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- Recursos fitogenéticosPublication . Jesus, Isidoro; Carvalho, Miguel Ângelo Almeida Pinheiro deEste capítulo aborda os recursos fitogenéticos do cas- tanheiro no Arquipélago da Madeira e as metodologias utilizadas na sua avaliação. Os aspectos relacionados com as metodologias de caracterização destes recursos são analisados, nomeadamente os diferentes descritores morfológicos, bioquímicos e moleculares utilizados e as técnicas que dão suporte à avaliação dos mesmos. São apresentados os resultados preliminares da avaliação dos recursos do castanheiro, desenvolvidos com base num estudo de caracterização morfológica, sendo propostas 7 variedades regionais: curral, coração de boi, preta, mansinha, lisboa, santo antónio e formosa. Esta avaliação preliminar dos recursos do castanheiro deverá, no futuro, ser fundamentada com base em dados bioquímicos e moleculares. Por último, são abordadas as perspectivas de protecção desta cultura e da valorização da sua produção na Madeira.
- História, importância e distribuição do castanheiroPublication . Jesus, Isidoro; Carvalho, Miguel Ângelo Almeida Pinheiro deO presente capítulo aborda a história e a importância da cultura do castanheiro no Arquipélago da Madeira, assim como a sua distribuição actual na ilha da Madeira. Os aspectos relacionados com a distribuição geográfica da cultura e as condições edafo-ecológicas, em que se desenvolvem as principais cultivares desta espécie agro- -florestal, são caracterizados com o objectivo de explicar a diversidade de recursos genéticos existentes numa região de pequenas dimensões.
- Effects of Melatonin-aided therapy on the Glutathione antioxidant system activity and liver protectionPublication . Popov, Serguey S.; Shulgin, Konstantin K.; Popova, Tatyana N.; Pashkov, Aleksander N.; Agarkov, Aleksander A.; Carvalho, Miguel A. A. Pinheiro deAcute hepatitis results from oxidative stress triggered by hepatotoxic drugs causing liver injury and the activation of caspases cascade. The glutathione antioxidant system protects against reactive oxygen species and mitigates development of these processes. The effectiveness of silymarin, a polyphenolic flavonoid, essenthiale, composed of phosphatidyl choline, and melaxen, a melatonin-correcting drug, as hepatoprotectors has been investigated. The variation of 6-sulfatoxymelatonin (aMT6s), resulting from the biotransformation of melatonin, and GSH has been measured. The activities of caspase-1 and caspase-3, glutathione antioxidant system, and NADPH-generating enzymes were determined. The aMT6s decreases in patients with drug hepatitis and recovers with administration of mexalen. GSH increased in the presence of the studied hepatoprotectors. Pathologically activated caspase-1 and caspase-3 decreased their activities in the presence of hepatoprotectors with melaxen showing the highest effect. The positive effect of melatonin appears to be related to the suppression of decompensation of the glutathione antioxidant system functions, recovery of liver redox status, and the attenuation of inhibition of the NADPH supply.
- Variation of carbon and isotope natural abundances (δ15N and δ13C) of whole-plant sweet potato (Ipomoea batatas L.) subjected to prolonged water stressPublication . Gouveia, Carla S.S.; Ganança, José F.T.; Slaski, Jan; Lebot, Vincent; Carvalho, Miguel Â. A.Sweet potato (Ipomoea batatas L.) is an important crop in the world, cultivated in temperate climates under low inputs. Drought changes the plant biomass allocation, together with the carbon and nitrogen isotopic composition (δ13C and δ15N), whose changes are faintly known in sweet potato crops. Here, we show the biomass allocation of eight sweet potato accessions submitted to drought during 3 months, using the δ13C, δ15N, carbon isotope discrimination (Δ13C), total carbon (TC) and water use efficiency (WUE) traits. The tolerant accessions had improved WUE, with higher TPB and TC. Storage roots and shoots had a heavier δ13C content under drought stress, with greater 13C fixation in roots. The Δ13C did not show a significant association with WUE. The δ15N values indicated a generalised N reallocation between whole-plant organs under drought, as a physiological integrator of response to environmental stress. This information can aid the selection of traits to be used in sweet potato breeding programs, to adapt this crop to climate change.
- Phytogeographical origin of Madeiran common beans based on phaseolin patternsPublication . Silva, Emanuel Marques da; Correia, Anísia Soraia Abreu; Lopes, Nuno Alexandre Amaral; Nóbrega, Humberto Gil Moreira; Ganança, José Filipe Teixeira; Domingues, Ana Maria; Khadem, Manhaz; Slaski, Jan Jacek; Carvalho, Miguel Ângelo Almeida Pinheiro deThe objective of this work was to determine the geographic origin of the Madeiran common bean (Phaseolus vulgaris) gene pool. Phaseolin patterns of 50 accessions representing the diversity of common bean collected in Madeira, Portugal, and conserved in the ISOPlexis Germplasm Bank, were analysed using the Experion automated electrophoresis system, based on lab-on-a-chip technology. Five common bean standard varieties with typical phaseolin patterns were used to determine the phytogeographical origin of the Madeiran common bean accessions. Ninety two percent of the accessions exhibited a phaseolin pattern consistent with the one of common bean types belonging to the Andean gene pool, while the origin of the remaining 8% of the accessions was indistinguishable. The application of a similarity coefficient of 85%, based on Pearson correlations, increases the number of accessions with uncertain pattern. The analytical approach used permitted the determination of the origin of the common bean gene pool, which is Andean in 98% of the cases, and clustering of the observed variability among the Madeiran common beans.
- Contributo para o conhecimento da agrodiversidade no concelho de Santa Cruz, MadeiraPublication . Carvalho, Miguel A. A. Pinheiro de; Ragonezi, Carla; Macedo, Fabrício Lopes de; Antunes, Gonçalo; Freitas, Gregório; Nóbrega, HumbertoO presente trabalho procura analisar as alterações sofridas pela agrodiversidade no território do Santa Cruz. Este concelho localizado na costa sul da Madeira tem 81,5 km2, quatro patamares bioclimáticos e numerosas unidades agroecológicas (UAE). A evolução da agrodiversidade iniciou-se, com o povoamento do Arquipélago, descoberto inabitado em 1418. A agrodiversidade biofísica, específica e intraespecífica aumentou e diversificou-se, devido à construção de agrossistemas, introdução de culturas, sucessão de ciclos agrícolas, adaptação às condições agroecológicas, aparecimento de pragas e doenças e pela ação do homem. Os registos históricos indicam a introdução de um elevado número de culturas, bem como a utilização de 72 espécies agrícolas, no concelho. E, indicam como fundamentais no povoamento e economia as culturas do trigo e as cerealíferas (cevada, centeio), cana-sacarina, vinha e sumagre. Várias outras culturas desempenharam um papel importante na economia do concelho, sendo cultivadas para fins alimentares, comerciais, industriais, culturais ou religiosos. A adaptação destas espécies aos agrossistemas e às condições agroecológicas deu origem a um número indeterminado de variedades locais. Apesar das limitações da documentação disponível, foram encontradas referências a variedades locais cuja cultura remonta há 140 a 500 anos, nomeadamente o Trigo da Serra, castas Malvasia e Tinta Antiga de Gaula, pêra Caniça, Banana da terra, feijão Corno de carneiro e Couve de João Ferino, que podem ser relacionadas com o historial do concelho. Porém, desde meados do século XX, a agrodiversidade sofreu uma drástica redução com a diminuição das áreas cultivadas, o abandono de várias espécies agrícolas e a extinção de variedades locais. A análise desta agrodiversidade foi realizada, a fim de apurar as alterações históricas e geográficas ocorridas na agrodiversidade em onze culturas representativas do concelho, visando a sustentabilidade agronómica.
- Constructing ethanol-derived bioactive extracts using the brown seaweed Zonaria tournefortii (J.V.Lamouroux) Montagne performed with Timatic extractor by means of response surface methodology (RSM)Publication . Nunes, N.; Valente, S.; Ferraz, S.; Barreto, Maria Carmo; Carvalho, M.A.A. Pinheiro deUnderstanding the biochemical and antioxidant composition and capacity of a target biomass is the first step to its selectivity as functional food which can enhance the ability to promote health by reducing the risk of chronic diseases. The main purpose of this work was to employ response surface methodology (RSM) to determine the effect of the independent variables, % of ethanol (50–96%), time of sonication (0–20 min), and number of extraction cycles (6–18 cycles) in the primary extract of brown seaweed Zonaria tournefortii, studying the yield variation of some bioactive compounds, assessing the potential of these bioextracts to integrate as a natural additives or supplements in the functional food industry. The extractions were performed employing “Green Chemistry” techniques executed with the Timatic extractor, which applied pressurized ethanol solution at a maximum pressure of 8.5 bar through milled dehydrated biomass in the extraction vessel. Several parameters were assessed in the primary bioactive extract which included extract yield (11.56–28.49 g (100 g)−1 dw), total chlorophyll content (0.14–1.42 g (100 g)−1 dw), total carotenoid content (0.35–0.80 g (100 g)−1 dw), total fucoxanthin content (0.04–0.13 g (100 g)−1 dw), total phenolic content (3.58–5.84 g (100 g)−1 dw), total flavonoid content (0.22–4.70 g (100 g)−1 dw), DPPH (56.05–76.45%), and reducing activity (3.83–6.04 g (100 g)−1 dw). A second objective was to determine the suitability of the residue for subsequent extraction of valuable compounds such as fucoidan (4.87 to 6.59 g (100 g)−1 dw) and cellulose (18.88 to 20.27 g (100 g)−1 dw), implementing the first step to a biorefinery strategy, using a cascade approach.
- Different seaweeds use for iodine deficiency overcomePublication . Ferraz, Sónia; Ragonezi, Carla; Nunes, Nuno; Valente, Sofia; Carvalho, Miguel A. A. Pinheiro deIodine deficiency is one of the three most common nutritional deficiencies worldwide and is a global public health problem that affects particularly the young children, pregnant women and elderly. The consequences of iodine deficiency disorder (IDD) include goiter and cretinism. The traditional consumption of iodine via supplemented salt should be monitored to reduce population sodium intake due to hypertension problems and the uncertain bioavailability of iodine in the supplemented salt. One approach for an effective and cost-efficient iodine supplementation is the use of seaweeds in food intake. Seaweeds, among all foods, are the most famous and reliable source of natural iodine. In this minireview we pretend to explore the different uses of seaweeds to fill the iodine deficiency and improve life quality.
- Nutraceutical potential of Asparagopsis taxiformis (Delile) Trevisan extracts and assessment of a downstream purification strategyPublication . Nunes, N.; Valente, S.; Ferraz, S.; Barreto, Maria Carmo; Carvalho, M. A. A. Pinheiro deThe main goal of the present work was to determine the nutraceutical potential of Asparagopsis taxiformis D. extracts from Madeira Archipelago south coast. Extraction methodologies consisted either/or in 72 hours stirring, at room temperature (M1), or 6 cycles of Soxhlet extraction (M2), both with re-extraction. Solvents used were distilled water, ethanol, methanol and ethyl acetate. M1 allowed to obtain the highest values for extraction yield (31.65 g.100g 1 dw) using water, whereas iodine content (3.37 g.100g 1 dw), TPC (1.71 g GAE.100g 1 dw) and chlorophyll a (45.96 mg.100g 1 dw) were obtained using ethanol, and TCC (36.23 mg.100g 1 dw) with methanol. Extracts that showed higher reduction activity in M1 were derived from ethanol extraction (1,908 mg AAE.100g 1 dw). Water and ethanol were the best solvents for higher DPPH scavenging activity in M2, both with same result (IC50 1.37 mg.mL 1 ). The lowest value of IC50 for chelating activity (1.57 mg.mL 1 ) was determined in M1, using ethyl acetate. The remaining residue was used to obtain other products, i.e. lipid extraction (M1, 2.05 g.100g 1 dw), carrageenans (M2, 21.18 g.100g 1 dw) and cellulose (M1, 23.81 g.100g 1 dw) with subsequent FTIR ATR analysis. Our results show that A. taxiformis is a valuable source of bioactive compounds. The M1 extraction methodology using ethanol is the most effective solvent to produce an iodine rich bioactive extract with potential of being used as a nutraceutical supplement. Also, we have demonstrated a possible downstream strategy that could be implemented for multiple compound extraction from A. taxiformis residue. This has a vital importance for future feasibility, when using this biomass as an industrial feedstock for multiple products production. Statistical analysis, using SPSS 24.0, was also performed and important correlations were found between assays and methods.
- Screening for drought tolerance in thirty three Taro cultivarsPublication . Ganança, José F. T.; Freitas, José G. R.; Nóbrega, Humberto G.M.; Rodrigues, Vanessa; Antunes, Gonçalo; Gouveia, Carla S. S.; Rodrigues, Miguel; Chair, Hana; Carvalho, Miguel A. A. Pinheiro de; Lebot, VincentTaro [Colocasia esculenta (L.) Schott] is a root crop which is an important staple food in many regions of the world, producing 10.5 million tonnes on 1.4 million hectares a year. The crop is cultivated in wet (rain fed) or irrigated conditions, requiring on average 2,500 mm water per year, and in many countries it is cultivated in flooded plots. It is estimated that taro production could decrease by 40% as a result of the increase in drought and other severe events. In this work, thirty three accessions, including local cultivars, selected and hybrid lines were submitted to long duration drought stress and screened for tolerance. Twelve physiological, morphological and agronomic traits were measured at harvest, and subject to multivariate analysis. Stress indices, Water Use Efficiency and Factorial Analysis were useful for discriminating accessions regarding drought tolerance and yield stability, and drought tolerant and susceptible cultivars were identified. Our results confirm that different taro cultivars have different drought avoidance and tolerance strategies to cope with water scarcity. Better yield performers minimised biomass and canopy loss, while tolerance was observed in cultivars that presented low potential yield, but efficiently transferred resources to enhance corm formation. Among the 33 accessions, two local cultivars showed high yield stability and could be considered as suitable parents for breeding programs, while two others are well adapted to drought, but with overall low yield potential.