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Amoxicillin (AMX) is one of the most commonly prescribed antibiotics around the world to treat and prevent several diseases in both human and veterinary medicine. Incomplete removal of AMX during wastewater treatment contributes to its presence in water bodies and drinking water. AMX is an emerging contaminant since its impact on the environment and human health remains uncertain. This contribution was aimed to evaluate the electrochemical oxidation (EO) of AMX using different anodes in tap water, NaCl or Na 2 SO 4 solutions and to evaluate the potential toxicity of remaining AMX and its by-products on zebrafish early-life stages. Chemical intermediates generated after EO were determined by mass spectrometry and their resulting antimicrobial activity was evaluated. AMX did not induce significant mortality in zebrafish during extended exposure but affected zebrafish development (increased body length) from 6.25 mg/L to 25 mg/L and inhibited enzymatic biomarkers. Carbon modified with titanium oxide (TiO 2 @C) anode achieved complete AMX removal in just a few minutes and efficiency of the supported electrolytes occurred in the following order: 0.1 M NaCl > 0.1 M Na 2 SO 4  > 0.01 M NaCl > tap water. The order of potential toxicity to zebrafish early life-stages related to lethal and sublethal effects was as follows: 0.1 M Na 2 SO 4 > 0.1 M NaCl >0.01 M NaCl = tap water. Additionally, the EO of AMX using TiO 2 @C electrode with 0.01 M NaCl was able to inhibit the antimicrobial activity of AMX, reducing the possibility of developing bacterial resistance., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this work, we have successfully synthesized a set of titania photocatalytic nanocomposites by the incorporation of different TiO 2 content on wheat bran residues. The obtained catalysts were characterized by different techniques including UV-Vis spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Transmission Electron Microscopy (TEM) while their photocatalytic activity was investigated in the oxidation of benzyl alcohol under UV light irradiation. Benzaldehyde yields were ca. 20%, with conversion in the systems of ca. 33% of benzyl alcohol by using 10%Ti-Bran catalyst, as compared to 33% yield to the target product (quantitative conversion of benzyl alcohol) using commercial pure TiO 2 (P-25). The photocatalytic activity results indicate that designed waste-derived nanomaterials with low TiO 2 content can efficiently photocatalyze the conversion of benzyl alcohol with relative high selectivity towards benzaldehyde., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Microcystin-leucine arginine (MC-LR) is the most abundant and toxic secondary metabolite produced by freshwater cyanobacteria. This toxin has a high potential hazard health due to potential interactions with liver, kidney and the nervous system. The aim of this work was the design of a simple and environmentally friendly electrochemical system based on highly efficient nanostructured electrodes for the removal of MC-LR in tap water. Titania nanoparticles were deposited on carbon (graphite) under a simple and efficient microwave assisted approach for the design of the electrode, further utilized in the electrochemical remediation assays. Parameters including the applied voltage, time of removal and pH (natural tap water or alkaline condition) were investigated in the process, with results pointing to a high removal efficiency for MC-LR (60% in tap water and 90% in alkaline media experiments, under optimized conditions)., Competing Interests: The authors declare no competing financial interests.

TiO₂ (anatase phase) has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO₂-magnetically-separable nanocomposites (MAGSNC) photocatalysts with different TiO₂ loading were synthesized using a simple one-pot mechanochemical method. Photocatalysts were characterized by a number of techniques and their photocatalytic activity was tested in the selective oxidation of benzyl alcohol to benzaldehyde. Extension of light absorption into the visible region was achieved upon titania incorporation. Results indicated that the photocatalytic activity increased with TiO₂ loading on the catalysts, with moderate conversion (20%) at high benzaldehyde selectivity (84%) achieved for 5% TiO₂-MAGSNC. These findings pointed out a potential strategy for the valorization of lignocellulosic-based biomass under visible light irradiation using designer photocatalytic nanomaterials.

Cu nanoparticles have been supported by two types of aluminosilicate materials with and without Zn in their composition in view of their application in the microwave-assisted conversion of glucose to valuable products via tandem formic acid-promoted dehydration (to 5-hydroxymethylfurfural--HMF) and further selective hydrogenation to 5-methylfurfuryl alcohol (MFA). Results show that interesting selectivities (up to 60% to MFA or HMF) could be achieved after short times of reaction (typically 2-30 min) using Cu-containing nanomaterials. Zn was found to play an interesting role in the selectivity to reduced products, even if present in very small quantities (0.2 wt%).