Alexandre Gonçalves

Goncalves, Alexandre; et al.
BACKGROUND Cropping practices focusing on agronomic water use efficiency and their impact on quality parameters must be investigated to overcome constraints affecting olive groves. We evaluated the response of olive trees (Olea europaea, cv. 'Cobrancosa') to different water regimes: full irrigation (FI, 100% crop evapotranspiration (ETc)), and three deficit irrigation strategies (DIS) (regulated (RDI, irrigated with 80% of crop evapotranspiration (ETc) in phases I and III of fruit growth and 10% of ETc in the pit hardening stage), and two continuous sustained strategies (SDI) - a conventional SDI (27.5% of ETc), and low-frequency irrigation adopted by the farmer (SDIAF, 21.2% of ETc). RESULTS The effects of water regimes on the plant water status, photosynthetic performance, metabolite fluctuations and fruit quality parameters were evaluated. All DIS treatments enhanced leaf tissue density; RDI and SDI generally did not affect leaf water status and maintained photosynthetic machinery working properly, and the SDIAF treatment impaired olive tree physiological indicators. The DIS treatments maintained the levels of primary metabolites in leaves, but SDIAF plants showed signs of oxidative stress. Moreover, DIS treatments led to changes in the secondary metabolism, both in leaves and in fruits, with increased total phenolic compounds, ortho-diphenols, and flavonoid concentration, and higher total antioxidant capacity, as well higher oil content. Phenolic profiles showed the relevance of an early harvest in order to obtain higher oleuropein levels with associated higher health benefits. CONCLUSION Adequate DIS are essential for sustainable olive growing, as they enhance the competitiveness of the sector in terms of olive production and associated quality parameters. (c) 2019 Society of Chemical Industry

Brito, Catia; Dinis, Lia-Tania; Luzio, Ana; Silva, Ermelinda; Goncalves, Alexandre; et al.
In a changing world, the search for new agronomic practices that help crops to maintain and/or increase yields and quality is a continuous challenge. We aim to evaluate kaolin (KL) and salicylic acid (SA) effectiveness as summer stress alleviating agents through physiological, biochemical and inununohistochemical analysis. Olive trees (Olea europaea L. cv. Cobrancosa) grown under rainfed conditions were sprayed with 5% KL and 100 mu M SA, at the beginning of summer, during two consecutive years. KL enhanced relative water content (RWC), stomatal conductance (g(s)) net photosynthesis (A) and leaf indole-3-acetic acid (IAA) signal, and decreased leaf sclerophylly, secondary metabolites and non-structural carbohydrates accumulation and abscisic acid (ABA). The trees treated with SA showed changes on IAA and ABA dynamics, and an enhancement in RWC, g(s), A, soluble proteins, and leaf P and Mg concentrations during the summer. Notably, KL and SA also allowed a faster restauration of the physiological functions during stress relief. In sum, KL and SA foliar sprays alleviated the negative effects induced by summer stress in olive trees performance, by modulation of distinct physiological and biochemical responses.

Nuno Mariz-Ponte; Sandra Martins; Alexandre Gonçalves; Carlos Correia; Carlos Ribeiro; Maria Celeste Dias; Conceição Santos
Solanum lycopersicum L. is among the healthiest fruits/vegetables due to its richness in bioactive compounds. However, its fruits from off-season (usually obtained in greenhouses that block UV-rays) have lower reputation than the ones of in-season/field productions. We hypothesise that moderate UV-A/UV-B irradiation during fruit development is able to improve its bioactive compounds and sensorial attributes, increasing its healthy properties. We supplemented for 30 days ‘MicroTom’ fruiting plants with two daily doses of UV-A (1 or 4 h) and UV-B (2 or 5 min). Irradiated plants showed higher ripening synchronization and produced more and smaller fruits. UV-A irradiation stimulated the fruit’s antioxidant capacity, and the antiradical activity by the accumulation of phenolic compounds including the flavonoids. Only the UV-A1 h condition promoted the accumulation of ortho-diphenols in tomato fruits. Regarding the consumers’ preference for aroma/taste, a consumers’ panel test ranked the tomatoes as UV-A 1 h, UVA 4 h, Control, UV-B 5 min and UV-B 2 min. We conclude that the supplementation of UV-A during pre-harvest is particularly effective in increasing ripening synchronization and fruit’s nutritional properties, potentially making these fruits more appealing to consumers.

Alexandre Gonçalves; Piebiep Goufo; Ana Barros; Raúl Domínguez-Perles; Henrique Trindade; Eduardo A S Rosa; Luis Ferreira; Miguel Rodrigues
The growing awareness of the relevance of food composition for human health has increased the interest of the inclusion of high proportions of fruits and vegetables in diets. To reach the objective of more balanced diets, an increased consumption of legumes, which constitutes a sustainable source of essential nutrients, particularly low-cost protein, is of special relevance. However, the consumption of legumes also entails some constraints that need to be addressed to avoid a deleterious impact on consumers' wellbeing and health. The value of legumes as a source of nutrients depends on a plethora of factors, including genetic characteristics, agro-climatic conditions, and postharvest management that modulate the dietary effect of edible seeds and vegetative material. Thus, more comprehensive information regarding composition, especially their nutritional and anti-nutritional compounds, digestibility, and alternative processing procedures is essential. These were the challenges to write this review, which focusses on the nutritional and anti-nutritional composition of Vigna unguiculata L. Walp, an emerging crop all over the world intended to provide a rational support for the development of valuable foods and feeds of increased commercial value.

Ederson Andrade; Alexandre Gonçalves; Ana Mendes-Ferreira; Valéria Silva; Victor Pinheiro; Miguel Rodrigues; Luis Ferreira
Background: Agro-industrial by-products are of low economic value as foods for human consumption but may have potential value as animal feedstuffs. This study evaluated a novel feedstuff, ensiled discarded apple (85%) and cowpea stover (15%) mixtures with two different ensiling periods (45 and 60 days), regarding the nutritive value, fermentation quality and aerobic stability.

Results: Generally, no differences (P > 0.05) were observed between ensiling periods for nutritive value and fermentation characteristics. Silages were stable after ensiling, presenting high lactic acid (77.3 g kg-1 dry matter (DM)) and acetic acid (54.7 g kg-1 DM) and low ethanol (15.7 g kg-1 DM) and NH3 -N (105.6 g kg-1 total N) concentrations. No butyric acid was detected in silages, and they were aerobically stable for up to 216 h. Lactic acid bacteria numbers were high at silo opening (7.14 log colony-forming units (CFU) g-1 ), while Enterobacteriaceae were not detected and yeasts/moulds were low (2.44 log CFU g-1 ). Yeast/mould and Enterobacteriaceae numbers grew considerably during 12 days of air exposure.

Conclusion: A mixture of low calibre discarded apples with cowpea stover can be used as animal feed after the ensiling process owing to its nutritive value and long aerobic stability. © 2017 Society of Chemical Industry.

Marinho, Catarina M.; Santos, Tiago; Goncalves, Alexandre; Poeta, Patricia; Igrejas, Gilberto
Antimicrobial resistance (AMR) is a worldwide problem with serious health and economic repercussions. Since the 1940s, underuse, overuse, and misuse of antibiotics have had a significant environmental downside. Large amounts of antibiotics not fully metabolized after use in human and veterinary medicine, and other applications, are annually released into the environment. The result has been the development and dissemination of antibiotic-resistant bacteria due to many years of selective pressure. Surveillance of AMR provides important information that helps in monitoring and understanding how resistance mechanisms develop and disseminate within different environments. Surveillance data is needed to inform clinical therapy decisions, to guide policy proposals, and to assess the impact of action plans to fight AMR. The Functional Genomics and Proteomics Unit, based at the University of Tras-os-Montes and Alto Douro in Vila Real, Portugal, has recently completed 10 years of research surveying AMR in bacteria, mainly commensal indicator bacteria such as enterococci and Escherichia coli from the microbiota of different animals. Samples from more than 75 different sources have been accessed, from humans to food-producing animals, pets, and wild animals. The typical microbiological workflow involved phenotypic studies followed by molecular approaches. Throughout the decade, 4,017 samples were collected and over 5,000 bacterial isolates obtained. High levels of AMR to several antimicrobial classes have been reported, including to beta-lactams, glycopeptides, tetracyclines, aminoglycosides, sulphonamides, and quinolones. Multi-resistant strains, some relevant to human and veterinary medicine like extended-spectrum beta-lactamase-producing E. coli and vancomycin-resistant enterococci, have been repeatedly isolated even in non-synanthropic animal species. Of particular relevance are reports of AMR bacteria in wildlife from natural reserves and endangered species. Future work awaits as this threatening yet unsolved problem persists.

Goncalves, A.; Poeta, P.; Monteiro, R.; Marinho, C.; Silva, N.; Guerra, A.; Petrucci-Fonseca, F.; Rodrigues, J.; Torres, C.; Vitorino, R.; Domingues, P.; Igrejas, G.
The Iberian wolf (Canis lupus signatus) is an endangered species native to the Iberian Peninsula. Due to their predatory and wild nature, these wolves serve as important indicators of environmental contamination by antimicrobial-resistant bacteria. beta-Lactam antibiotics like cefotaxime are the most commonly used antibacterial agents. Bacterial resistance to these antibiotics occurs predominantly through enzymatic inactivation by extended-spectrum beta-lactamases. Escherichia coli strain WA57, isolated from Iberian wolf feces, is a cefotaxime-resistant strain that produces extended-spectrum beta-lactamases. In this study, using 2D-GE combined with MS and bioinformatics, we report significant differences in the abundance of 40 protein spots (p < 0.01) from the extracellular, periplasmic, cytoplasmic, and membrane sub-proteomes and the whole-cell proteome of WA57 exposed and non-exposed to cefotaxime. A total of 315 protein spots were collected for protein identification. The comparative proteomics presented gives an overview of the complex changes in expression and metabolism that occur when WA57 is stressed with cefotaxime. Abundance of chaperone, porin and export proteins is particularly affected showing that the stress response and transport functions might directly influence the antibiotic resistance of this strain. Biological significance This study highlights the importance of proteomics in detecting protein expression changes in bacterial strains exposed to stress such as that caused by cefotaxime. This approach might help us understand which pathways form barriers for antibiotics. This article is part of a Special Issue entitled: Environmental and structural proteomics.