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- Profiling of lipophilic and phenolic phytochemicals of four cultivars from cherimoya (Annona cherimola Mill.)Publication . Santos, Sónia A. O.; Vilela, Carla; Camacho, João F.; Cordeiro, Nereida; Gouveia, Manuela; Freire, Carmen S. R.; Silvestre, Armando J.D.The lipophilic and phenolic extractives of the ripe mesocarp of four cherimoya cultivars ('Perry Vidal', 'Mateus I', 'Mateus III' and 'Funchal') from Madeira Island, were studied for the first time. The predominant lipophilic compounds are kaurene diterpenes (42.2-59.6%), fatty acids (18.0-35.6%) and sterols (9.6-23.7%). Kaur-16-en-19-oic acid is the major lipophilic component of all cultivars accounting between 554 and 1350mgkg(-1) of dry material. The studied fruits also contain a high variety of flavan-3-ols, including galloylated and non-galloylated compounds. Five phenolic compounds were identified for the first time: catechin, (epi)catechin-(epi)gallocatechin, (epi)gallocatechin, (epi)afzelechin-(epi)catechin and procyanidin tetramer. 'Mateus I' and 'Mateus III' cultivars present the highest content of phenolic compounds (6299 and 9603mgkg(-1) of dry weight, respectively). These results support the use of this fruit as a rich source of health-promoting components, with the capacity to prevent or delay the progress of oxidative-stress related disorders.
- In vitro evaluation of nematicidal properties of Solanum sisymbriifolium and S. nigrum extracts on Pratylenchus goodeyiPublication . Pestana, Margarida; Rodrigues, Mónica; Teixeira, Lucília; Abrantes, Isabel de O.; Gouveia, Manuela; Cordeiro, NereidaThe root-lesion nematode, Pratylenchus goodeyi, is among the most economically damaging parasites of banana plants. Nematode control can benefit from searching for novel bio-nematicides. The present study was carried out to assess the potential nematicidal properties of two Solanum species (Solanum sisynibriífolíum and S. nigrum) against P. goodeyi, using dichloromethane, acetone, ethanol and either cold or hot water extracts of the plants. Water extracts of both plants at a concentration of 10 mg ml" ' greatly affected nematode movement and also caused mortality. The analysis of sequential extracts at the same experimental concentrations showed that, although water extracts affect nematode mobility and mortality, the acetone extract from S. nigrum was the most efficient, causing 100% mortality after 23 h exposure. The results showed that S. sísymbríífolíum and S. nigrum extracts contain chemical components that induce morphological changes in the body structure of the root-lesion nematode, affect mobihty and cause mortality. The nematostatic and nematicidal potential of the extracts described herein merit further studies to find novel bio-nematicides against the root-lesion nematode.
- Molecular cloning and characterization of cDNAs encoding cytosolic malate dehydrogenase and vacuolar (H+)-ATPase in Annona cherimola and their expression during postharvest ripeningPublication . Gouveia, Manuela; Rodrigues, Mónica; Teixeira, Lucília; Cordeiro, NereidaThis study aims to investigate the expression of two cherimoya genes putatively related to fruit ripening. Two full-length cDNAs encoding cytosolic NAD-dependent malate dehydrogenase (AccytMDH) and vacuolar (H+)-ATPase c subunit (AcVHA-c) were isolated from Annona cherimola using the reverse transcriptase polymerase chain reaction (RT- PCR) and rapid amplification of cDNA ends (RACE). The AccytMDH codes for a 332 amino acid polypeptide with a predicted molecular mass of 35.6 kDa. The deduced amino acid sequence for AccytMDH shared high identity with other plant homologous malate dehydrogenase proteins. The AcVHA-c encodes a proteolipid subunit of the V-type proton ATPase with 166 amino acids (16.7 kDa). Comparison of the deduced amino acid sequence from AcVHA-c revealed four transmembrane domains highly conserved among plant counterparts. The expression of AccytMDH and AcVHA-c, assessed by semi-quantitative RT-PCR showed that there is an increase in the accumulation of transcripts during postharvest ripening, although not correlated by a significant upsurge of titratable acidity they might contribute to organic acid accumulation and translocation during postharvest ripening of cherimoya in association with other enzymes and carriers. By using AccytMDH and AcVHA-c as molecular targets new strategies can be exploited to get a clear picture in the ripening of cherimoya.
- Changes in the mesocarp of Annona cherimola Mill. ‘Madeira’ during postharvest ripeningPublication . Cordeiro, Nereida; Sousa, Lúcilia; Freitas, Nélia; Gouveia, ManuelaPhysicochemical changes during postharvest ripening of cherimoya (Annona cherimola Mill. ‘Madeira’), were investigated to follow the principal modifications occurring during this process and to determine nutritional value. Fruit harvested atthe mature green stage were analyzed during ripening using standard methods. Significant (P < 0.05) changes in chlorophyll, starch, titratable acidity, total free sugars and uronic acids were obtained, but no significant changes were found in ash, protein, lignin and lipid contents during ripening. The most obvious changes were chlorophyll degradation, an accentuated decrease of starch and an increase in total free sugars, with glucose the predominant sugar in the mesocarp, as revealed by GC analyses. Firmness loss was mainly attributed to depolymerization of pectin and lipid deterioration rather than hemicellulose degradation. Results also showed that the cherimoya variety evaluated in this study is a good source of minerals (mainly potassium), palmitic acid, linoleic acid, -linolenic acid and sitosterol.
- Ipomoea batatas (L.) Lam.: a rich source of lipophilic phytochemicalsPublication . Cordeiro, Nereida; Freitas, Nélia; Faria, Marisa; Gouveia, ManuelaThe lipophilic extracts from the storage root of 13 cultivars of sweet potato (Ipomoea batatas (L.) Lam.) were evaluated by gas chromatography-mass spectrometry with the aim to valorize them and offer information on their nutritional properties and potential health benefits. The amount of lipophilic extractives ranged from 0.87 to 1.32% dry weight. Fatty acids and sterols were the major families of compounds identified. The most abundant saturated and unsaturated fatty acids were hexadecanoic acid (182-428 mg/kg) and octadeca-9,12-dienoic acid (133-554 mg/kg), respectively. β-Sitosterol was the principal phytosterol, representing 55.2-77.6% of this family, followed by campesterol. Long-chain aliphatic alcohols and α-tocopherol were also detected but in smaller amounts. The results suggest that sweet potato should be considered as an important dietary source of lipophilic phytochemicals.
- Nematicidal activity of Solanum sisymbriifolium and S-nigrum extracts against the root-lesion nematode Pratylenchus goodeyiPublication . Pestana, M.; Rodrigues, M.; Teixeira, L.; Abrantes, I. M. de O.; Gouveia, M.; Cordeiro, NereidaThe root-lesion nematode, Pratylenchus goodeyi, is a parasite of banana plants, frequently detected in Madeira Island (Portugal) affecting culture development and consequently the production, with economical damages. To identify the phytochemicals of Solanum sisymbriifolium and S. nigrum with nematicidal properties and determine the effect of those components on P. goodeyi, an extraction sequence of at least 10 hours each from dried plants was used. The chosen solvent sequence was: dichloromethane, acetone, ethanol and water. According to the results, both plants have in their composition chemical components mainly found in water extracts, which affects the mobility and mortality of the root-lesion nematode. S sisymbriifolium and S. nigrum have potential to be used as a natural and environmentally friendly nematicide to control P. goodeyi.