Browsing by Author "Oliveira, C."
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- Aroma precursors of grapes: contribution of variety and vineyard traning system to port wine aromaPublication . Sousa, L.; Moreira, N.; Queiroz, J.; Oliveira, M.B.; Santos, C.; Oliveira, C.; Ferreira, A. C. Silva; Pinho, P. Guedes deIn order to evaluate the influence of the vine training system in the composition in terpenes, norisoprenoids and their precursors (carotenoids and glycosidic molecules), these compounds were quantified in grapes and Port wines belonging to two varieties: Touriga Nacional and Touriga Franca from Douro Region. The double cordon LYS 2/3 system was compared with the traditional method, the vertical shoot positioning VSP system. Touriga Nacional grapes and wines have higher contents in carotenoids, free and glycosylated fractions of terpenic and norisoprenoids compounds than Touriga Franca. In general, LYS 2/3 training system produced grapes and wines with high content in glycosylated fractions of terpenes and nor-isoprenoids, being more appropriate to the production of Port wines, which are submitted to an aging process.
- Aroma precursors of grapes: contribution of variety and vineyard traning system to port wine aromaPublication . Sousa, L.; Moreira, N.; Queiroz, J.; Oliveira, M. B.; Santos, C.; Oliveira, C.; Ferreira, A. C. Silva; Pinho, P. Guedes de
- Carotenoid compounds found in grapes and their relationship to plant water statusPublication . Oliveira, C.; Ferreira, A. C. Silva; Pinto, M. M. Mendes; Hogg, T.; Alves, F.; Pinho, P. Guedes de
- Carotenoid compounds in grapes and their relationship to plant water statusPublication . Oliveira, C.; Ferreira, A. C. Silva; Pinto, M. Mendes; Hogg, T.; Alves, F.; Pinho, Guedes deThe aim of this work was to study the relationship between carotenoid contents in grapevine berries and plant water status. For this purpose, a black grapevine variety, Vitis vinifera L. cv. Touriga Nacional, was studied. The experiments were carried out in the same Douro vineyards, with plants of the same age, in two different water retention soils. A higher water retention capacity soil, soil A, and a lower water retention capacity soil, soil B, were both in a 1.2 m deep silt-loam schist-derived soil. The training system was the double cordon trained and spur pruned. A first range was nonirrigated (NI) and a second one was irrigated (I), 60% of evapotranspiration (ET0). For soil B, a 30% of ET0 treatment was also applied. The plant water status was estimated by predawn leaf water potential. The effects of plant water status on berry growth were studied by measurement of the berry weight and total soluble solids (°Brix). The carotenoid profile was quantitatively determined by high-performance liquid chromatography/diode array. Carotenoids determined were â-carotene, lutein, neoxanthin, violaxanthin, and luteoxanthin. The comparison between irrigated and nonirrigated grapes was followed from 2 weeks before veraison until the ripe stage. Results showed that at harvest time, berries exposed to the NI had a lower weight than those exposed to the irrigated treatment (60% of ET0), 0.89 vs 1.36 g/berry and 0.94 vs 1.34 g/berry, for soils A and B, respectively. The irrigated treatment contributed to a higher sugar concentration in both soils. However, depending on the soil water retention capacity, the carotenoid contents were different in soils A and B. For soil A, the total carotenoid content was similar for both NI and I treatments. However, with regard to soil B, in irrigated treatment, levels of carotenoids were approximately 60% lower than those found for the NI. It seems to be possible to produce higher weight berries (with higher sugar levels) with similar carotenoid contents. On the other hand, soil characteristics had a larger influence than irrigation on the concentration of carotenoids in grapes, resulting in an important viticultural parameter to take into account in aroma precursor formation.
- Mushroom-derived polysaccharides as bioactive agents for skin regeneration: evaluation of antimicrobial, wound-healing, and immunomodulatory effectsPublication . Fernandes, A.; Lopes, A.; Magalhães, R.; Oliveira, C.; Pintado, M.; Tavaria, F.Mushroom polysaccharides have emerged as promising bioactive agents for enhancing skin regeneration. This study evaluates three polysaccharide-rich fractions (SB, SC, RD) obtained by hot water and alkaline extractions from Coriolus versicolor, Pleurotus ostreatus, and Hericium erinaceus. Their potential to promote skin repair was investigated by analyzing effects on cell proliferation and migration, immune modulation, and microbial growth inhibition. These fractions were previously characterized by several chemical and structural characterization methods that revealed significant presence of bioactive molecules (e.g., glucans, proteins, phenolics). Cell viability was accessed by PrestoBlue and MTT assays in HaCat and L929 cell lines, revealing the non-toxicity of the compounds at tested concentrations. Furthermore, proliferation assays (BrdU incorporation) and migration assays (scratch assay) in HaCaT cells were conducted at optimized concentrations (0.6 and 0.3 mg/mL). Notably, C. versicolor fractions promoted wound closure of the injured monolayer by 95% after 48 h (at 0.6 mg/mL) compared to 66% in the non-treated control. The fractions exhibited broadspectrum antimicrobial and antibiofilm activity in Gram-positive bacteria (S. epidermidis, MRSA), Gram-negative bacteria (P. aeruginosa, E. coli) and yeast (C. albicans, C. tropicalis). Microbial growth inhibition varied across the three species and extraction method, ranging from 30% to 70% at a concentration of 20 mg/mL. Additionally, immunomodulatory effects are being assessed by measuring key pro-inflammatory cytokines (TNF-?, IL-17A, IL-1?, IL-6) and anti-inflammatory (IL-10) to elucidate how these polysaccharides regulate inflammation during healing and skin repair. These findings highlight the potential of polysaccharides as multifunctional agents in dermatological applications, supporting their role in developing innovative, natural-based therapies for skin regeneration.
- Oxidation Management of White WinesPublication . Ferreira, A. C. Silva; Rodrigues, A.; Bento, F.; Geraldo, D.; Silva, A.; Martins, R.; Lopes, V.; Oliveira, C.; Pinho, P. Guedes
- Oxidation Management of White WinesPublication . Ferreira, A. C. Silva; Rodrigues, A.; Bento, F.; Geraldo, D.; Silva, A.; Martins, R.; Lopes, V.; Oliveira, C.; Pinho, P. Guedes
- Oxidation Management of White Wines Using Cyclic Voltammetry and Multivariate Process MonitoringPublication . Martins, R.; Bento, F.; Geraldo, D.; Lopes, V.; Lopes, T. I. M. S.; Oliveira, C.; Ferreira, A. C. Silva
- Simultaneous determination of ketoacid and dicarbonyl compounds key maillard intermediates on the generation of aged wine aromaPublication . Ferreira, A. C. Silva; Reis, S. F.; Oliveira, C.; Pinho, P. Guedes de