dissolution from the drug delivery systems (DDS) was explained by the Weibull model. The DDS efficacy was evaluated using two human colorectal carcinoma cell lines, HCT-15 and RKO. Unloaded zeolites presented no toxicity to both cancer cells, while all DDS allowed an important potentiation of the 5-FU effect on the cell viability. Immunofluorescence studies provided evidence for zeolite-cell internalization., RA is recipient of fellowship SFRH/BI/51118/2010 from Fundacao para a Ciencia e a Tecnologia (FCT, Portugal). This work was supported by the FCT projects refs. PEst-C/QUI/UI0686/2011 and PEst-C/CTM/LA0011/2011 and the Centre of Chemistry and Life and Health Sciences Research Institute (University of Minho, Portugal). The NMR spectrometer is part of the National NMR Network (RNRMN), supported with funds from FCT/QREN (Quadro de Referencia Estrategico Nacional).

The biological oxygen demand (BOD) may be the most used test to assess the amount of pollutant organic matter in water; however, it is time and labor consuming, and is done ex-situ. A BOD biosensor based on the microbial fuel cell principle was tested for online and in situ monitoring of biodegradable organic content of domestic wastewater. A stable current density of 282±23 mA/m2 was obtained with domestic wastewater containing a BOD5 of 317±15 mg O2/L at 22±2 °C, 1.53±0.04 mS/cm and pH 6.9±0.1. The current density showed a linear relationship with BOD5 concentration ranging from 17±0.5 mg O2/L to 78±7.6 mg O2/L. The current generation from the BOD biosensor was dependent on the measurement conditions such as temperature, conductivity, and pH. Thus, a correction factor should be applied to measurements done under different environmental conditions from the ones used in the calibration. These results provide useful information for the development of a biosensor for real-time in situ monitoring of wastewater quality., Fundação para a Ciência e a Tecnologia (FCT)

The electrocatalytic oxidation of saccharose solutions was carried out in alkaline medium on various noble and non-noble electrodes, with the aim of checking the electroreactivity of saccharose and its potentiality as a raw material for electrosynthesis. The best electrocatalytic activity was obtained with gold. In this latter case, chromatographic analysis of electrolysed solutions allowed us to identify numerous monocarboxylic acids, some of them resulting from the breaking of the COC bond.

Long term electrolyses of aqueous solutions of D-gluconic acid, in alkaline medium, were carried out on smooth and upd Pb modified Pt electrodes. The reaction products in solution were analysed by ionic chromatography. It was found that the kinetics of oxidation and the orientation of the reaction depend strongly on the catalytic properties of the surface. On a smooth Pt electrode, the main products of D-gluconic acid oxidation are oxalic, tartaric, 5-keto-D-gluconic and D-glucuronic acids, while on Pt-Pb electrodes, D-gluconic acid is oxidized selectively to 2-keto-D-gluconic acid. This product and other by-products were identified by GC-MS coupling techniques.

An easy preparation of 4-amino-1H-pyrrole-3-carbonitrile derivatives and their transformation into new substituted pyrrolo[3,2-b]pyridines is described. The one-step transformation was carried out via Friedlander reaction under microwave irradiation and by classical heating methods. The use of microwave irradiation led to high conversion and shorter reaction times.

An easy preparation of 4-aminopyrrole-3-carbonitrile derivatives, and their transformation into new substituted pyrrolo[3,2-b]pyridines is described, in one step, via Friedländer reaction under microwave irradiation and classical heating methods. The use of microwave irradiation led to high conversion and shorter times., Fundação para a Ciência e a Tecnologia (FCT) - NMR Network, REEQ/ 630/QUI/2005, SFRH/BPD/31490/2006, Fundo Europeu de Desenvolvimento Regional (FEDER)

The goal of this study is the preparation of new heterogeneous catalytic materials to be used in oxidation reactions under mild conditions through the valuation of heavy metals in wastewater. The samples used in the immobilization of chromium complexes were prepared from a dichromate solution of 100 mgCr L−1. The zeolite CrNaY was prepared from a robust biosorption system consisting of a bacterial biofilm, Arthrobacter viscosus, supported on zeolite NaY. The biofilm performs the reduction of Cr(VI) to Cr(III) and this cation is retained in the zeolite by ion exchange. The immobilization of chromium complexes with heterocyclic ligands in the supercages of Y zeolite was performed by the in situ synthesis with three different ligands, 3-methoxy-6-chloropyridazine (A), 3-piperidino-6-chloropyridazine (B) and 1-(2-pyridylazo)-2-naphthol (C). A sample loaded with Cr from a liquid solution with the same initial concentration was prepared as a reference through the traditional direct ion-exchange method and coordinated with ligand (A). The resulting catalysts were fully characterized by different techniques (FTIR, XRD, TGA, SEM, Raman, cyclic voltammetric studies and chemical analysis) and the results confirmed that the Cr complexes were immobilized in supercages of NaY. Catalytic studies were performed in liquid phase for the cyclohexene oxidation, at 40 °C, using tert-butyl hydroperoxide (TBHP) as the oxidizing agent. All the prepared catalysts exhibited catalytic activity for the oxidation reaction., União Europeia. Fundo Europeu de Desenvolvimento Regional (FEDER), Fundação para a Ciência e a Tecnologia (FCT) - ref. POCTI/44449/CTA/2002, POCTI-SFA-3-686

This work reports on the application of solar-activated photocatalytic thin films that allow the controlled-release of volatile agents (e.g., insecticides, repellents) from the interior of adsorbed polymeric microcapsules. In order to standardize the tests,a quantification of the inherent controlled-release of a particular volatile agent is determined by gas chromatography coupled to mass spectroscopy, so that an application can be offered to a wide range of supports from various industrial sectors, such as in textiles (clothing, curtains, mosquito nets). This technology takes advantage of the established photocatalytic property of titanium dioxide (TiO2) for the use as an active surface/site to promote the controlled-release of a specific vapor (volatile agentfrom within the aforementioned microcapsules., Portuguese FCT COMPETE scientific programs, with references NANO/NTec-CA/0046/2007 and PTDC/CTM-NAN/119979/2010

This work aims to investigate the electrocatalytic oxidation of sucrose on smooth and upd-lead modified platinum electrodes in order to find experimental conditions for selective electrosynthesis of high value added products. The preliminary results obtained show that the oxidation of sucrose on Pt-Pb electrodes leads mainly to C12 products, such as the 1′-monoacid and the 6-monoacid of sucrose.

In the title compound, C20H18N2O2S, the indole mean plane and benzene ring form a dihedral angle of 65.0 (1)°. In the crystal structure, weak intermolecular N—H...π and C—H...O interactions link the molecules into ribbons propagated along [100].

The preparation of the (N,N'-diarylacetamidine)rhodium(III) complex in the cavities of zeolite Y is reported. The guest rhodium(III) complex was entrapped in the supercages of zeolite Y as a host by a two-step process in the liquid phase: (I) inclusion of rhodium(III) by ion-exchange in the structure and (II) introduction of N,N'-diarylacetamidine ligand followed by assembly of the complex inside the void space of the zeolite. The neat complex has also been prepared and characterized. The appropriate process selected for the in situ complex synthesis involved using an N,N'-diarylacetamidine ligand : rhodium(III) molar ratio of 4 : 1. Spectroscopic studies (Fourier transform infrared spectroscopy), chemical analyses, surface (X-ray photoelectron spectroscopy, scanning electron microscopy and X-ray diffraction) and cyclic voltammetric studies were used to characterize the new host-guest materials. Analysis of the data of the neat and encapsulated complex show that the coordination of the rhodium(III) ion (as a guest in the host structure) by the nitrogen atoms of the N,N'-diarylacetamidine ligand occurred in a 2 : 1 stoichiometry.

CoPAN complex has been entrapped in the supercages of Y zeolite and the redox properties of this zeolite-encapsulated complex were investigated by cyclic voltammetry with a new method for the preparation of carbon toray-zeolite-modified electrode. Formation of the CoPAN complex was ascertained by surface analysis (SEM, XRD), chemical analysis (CA), spectroscopy methods (FTIR and UV/vis) and cyclic voltammetry in aqueous medium with zeolite-modified electrodes. The cyclic voltammetry studies obtained with a zeolite-modified electrode shows evidence for electroactivity restricted to boundary associated CoPAN complex.