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The use of wood species from Brazilian forests has not been the subject of studies on oenology. Thus, the main goal of this study was to carry out a comparative analysis of the impact of several different Brazilian wood species (Jequitibá, Jaqueira, Ipê, Amburana, and Grápia) on global phenolic parameters, chromatic characteristics, and sensory profile of one red and white wines during a short wood contact time. In addition, toasted European oak wood (Q. petraea) was also used. Regarding the specific impact of the use of the different wood species studied, red wines stored in contact during 15 and 30 storage days with Amburana, Grápia, and Ipê wood cubes showed the highest total phenolic content, while for white wines, the highest total phenolic values were detected for the wines stored in contact with Jequitibá, Jaquera, and Amburana wood cubes after 15 storage days. Regarding the sensorial quality, after 30 storage days, red wines stored in contact with Amburana and Jaquera woods obtained the highest global appreciation scores. For white wines, the highest global appreciation scores were obtained for the wines stored in contact with Ipê and Amburana wood cubes for 15 days.

The preservation of the old vine heritage, combined with the fact that old vines could present greater resistance to biotic and abiotic factors, has led to an increase in research studies about the contribution of vine age on grape and wine quality. Thus, the main goal of this work was to evaluate the potential influence of grapevine age on several general physicochemical and phenolic parameters during grape maturation of a Rabigato white grape variety. Therefore, grapes from two adjacent vineyards, with an age difference of 30 years (one with 20 years and the other with 50 years, at the beginning of this study) were studied. At technological maturation, the results obtained for the three consecutive vintages studied (2019 to 2021), and for the general physicochemical parameters analysed, do not seem to indicate a clear differentiation between the grape musts obtained from the younger and the older vineyards. However, for grape phenolics, the results suggest that vine age could be a potential factor on phenolic content, nevertheless not totally confirmed by the results at technological maturation during the three consecutive vintages considered. With this work we will contribute to expand the knowledge about the potential impact of the vine age on grape composition.

In the last years, there has been an increase in consumption of wine vinegars in Portugal. Thus, the aim of this work was to evaluate the phenolic composition and total antioxidant capacity from several commercial red wine vinegars commercialized in Portuguese market. Several parameters were evaluated: general phenolic composition, chromatic characteristics, individual anthocyanins and phenolic acids by HPLC, and total antioxidant capacity by two methodologies (DPPH and ABTS). For the different parameters analyzed, the red wine vinegars samples studied differed significantly. Vinegars with higher phenolic content tend to have lower lightness, but higher values of the red component color. High diversity of anthocyanins was detected, with some of the vinegars being distinguished by having significantly higher values of anthocyanins compared to the others, as was detected for the generality of the other phenolic parameters. The total antioxidant capacity was positively correlated with the different phenolic parameters. Finally, higher total antioxidant capacity was detected for the phenolic fraction containing anthocyanins and polymeric proanthocyanidins. The results obtained confirm that red wine vinegars are good sources of phenolic compounds and antioxidants. However, there is a great diversity of values for the various red wine vinegars commercialized in the Portuguese market.

The aim of present work was to investigate the impact of different oak (Q. alba, Q. robur and Q. pyrenaica), acacia and cherry wood chips on evolution of individual anthocyanin content, chromatic characteristics and antioxidant capacity by the use of model wine solutions. According to the results obtained, model wine solutions containing acacia and especially cherry wood extracts showed more evident changes of individual anthocyanin composition, especially due to the formation of large number of new direct condensation anthocyanins, than model wines with oak extracts. These results were accompanied also by a higher color degradation and a lower antioxidant potential of solutions containing the different wood chip extract species, compared with solutions containing only anthocyanin alone. This research contributes to a better knowledge about the color evolution of red wines when they are aging in contact with new alternative wood species, especially acacia and cherry.

The main object of the present study was to investigate the volatile composition and sensorial profile of vine leaves infusions prepared from vine leaves collected 30 and 60 days after grape harvest from two Portuguese red grape varieties (Touriga Nacional and Tinta Roriz). Twelve volatile compounds were detected in vine leaves infusions (6-methyl-5-hepten-2-one, 1-undecene, Z-citral, cedrenol, DL-limonene, 2,4-hexadien-2-ol, benzaldehyde, heptane-1,2,4,6-tetraene, cyclohexene 1-methyl-4-(1-methylethyl), 1,6-octadien-3-ol, 3,7-dimethyl, 5,9-undecadien-2-one-6,10-dimethyl-(5E) and α-cedrol). In addition, it was observed that the volatile compounds present in vine leaves infusions were dependent on the harvest time, with significantly major volatile content in vine leaves collected after 30 days of harvesting. Thus, it was more important the harvesting date for the volatile profile of vine leaves infusion than the vine leave grape cultivar. Similar tendency was also obtained for the sensory profile, with significant differences for astringency and aroma intensity attributes of vine leaves infusions according to the harvesting date.

The aim of present work was to investigate the phenolic and volatile composition of cherry, acacia, and oak (from different species) wood chips. By the use of HPLC-DAD 18 different phenolic compounds were detected and quantified while for volatile composition, 33 different compounds were detected by GC-MS. In general, wood samples from oak species showed the higher number of phenolic compounds detected, while cherry wood samples showed the lowest levels. In addition, some individual phenolic compounds were detected, specifically in some wood samples, such as robinetin in acacia woods and naringenin in cherry wood. For volatile composition, cherry wood chips samples showed the lowest volatile composition followed by increasing order by acacia, French, Portuguese and American wood chip samples. Oak wood chip samples from American species showed the highest volatile content, as a result of high levels of several specific compounds (furfural, 5-methyfurfural, β-methyl-γ-octalactones, guaiacol, vanillin and siringaldehyde).

The main objective of this work was to understand the effect of the addition of different commercial types of oenological tannins on red wine phenolic compounds and sensorial characteristics evolution. So, six different commercial oenological tannins obtained from different sources at an average dosage recommended by the manufactures were added to a red wine. During 120 wine aging days several phenolic parameters were analyzed (including several individual phenolic compounds by HPLC) and also the sensorial characteristics of the wines. Wines treated with oenological tannins showed higher total phenols and flavonoid phenols and lesser color degradation during the aging time considered. After 120 aging days, wines aged with oenological tannins showed more total and individual anthocyanins and significantly more red color that induced significantly color differences in relation to the untreated wine (especially for the wines treated with condensed tannins). From a sensorial point of view it was also possible to detect a clear differentiation between the wines.

Prediction and management of drug-induced renal injury (DIRI) rely on the knowledge of the mechanisms of drug insult and on the availability of appropriate animal models to explore it. Zebrafish ( Danio rerio) offers unique advantages for assessing DIRI because the larval pronephric kidney has a high homology with its human counterpart and it is fully mature at 3.5 days post-fertilization. Herein, we aimed to evaluate the usefulness of zebrafish larvae as a model of renal tubular toxicity through a comprehensive analysis of the renal alterations induced by the lethal concentrations for 10% of the larvae for gentamicin, paracetamol and tenofovir. We evaluated drug metabolic profile by mass spectrometry, renal function with the inulin clearance assay, the 3D morphology of the proximal convoluted tubule by two-photon microscopy and the ultrastructure of proximal convoluted tubule mitochondria by transmission electron microscopy. Paracetamol was metabolized by conjugation and oxidation with further detoxification with glutathione. Renal clearance was reduced with gentamicin and paracetamol. Proximal tubules were enlarged with paracetamol and tenofovir. All drugs induced mitochondrial alterations including dysmorphic shapes ('donuts', 'pancakes' and 'rods'), mitochondrial swelling, cristae disruption and/or loss of matrix granules. These results are in agreement with the tubular effects of gentamicin, paracetamol and tenofovir in man and demonstrate that zebrafish larvae might be a good model to assess functional and structural damage associated with DIRI. [ABSTRACT FROM AUTHOR]