Dibromomethane (DBM) and 1,2-dibromoethane (DBA) are two brominated volatile contaminants used in several industrial applications which are often detected in groundwater. The electrochemical degradation of DBM and DBA was studied at different cathode potentials in aqueous solution using an inexpensive graphite fiber brush electrode. The degradation followed first-order kinetics with respect to the nominal concentration of the brominated compounds, and the kinetic constant increased concomitantly with the decrease of the cathode potential. During the electrochemical dehalogenation 96.8% and 99.8% of the bromide in DBM and DBA was released as bromine ions, respectively. The main non-brominated compounds detected during the degradation of DBM and DBA were methane and ethene, respectively. In addition, traces of formic acid for DBM and acetic acid for DBA degradation were detected. The non-toxicity of the effluent was confirmed by a Microtox test. The efficient electrochemical degradation of DBM and DBA and the lack of toxic products open the door for a simple and non-toxic electrochemical approach for removing aliphatic brominated compounds from aquifers and other water sources.

Mycobacterium abscessus is a reemerging pathogen that causes pulmonary diseases similar to tuberculosis, which is caused by Mycobacterium tuberculosis. When grown in agar medium, M. abscessus strains generate rough (R) or smooth colonies (S). R morphotypes are more virulent than S morphotypes. Cording has also been related to the virulence of M. tuberculosis. In this species, the presence of mycolic acids and surface-exposed cell wall lipids has been correlated with the formation of cords. The objective of this work was to study the roles of the surface-exposed cell wall lipids and mycolic acids in the formation of cords in M. abscessus. A comparative study of the pattern and structure of mycolic acids was performed on R (cording) and S (non-cording) morphotypes derived from the same parent strains with the aid of NMR spectroscopy.

The fungus Pleurotus ostreatus was investigated to assess its ability to remove diclofenac, ketoprofen and atenolol spiked at 10 mg/L each one in hospital wastewater. The degradation test was carried out in a fluidized bed bioreactor testing both the batch and the continuous mode. In batch mode, diclofenac disappeared in less than 24 h, ketoprofen was degraded up to almost 50% in 5 d while atenolol was not removed. In continuous mode, diclofenac and ketoprofen removals were about 100% and 70% respectively; atenolol degradation was negligible during the first 20 d but it increased up to 60% after a peak of laccase production and notable biomass growth. Two intermediates of diclofenac and ketoprofen were detected by NMR spectroscopy. Moreover P. ostreatus was able to reduce chemical oxygen demand of the hospital wastewater which is an important advantage comparing to other fungi in order to develop a wastewater treatment process.

The ability of chloroperoxidase (CPO) to catalyze amino alcohol oxidations was investigated. The oxidations of compounds with different configurations with respect to the amine position towards hydroxyl – using H2O2 and tert-butyl hydroperoxide (t-BuOOH) – were analyzed in terms of the initial reaction rate, substrate conversion, and CPO operational stability. It was observed that the further the amino group from the hydroxyl, the lower the initial reaction rate. The effect of the amino-protecting group and other substituents (i.e., methyl and hydroxyl) was also examined, revealing an increase in steric hindrance due to the effect of bulky substituents. The observed reaction rates were higher with t-BuOOH, whereas CPO was more stable with H2O2. Final products and intermediates were analyzed directly from the crude by NMR spectroscopy.

The rough morphotypes of non-tuberculous mycobacteria have been associated with the most severe illnesses in humans. This idea is consistent with the fact that Mycobacterium tuberculosis presents a stable rough morphotype. Unlike smooth morphotypes, the bacilli of rough morphotypes grow close together, leaving no spaces among them and forming large aggregates (clumps). Currently, the initial interaction of macrophages with clumps remains unclear. Thus, we infected J774 macrophages with bacterial suspensions of rough morphotypes of Mycobacterium abscessus containing clumps and suspensions of smooth morphotypes, primarily containing isolated bacilli. Using confocal laser scanning microscopy and electron microscopy, we observed clumps of at least 5 rough-morphotype bacilli inside the phagocytic vesicles of macrophages at 3 hours post-infection. These clumps grew within the phagocytic vesicles, killing 100% of the macrophages at 72 hours post-infection, whereas the proliferation of macrophages infected with smooth morphotypes remained unaltered at 96 hours post-infection. Thus, macrophages phagocytose large clumps, exceeding the bactericidal capacities of these cells. Furthermore, proinflammatory cytokines and granuloma-like structures were only produced by macrophages infected with rough morphotypes. Thus, the present study provides a foundation for further studies that consider mycobacterial clumps as virulence factors.

Mycobacterium tuberculosis and Mycobacterium bovis are the principal agents responsible for human tuberculosis and tuberculosis in domestic and wild animals. Both form microscopic cords, a phenotypic characteristic that has been related to their virulence. The compounds responsible for cording are unknown, but a recent work has shown that cording could be related to the fine structure of α-mycolic acids. This investigation attributes the need of a proximal cyclopropane in α-mycolic acids for cording in Mycobacterium tuberculosis and Mycobacterium bovis BCG and proposes cyclopropanases as good targets for new chemotherapeutic agents. As in addition to M. tuberculosis and M. bovis, other Mycobacterium species form microscopic cords, it would be of great interest to know if the relationship between proximal cyclopropanation of α-mycolic acids and cording could be extended to non-tuberculous mycobacteria. In this work we have studied the correlation between cording and cyclopropanation of α-mycolic acids by Nuclear Magnetic resonance (NMR) spectroscopy and Scanning Electron Microscopy (SEM) images.

The phenolic fraction of a monovarietal extra virgin olive oil (EVOO) from Olea europaea L. var. Cornezuelo was studied by the hyphenated HPLC-DAD-SPE-NMR/MS techniques. This survey led to the identification of 25 main compounds. One was identified as a new diastereoisomer of the aldehydic form of oleuropein aglycone (AOA) and characterized by 1D and 2D NMR techniques. The relative configuration of this new AOA was determined as 5R*,8S*,9S* on the basis of the results obtained from the combination of NOE experiments and Monte Carlo conformational search calculations. Assuming, as for the described diastereoisomers, that the new AOA comes from the natural oleuropein aglycone (OA), the absolute configuration was proposed as 5S,8R,9R.

The white-rot fungus Trametes vesicolor degraded naproxen (10 mg L−1) in a liquid medium to non-detectable levels after 6 h. When naproxen was added in the range of concentrations typically found in the environment (55 μg L−1), it was almost completely degraded (95%) after 5 h. In vitro degradation experiments with purified laccase and purified laccase plus mediator 1-hydroxybenzotriazol showed slight and almost complete naproxen degradation, respectively. A noticeable inhibition on naproxen degradation was also observed when the cytochrome P450 inhibitor 1-aminobenzotriazole was added to the fungal cultures. These data suggest that both enzymatic systems could play a role in naproxen degradation. 2-(6-hydroxynaphthalen-2-yl)propanoic acid and 1-(6-methoxynaphthalen-2-yl)ethanone were structurally elucidated by HPLC-DAD-MS and NMR as degradation intermediates of naproxen. After 6 h of incubation, both parent compound and intermediates disappeared from the medium. The non-toxicity of the treated medium was confirmed by Microtox test.