Browsing by Author "Petropoulos, Spyridon A."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
- The Effect of Cropping System and Irrigation Regime on the Plant Growth and Biochemical Profile of Cichorium spinosumPublication . Paschoalinotto, Beatriz H.; Polyzos, Nikolaos; Liava, Vasiliki; Mandim, Filipa; Pires, Tânia C.S.P.; Añibarro-Ortega, Mikel; Dias, Maria Inês; Barros, Lillian; Petropoulos, Spyridon A.This study evaluated the effects of three irrigation treatments (control (rain-fed plants), deficit irrigation (DI: 50% of maximum field capacity), full irrigation (FI: 100% of maximum field capacity)), and two crop-management treatments (with or without crop rotation with bean, CR, and NCR, respectively) on the plant growth and chemical composition of C. spinosum. The results indicated that deficit irrigation combined with crop rotation increased the weight of leaves per plant, followed by rain-fed plants for the same crop-management treatment. Additionally, these two factors significantly influenced the nutritional profile, free sugars, and organic acid content in a variable manner. Moreover, the control treatment and deficit irrigation increased the content of K, Na, and Mg, which are highly mobile nutrients, whereas the levels of moderately mobile nutrients such as Fe, Mn, Cu, and Zn decreased. Deficit irrigation without crop rotation significantly increased the content of total tocopherols, followed by deficit irrigation with crop rotation and full irrigation without crop rotation. The main fatty acids were α-linolenic acid (C18:3n3), followed by palmitic acid (C16:0) and linoleic acid (C18:2n6), while the control and deficit irrigation treatments combined with crop rotation increased PUFA and decreased SFA content. Furthermore, deficit irrigation and crop rotation induced the accumulation of phenolic compounds, flavonoids, and phenolic acids, especially the content of the major compounds (e.g., chicoric acid, quercetin-O-hexurunoside, and luteolin-O-hexurunoside). The leaf extracts exhibited varied antioxidant activity (assessed by TBARS and OxHLIA assays), and antimicrobial activity. On the other hand, no antifungal, antiproliferative (except for AGS cell line), hepatotoxic, or anti-inflammatory effects were recorded. In conclusion, the combination of deficit irrigation and crop rotation with bean positively affected the quality traits and the fresh weight of leaves, thus suggesting that such eco-friendly practices could have beneficial effects in the cultivation of C. spinosum plants within the context of climate-change mitigation strategies.
- Enhancing Tomato Growth and Quality Under Deficit Irrigation with Silicon ApplicationPublication . Añibarro-Ortega, Mikel; Pereira, Alexis; Pinela, José; Liava, Vasiliki; Chaski, Christina; Alexopoulos, Alexios A.; Barros, Lillian; Petropoulos, Spyridon A.This study aimed to evaluate the effect of two irrigation systems (deficit irrigation (DI)—70% of field capacity—and full irrigation (FI)—100% of field capacity) and a biostimulant formulation (silicon (Si) and calcium (Ca) at four different rates) on the chemical composition and fruit quality of greenhouse-grown tomatoes. Deficit irrigation and biostimulant application influenced the proximate composition of tomato fruits. Fructose and glucose were the main soluble sugars, while malic and citric acids were the predominant organic acids. Free sugar and organic acid content increased under DI and biostimulant applications. In contrast, deficit irrigation combined with biostimulant application decreased α-tocopherol levels. In terms of carotenoids, lycopene and β-carotene concentrations were higher under full irrigation. The main fatty acids were palmitic (C16:0) and linoleic (C18:2n6) acids, with saturated (SFA) and polyunsaturated (PUFA) fatty acids being the main classes. Moreover, biostimulant applications reduced the total phenolic content regardless of the irrigation regime, whereas the flavonoid content increased when biostimulants were applied under FI conditions. Regarding antioxidant activity (assessed by TBARS and OxHLIA assays), a variable response to irrigation and biostimulant application was observed. In conclusion, the application of Si and Ca under DI showed promising results in terms of yield and quality of tomato fruit and it could be considered a sustainable strategy to mitigate adverse effects of climate change on horticultural crops.
- Exploring the Biochemical Profile of Beta vulgaris L.: A Comparative Study of Beetroots and Swiss ChardPublication . Almeida, Daiana; Petropoulos, Spyridon A.; Silveira, Tayse F. F. da; Pires, Tânia C.S.P.; Ferreira, Isabel C.F.R.; Fernandes, Ângela; Barros, LillianIn this study, leaves and roots from three beetroot cultivars (cv. Albina Vereduna (white roots), cv. Burpee’s Golden (golden roots), and cv. Pablo F1 (red roots)), as well as Swiss chard leaves (also known as “rhubarb chard”, or Beta vulgaris subsp. cicla var. flavescens) were evaluated in terms of their chemical profile and bioactive properties. Roots were characterized by high carbohydrate content, which also contributed to greater energy values. In contrast, fibers were the predominant macronutrient in leaves, followed by carbohydrates. In both leaves and roots, the most abundant organic acids were quinic and oxalic, while the major free sugar was sucrose. The profile of fatty acid varied between the studied plant parts, with saturated fatty acids prevailing in root samples, while leaves exhibited higher levels of polyunsaturated fatty acids. Regarding phenolic composition, a total of 19 compounds were tentatively identified in leaves (including derivatives of vitexin, isorhamnetin, quercetin, and ferulic, sinapic, and p-coumaric acids), while the roots exhibited a less diverse composition, with a total of eight compounds identified (e.g., derivatives of ferulic, sinapic, p-coumaric and caffeic acids). A total of eight betalains were also identified, out of which seven were classified as betacyanins and one as betaxanthin. The leaves of Swiss chard presented compounds from both classes, while the roots and leaves of cv. Pablo F1 were characterized only by the presence of betacyanins, and those of cv. Burpee’s Golden only by betaxanthin. All samples exhibited relevant activity against Y. enterocolitica, L. monocytogenes, and S. aureus, although leaf samples demonstrated better antioxidant capacity. In conclusion, beetroot leaves outperformed their corresponding roots in terms of chemical composition, antioxidant, and antimicrobial activity, suggesting their high potential as nutrient-rich and functional ingredients in a diverse and well-balanced diet.
- Nutritional, Chemical, Antioxidant and Antibacterial Screening of Astragalus cicer L. and Astragalus glycyphyllos L. Different Morphological PartsPublication . Shahrivari-Baviloliaei, Saba; Konopacka, Agnieszka; Pascoalino, Liege; Reis, Filipa S.; Kunkowski, Dawid; Petropoulos, Spyridon A.; Konieczynski, Pawel; Orhan, Ilkay Erdogan; Plenis, Alina; Viapiana, AgnieszkaThe chemical composition and biological activity of A. glycyphylos and A. cicer are scarcely investigated. In this study, the nutritional and chemical profiles of A. cicer and A. glycyphyllos, considering their different morphological parts (leaves, fruits and roots), were assessed together with their antioxidant and antibacterial potential. Our results showed that carbohydrates are the major macronutrients in both Astragalus species (above 62 g/100 g dry weight—DW). High amounts of ash (above 4.6 g/100 g DW) and protein (above 13.0 g/100 g DW) were also identified, particularly in leaves and fruits of A. cicer and A. glycyphyllos. Moreover, A. cicer was richer in sugars than A. glycyphyllos, while roots of both Astragalus species were the richest of fatty acids. Ten phenolic compounds were identified, with gallic acid and quercetin being predominant, above 49.84 and 37.27 μg/g DW, respectively. The mineral analysis revealed zinc and iron as the major constituents. Regarding the plants’ antioxidant and antibacterial activity, both Astragalus species had antioxidant potential, and their water extracts showed antibacterial activity against S. aureus and E. coli. Altogether, these results provide insight into the potential of A. glycyphyllos and A. cicer as a source of nutritional benefits and active phytochemicals for many people, and they can be applied in the food sector as foods and as promising sources of natural ingredients.
- Valorisation of pumpkin by-products: Chemical composition and bioactive properties of pumpkin seeds, peels, and fibrous strands from different local landraces of GreecePublication . Leichtweis, Maria G.; Molina, Adriana K.; Dias, Maria Inês; Calhelha, Ricardo C.; Pires, Tânia C.S.P.; Pavli, Ourania; Oliveira, Beatriz; Ferreira, Isabel C.F.R.; Petropoulos, Spyridon A.; Barros, Lillian; Pereira, CarlaThis study evaluated the fruit by-products (peels, seeds, and fibrous strands) from 11 pumpkin genotypes cultivated in Greece aiming to valorize them as natural sources of bioactive compounds. Five compounds, including ( )-epicatechin and chicoric acid isomers, were identified in peels, while seeds and fibrous strands mainly contained ( )-epicatechin. Organic acids and tocopherols varied significantly among genotypes, with oxalic, quinic, and malic acids being predominant. Total tocopherols content (mg/100 g) ranged up to 7.38 ± 0.03 in fibrous strands, 30.7 ± 0.2 in peels, and 14.58 ± 0.09 in seeds. Extracts exhibited potent antioxidant activity, particularly the seeds of genotypes “V5” and “V6”, and strong antimicrobial effects, notably the peels of “V2 T" and “V11”, which showed significant inhibition of microbial strains. These findings contribute to the advancement of sustainable practices in the agro-industrial waste management, as well as to the production of functional natural ingredients for various industrial applications