45 documents found, page 1 of 5
Effect of postharvest application of ethylene on the profile of phenolic acids ...
Costa, Daniela V. T. A.; Almeida, Domingos P. F.; Pintado, ManuelaBACKGROUND:Theblueberry is a fruit that hasbeen studied extensively for its healthbenefits,mainlydueto itshigh antioxidant activity. There is a strong correlation between antioxidant activity and total anthocyanin and phenolic compound content. Postharvest treatment using ethylene may be a factor affecting the anthocyanin content. The objective of this work was to analyze postharvest treatment using ethylene on...
Bioactive phytochemicals in apple cultivars from the Portuguese protected geogr...
Almeida, Domingos P. F.; Gião, Maria S.; Pintado, Manuela; Gomes, Maria HelenaPhytochemical composition and antioxidant activity of eight apple (Malus domestica) cultivars (“Casa Nova,” “Fuji,” “Golden Delicious,” “Granny Smith,” “Jonagored,” “Reinette Grise,” “Royal Gala,” and “Starking”) from the “Maçã de Alcobaça” protected geographic indication, Portugal, were characterized to support market segmentation based on phytochemical content. Total phenolics, flavonoids, and anthocyanin con...
Root-to-shoot ABA signaling does not contribute to genotypic variation in stoma...
Carvalho, Dália R. A.; Fanourakis, Dimitrios; Correia, Maria J.; Monteiro, José A.; Araújo-Alves, José Pedro L.; Vasconcelos, Marta W.High relative air humidity (RH 85%) during leaf expansion hampers stomatal responsiveness to closing stimuli, a genotype-dependent effect. Genotypes with reduced stomatal closure in response to closing stimuli (i.e., sensitive genotypes) show low bulk leaf abscisic acid concentration ([ABA]). We hypothesized that the amount of ABA produced in the roots and delivered with the transpiration stream to the leaves i...
Peach polyphenol and carotenoid content as affected by frozen storage and paste...
Oliveira, Ana L.; Alexandre, Elisabete M. C.; Coelho, Marta; Barros, Rui M.; Almeida, Domingos P. F.; Pintado, ManuelaThe profile of polyphenol and carotenoid of peach were analysed on fresh fruits, immediately after freezing or after pasteurization, and during frozen storage at -20 ºC for 360 days. Freezing did not affect the concentration of polyphenols or carotenoids. Pasteurization of fresh and frozen samples induced an increase in the extractability of chlorogenic acid (38% and 24%) and of zeaxanthin (336% and 127%) and a...
Root-to-shoot ABA signaling does not contribute to genotypic variation in stoma...
Carvalho, Dália R. A.; Fanourakis, Dimitrios; Correia, Maria João; Monteiro, José; Araújo-Alves, José Pedro L.; Vasconcelos, Marta W.High relative air humidity (RH >= 85%) during leaf expansion hampers stomatal responsiveness to closing stimuli, a genotype-dependent effect. Genotypes with reduced stomatal closure in response to closing stimuli (i.e., sensitive genotypes) show low bulk leaf abscisic acid concentration ([ABA]). We hypothesized that the amount of ABA produced in the roots and delivered with the transpiration stream to the leave...
Incorporation of strawberries preparation in yoghurt: impact on phytochemicals ...
Oliveira, Ana; Alexandre, Elisabete M. C.; Coelho, Marta; Lopes, Cláudia; Almeida, Domingos P. F.; Pintado, Manuela E.An immediate decrease in the total antioxidant activity (23%) and total phenolic content (14%) was observed after addition of strawberry preparations to yoghurt. The total anthocyanin content did not change immediately, but decreased 24% throughout the yoghurt shelf-life. The individual compounds, (+)-catechin (60%), (-)-epicatechin (60%), kaempferol (33%) and quercetin-3-rutinoside (29%) decreased after 24 h i...
Elevated air movement enhances stomatal sensitivity to abscisic acid in leaves ...
Carvalho, Dália R. A.; Torre, Sissel; Kraniotis, Dimitrios; Almeida, Domingos P. F.; Heuvelink, Ep; Carvalho, Susana M. P.High relative air humidity (RH ≥ 85%) during growth leads to stomata malfunctioning, resulting in water stress when plants are transferred to conditions of high evaporative demand. In this study, we hypothesized that an elevated air movement (MOV) 24 h per day, during the whole period of leaf development would increase abscisic acid concentration ([ABA]) enhancing stomatal functioning. Pot rose 'Toril' was grow...
Effect of modified atmosphere on phytochemical profile of pasteurized peach purées
Oliveira, Ana; Coelho, Marta; Alexandre, Elisabete; Gomes, Maria Helena; Almeida, Domingos P. F.; Pintado, ManuelaPeach phytochemical profile was analysed during 90 days storage under three different gas mixtures: 10 kPa O2+90 kPa N2, 100 kPa N2 and air (78 kPa N2+21 kPa O2+0.03 kPa CO2) for both 4 and 23 °C. The antioxidant activity increased when peach purée was stored under air at 4 °C and 100 kPa N2 at 23 °C, while total phenolic content was not affected by atmospheres. Total carotenoids were more stable for 100 kPa N2...
Phytochemicals preservation in strawberry as affected by pH modulation
Oliveira, Ana; Gomes, Maria Helena; Alexandre, Elisabete M. C.; Poças, Fátima; Almeida, Domingos P. F.; Pintado, ManuelaStrawberries purees are incorporated in foods and subjected to pH modulation according to the expected final food matrix. The effect of pH on strawberry polyphenols stored at 4 and 23 degrees C for 90 days was evaluated. Total antioxidant activity and total phenolics content were only affected by time according to a first order model. The pH 4.5 induced higher decrease in (-)-epigallocatechin gallate (71% and 7...
Long-term frozen storage and pasteurization effects on strawberry polyphenols c...
Oliveira, Ana; Coelho, Marta; Alexandre, Elisabete M. C.; Almeida, Domingos P. F.; Pintado, ManuelaThe profile of the strawberry polyphenols was analysed on fresh strawberry, immediately after freezing or after pasteurization and during frozen storage of strawberry at -20 A degrees C for 360 days. Freezing increased the extractability of (-)-epigallocatechin gallate (60 %), (-)-epicatechin (48 %) and ellagic acid (51 %) and decreased the pelargonidin-3-glucoside (18 %). Direct pasteurization of fresh strawbe...