Browsing by Author "Rodrigues, Ana"
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- Different approaches to Olive Pomace valorisationPublication . Cordeiro, Ana; Lamas, Sandra; Rodrigues, Ana; Cadavez, Vasco; Silvério, Sara; Peres, António M.; Rodrigues, Lígia R.; Amorim, CláudiaOlive pomace (OP) is a substantial by-product, rich in lignocellulosic materials and water, obtained following the extraction of olive oil. It comprises the following components: olive skins, pulp, seeds, and stones. As global olive oil production continues to rise, the management and utilisation of OP have become increasingly important from both an economic and an environmental perspective [1]. In this study, the OP was chemically characterized and its potential as a source of value-added compounds was evaluated. For this purpose, several extraction studies were preformed, namely lipid extraction using petroleum ether, phenolic compound extraction with ethanol, and free sugar extraction with water using a Soxhlet system (Figure 1). These extractions allowed to recover 11.1 ± 0.3 % (w/w) of lipids, different types of phenolic compounds and oligosaccharides. Phenolic compounds are widely recognized for their health-promoting properties (e.g. antioxidant, anti-inflammatory, cancer prevention or antimicrobial activity) and have been the subject of extensive research. Oligosaccharides (OS) are short chains of monosaccharide units linked by glycosidic bonds. The ingestion of these compounds has been demonstrated to confer a multitude of salutary effects, predominantly due to their function as prebiotics and their capacity to regulate gut health and influence overall metabolic processes. Enzymatic hydrolysis was also performed using commercial xylanase from Trichoderma reesei, under optimal conditions (pH 4.5, 40°C, 150 rpm) to evaluate the potential of OP to produce xylo-based oligosaccharides [2]. The hydrolysis process was monitored through Thin Layer Chromatography (TLC), High-Performance Liquid Chromatography (HPLC) using different columns, and the Dinitrosalicylic acid (DNS) method (Figure 2). The results indicated the production of xylo-based oligosaccharides, validating the proposed bioprocess as a viable method for XOS production from OP. This approach not only provides value-added to OP but also aligns with sustainable waste management practices.
- Genetic variation of cork oak a tool for improving regeneration of cork oak woodlandsPublication . Almeida, Maria Helena; Aranda, Ismael; Chambel, Maria Regina; Silva, F. Costa e; Dettori, Sandro; Faria, Carla Maria Gomes Marques; Filigheddu, Maria Rosaria; Fernández, Elena; Khaldi, Abedelhamid; Patrício, Maria Sameiro; Perez, Felipe; Ramirez-Valiente, José Alberto; Rodrigues, Ana; Sampaio, Teresa; Varela, CarolinaThe European Academies' Science Advisory Council (2017) reports that the Mediterranean forest is already being affected by climate change (IPCC, 2014) and cork oak woodlands are particularly vulnerable to high-end climate scenarios that go above the Paris Agreement 2° C increase in temperature. Since longer, more frequent, and more intense drought periods are expected, stress caused by the expansion of arid and semi-arid climate will affect the species distribution. Consequently, not only established stands may be prone to tree mortality, but also the current reforestation effort may be jeopardized by low survival rates attributed to the use of unsuitable genetic material. It is expected that, through genetic adaptation and/or phenotypic plasticity, cork oak populations may have developed significant differences in fitness and the traits related to it. In this context, provenance and progeny trials are the best resource of material to assess the variability between and within populations from seed sources sampled in a wide range of locations (stands) covering the geographical distribution of the species. Profiting from the multi-locality provenance and progeny trials belonging to a Network, established in 1998, in the initiative frame of FAIR I CT 0202 for the evaluation of genetic resources of cork oak for appropriate use in breeding and gene conservation strategies”, where 35 cork oak populations covering all the natural distribution area are represented. The provenance trials that where set up in different countries are entering now the age of first debarking and this should allow to have first data about the influence of genetics on production by different site qualities. INCREDIBLE project should document this knowledge
- Geographic variation in cork oak and its implications for expected impacts of climate changePublication . Rodrigues, Ana; Sampaio, Teresa; Silva, João Costa e; Patrício, Maria Sameiro; Silva, Filipe Costa e; Faria, Carla Maria Gomes Marques; Correia, António H.; Varela, Carolina; Pereira, João Santos; Almeida, Maria HelenaCork oak (Quercus suber L.) is a protected tree species in Portugal, being also the source of raw material for the cork industry, a major player in Portuguese economy (representing 3% of GDP in 2010). The future climatic scenarios for Portugal point to an increase in average summer temperatures from 0.3 to 0.7ºC between 2016 and 2035, and up to 4.6ºC until 2100. In addition, precipitation estimates suggest a reduction of annual rainfall from 20 to 40%, especially in southern Portugal. Water stress will, therefore, be a leading constraint to primary production. The combined effects of drought and high temperatures will lead to decreases in carbon assimilation and increases in tree mortality, and consequently current reforestation efforts will need to account for these expected adverse outcomes through the sustainable use of suitable genetic material. There are several reasons that can be highlighted to emphasize the need for an efficient management of cork oak genetic resources in Portugal, namely: i) to avoid cork import, and thus to increase cork production to meet the industry demands; ii) to overcome a generally poor area of natural regeneration, which does not help to ensure an in situ conservation of genetic resources; iii) to deploy adapted genetic material for afforestation/reforestation; and iv) to develop a gene resources conservation program, as cork oak is a vital component of agro-silvopastoral systems in the Mediterranean region. Given the broad native range of the species, involving significant environmental and geographic gradients, a high level of genetic variation can be expected. It is possible that disruptive selection has caused a large differentiation in adaptive traits among populations, namely in the ability to tolerate different environmental stress events (e.g. drought and frost) and to cope with pests and diseases. Between 1998 and 2011, we have collected data involving survival, growth, phenology and water-use efficiency traits from five common-garden provenance trials (including family structure in two of the trials), that were established in Portugal under a concerted action launched by the EUFORGEN’s network. These multi-site field experiments are based on up to 35 tested provenances covering the entire natural distribution of cork oak, and results obtained from the genetic evaluation of the trials have indicated significant differences among populations for all the measured traits at all observed ages. Four of the tested provenances (Alpujarras – Haza de Lino, Puglia – Lucci - S. Teresa, Landes - Soustons, Rif Occidental – Ain Rami) were then chosen according to their contrasting field performance for growth, phenology and water-use efficiency (WUE), and were further evaluated under controlled-environment conditions where drought stress was induced. In this context, the main drivers of drought adaptation appeared to be early stomatal closure and root investment, which also showed significant differences among the selected provenances. The responses to drought over time also varied among these studied populations, and seemed to be related to their differences in growth rhythm. The Ain Rami population seemed to be most prone population to endure drought conditions. Facing a water deficit scenario this population, with highest growth, showed a higher investment on roots compared to the Haza de Lino population, that even under optimal hydration status, had lower biomass values, more reduced transpiration area (smallest size, with lowest Specific Leaf Area), leading to a lower water consumption. This population showed a delay in onset of stress when compared to other populations, only revealed no stomatal limitations with high stress levels. Furthermore, Ain Rami showed higher WUE under drought conditions both in the field trials and under controlled conditions, but average WUE in wet conditions. The results from the field and controlled-environment experiments were consistent in that geographic origin had an important influence on the performance of fitness surrogates and functional traits, and thus providing a strong indication that seed origin must be considered in cork oak reforestation programs.