Browsing by Author "Tzortzakis, Nikolaos"
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- Bioactive compounds content and antimicrobial activities of wild edible Asteraceae species of the Mediterranean flora under commercial cultivation conditionsPublication . Petropoulos, Spyridon Α.; Fernandes, Ângela; Tzortzakis, Nikolaos; Soković, Marina; Ćirić, Ana; Barros, Lillian; Ferreira, Isabel C.F.R.Nine wild edible species belonging to Astreaceae family, native to the Mediterranean basin were tested for their chemical composition (phenolic compounds, tocopherols, and organic acids) and antimicrobial activities over two growing periods, apart from Scolymus hispanicus and Hedypnois cretica which were tested for only one growing period. Flavonoids were the most abundant phenolic compounds in all the species, except for the case of Taraxacum species where significant amounts of chicoric acid were detected, while phenolic compounds content increased in the 2nd growing period by 4.6–397.4% for the tested species. α- and β-tocopherols were the main tocopherols, apart from Taraxacum sp. where significant amounts of γ-and δ-tocopherols (18.32 and 16.31 μg/ 100 g fresh weight) were detected, while total tocopherols content either increased (Reicardia picroides, Picris echioides, Urospermum picroides, and Taraxacum officinale) or decreased (Hymenonema graecum, Sonchus oleraceus, Taraxacum sp.) in the 2nd growing period. Oxalic acid was the most abundant organic acid, with the highest content (972 mg/100 g fresh weight) being observed in H. graecum (L.) DC. in the 1st growing period. Moreover, with the exception of H. graecum and S. olearaceus, total organic acids content increased in the 2nd growing period. Significant antimicrobial activities were observed against Bacillus cereus, Salmonella typhimurium and Penicillium ochrochloron for all the studied species. In conclusion, the studied species showed great potential for commercial cultivation, while plant extracts could find use in the food industry as alternative food preservatives.
- Chemical and bioactive characterization of Melissa officinalis L. subjected to sustainable cultivation: comparison between different extraction methodsPublication . Oliveira, Izamara; Heleno, Sandrina A.; Carocho, Márcio; Dias, Maria Inês; Santos-Buelga, Celestino; Petropoulos, Spyridon Α.; Tzortzakis, Nikolaos; Chrysargyris, Antonios; Mandim, Filipa; Ferreira, Isabel C.F.R.; Barros, LillianMelissa officinalis L. (lemon balm) is a species of the Lamiaceae family which has been consumed for several decades in the form of decoctions, infusions or directly in food preparations. In addition to its recognized effects in helping digestion problems, rheumatism or headaches, several studies have demonstrated its antioxidant, hypoglycemic, hypolipidemic, antimicrobial, anticancer, antidepressant, anxiolytic, anti-inflammatory, and spasmolytic capacities. In this study it was aimed to compare three different extraction methods: infusion (100% water), maceration (80:20 ethanol: water) and ultrasound assisted extraction (UAE) under previous optimized extraction conditions (33.0 ± 3.2 min, 371.7 ± 19.3 W and 39.9 ± 1.4% ethanol) in plants grown under sustainable cultivation on complete irrigation [1]. The studied parameters included the bioactive evaluation through antimicrobial (microdilution method), antioxidant (thiobarbituric acid reactive substances - TBARS), cytotoxicity (sulforhodamine B) and antiinflammatory (RAW cells) assays. It was also studied the phenolic compounds and organic acids composition. According to the obtained results, eight phenolic compounds were identified and quantified, being rosmarinic acid the major one (107.1 ± 0.9 mg/g of extract). Except for lithospermic acid A isomer II (2.38 ± 0.03 mg/g of extract) and hydoxysalvioanolic acid E (20.7 ± 0.1 mg/g of extract), the infusion revealed the lowest extraction of individual polyphenols, while the maceration recorded the highest extractability. On the other hand, the content of six out of the eight detected polyphenols for the ultrasound-assisted extraction was between the infusion and maceration methods. In terms of antioxidant activity determined through the TBARS assay, the infusions showed the highest activity (1.47 ± 0.05 μg/mL), followed by UAE (2.14 ± 0.03 μg/mL) and maceration (5.79 ± 0.06 μg/mL). The antiinflammatory activity showed the opposite trend, with the maceration showing the strongest potential (114 ± 6 μg/mL), followed by infusion (292 ± 6 μg/mL) and UAE (316 ± 8 μg/mL). The antitumor properties were assessed in 5 cell lines, with the best results being recorded for maceration, except in CaCo2 cells, where infusion showed the best results (48 ± 1 μg/mL). All in all, these natural extracts are interesting ingredients, capable of replacing counterparts of synthetic origin, and may find wide applications in the industrial sector (e.g., food, pharmaceutical and cosmetic companies). Besides, a great potential of using the leaves of M. officinalis to obtain extracts enriched in rosmarinic acid was presented, which may be included in developmental strategies for increased plant production.
- Chemical composition and bioactive properties of purple french bean (Phaseolus vulgaris l.) as affected by water deficit irrigation and biostimulants applicationPublication . Fernandes, Ângela; Figueiredo, Sara Monteiro; Finimundy, Tiane C.; Pinela, José; Tzortzakis, Nikolaos; Ivanov, Marija; Soković, Marina; Ferreira, Isabel C.F.R.; Petropoulos, Spyridon Α.; Barros, LillianBiostimulants are a novel and eco-friendly agronomic tool with practical applications in alleviating negative effects of environmental stressors. The present work studied the effects of three biostimulant products (Nomoren (N), Twin-Antistress (TW), and X-Stress (XS)) under normal irrigation (W+) and water deficit irrigation conditions (W-) on the nutritional, chemical composition and bioactive properties of common bean fresh pods. A variable effect of biostimulants and water deficit irrigation was observed on nutritional value parameters, while fructose and sucrose were the main detected sugars, especially in NW+ and CW-treatments. Oxalic, malic, and citric acid were the main detected organic acids, while γ-and total tocopherol content was the highest in TWW+. (+)-Catechin and (-)-epicatechin were the most abundant phenolic compounds, especially in the NW-treatment. A variable antioxidant capacity was observed for the Thiobarbituric Acid Reactive Substances (TBARS) and Oxidative Haemolysis assays (OxHLIA), while TWW+ extracts showed the best overall results against the tested fungi. In conclusion, the tested biostimulants had a positive effect on chemical composition and bioactivities of purple bean depending on the irrigation regime.
- Chemical composition and plant growth of Centaurea raphanina subsp. mixta plants cultivated under saline conditionsPublication . Petropoulos, Spyridon Α.; Fernandes, Ângela; Dias, Maria Inês; Pereira, Carla; Calhelha, Ricardo C.; Chrysargyris, Antonios; Tzortzakis, Nikolaos; Ivanov, Marija; Soković, Marina; Barros, Lillian; Ferreira, Isabel C.F.R.The aim of this report was to study the e ect of salinity (control: 2dS/m, S1: 4 dS/m and S2: 6 dS/m) and harvest time (first harvest on 9 May 2018 and second harvest on 19 April 2018) on the growth and the chemical composition of Centaurea raphanina subsp. mixta plants. The plants of the first harvest were used for the plant growth measurements (fresh weight and moisture content of leaves, rosette diameter, number and thickness of leaves), whereas those of the second harvest were not used for these measurements due to the flowering initiation, which made the leaves unmarketable due to their hard texture. The results of our study showed that C. raphanina subsp. mixta plants can be cultivated under mild salinity (S1 treatment) conditions without severe e ects on plant growth and yield, since a more severe loss (27.5%) was observed for the S2 treatment. In addition, harvest time proved to be a cost-e ective cultivation practice that allows to regulate the quality of the final product, either in edible form (first harvest) or for nutraceutical and pharmaceutical purposes as well as antimicrobial agents in food products. Therefore, the combination of these two agronomic factors showed interesting results in terms of the quality of the final product. In particular, high salinity (S2 treatment) improved the nutritional value by increasing the fat, proteins and carbohydrates contents in the first harvest, as well as the tocopherols and sugars contents (S1 and S2 treatments, respectively) in the second harvest. In addition, salinity and harvest time a ected the oxalic acid content which was the lowest for the S2 treatment at the second harvest. Similarly, the richest fatty acid ( -linolenic acid) increased with increasing salinity at the first harvest. Salinity and harvest time also a ected the antimicrobial properties, especially against Staphylococcus aureus, Bacillus cereus and Trichoderma viride, where the extracts from the S1 and S2 treatments showed high e ectiveness. In contrast, the highest amounts of flavanones (pinocembrin derivatives) were detected in the control treatment (second harvest), which was also reflected to the highest antioxidant activity (TBARS) for the same treatment. In conclusion, C. raphanina subsp. mixta plants seem to be tolerant to medium salinity stress (S1 treatment) since plant growth was not severely impaired, while salinity and harvesting time a ected the nutritional value (fat, proteins, and carbohydrates) and the chemical composition (tocopherols, sugars, oxalic acid, fatty acids), as well as the bioactive properties (cytotoxicity and antimicrobial properties) of the final product.
- Comparison between different extraction methods in the recovery of bioactive molecules from Melissa officinalis L. under sustainable cultivation: chemical and bioactive characterizationPublication . Oliveira, Izamara; Heleno, Sandrina A.; Carocho, Márcio; Alves, Maria José; Vaz, Josiana A.; Dias, Maria Inês; Buelga, Celestino S.; Petropoulos, Spyridon Α.; Tzortzakis, Nikolaos; Chrysargyris, Antonios; Ferreira, Isabel C.F.R.; Barros, LillianMelissa officinalis L., from the Lamiaceae family, is one of the most important medicinal and aromatic plants with potential in the market. With the passing of time, the use of medicinal plants in the treatment of some illness has gone from the simplest forms of local treatment to the industrial manufacture of phytotherapics. In addition to their medicinal effect, they can also be used in the form of infusions and decoctions and in various food preparations. In this sense, the objective of this work was to compare three different extraction methods: infusion (100% water), maceration (80:20 ethanol: water v:v) and ultrasound-assisted extraction (UAE) under previous optimized extraction conditions (33.0 +- 3.2 min, 371.7 +- 19.3Wand 39.9 +- 1.4% ethanol), in plants grown under sustainable cultivation under full irrigation in June. The parameters studied included bioactive evaluation by antioxidant (thiobarbituric acid reactive substances—TBARS), cytotoxicity (sulforhodamine B) and anti-inflammatory (RAWcells) assays. The composition of phenolic compounds and organic acids was also studied by GC-MS and HPLC-DAD, respectively. According to the obtained results, eight phenolic compounds were identified and quantified, being rosmarinic acid the main one for the three extraction methods (infusion: 107.1 +- 0.9 mg/g extract; maceration: 155.7 +- 0.3 mg/g extract; UAE: 118.7 0.6 mg/g extract). For Lithospermic acid A isomer (25.25 +- 0.01 mg/g) and Hydroxylsalvianolic E (111.70 +- 2.20 mg/g), the UAE revealed the lowest content of individual polyphenols, whereas maceration recorded the highest extractability. On the other hand, the content of six of the eight polyphenols detected for the ultrasound-assisted extraction was similar to the infusion and maceration methods. In terms of antioxidant activity, the infusions showed the highest capacity (3.00 +- 0.14 +-g/mL), followed by maceration (5.33 +- 0.30 +-g/mL) and UAE (12 +- 0.15 +-g/mL). The highest anti-inflammatory activity was verified for the infusion (244 +- 11 +-g/mL), followed by UAE (305 +- 9 +-g/mL), with no activity recorded for the maceration extract (>400 +-g/mL). The antitumor properties were evaluated in five cell lines, with the best results being recorded for infusion, except AGS (24 +- 1 +-g/mL) where
- Edible flowers as an emerging horticultural product: a review on sensorial properties, mineral and aroma profilePublication . Pires Junior, Eleomar de O.; Di Gioia, Francesco; Rouphael, Youssef; García-Caparrós, Pedro; Tzortzakis, Nikolaos; Ferreira, Isabel C.F.R.; Barros, Lillian; Petropoulos, Spyridon Α.; Caleja, CristinaBackground: The current consumer needs for functional and healthy foods, as well as for diversified diets that include a variety of food sources have created a market niche for novel horticultural products such as edible flowers and related food formulations. Scope and approach: Considering the increasing interest on this crop production sector during the last few years, this review aims to compile the most relevant data regarding the production and marketing aspects of edible flowers, focusing on pre-and postharvest parameters that should be taken into account to facilitate their suc-cessful marketing. Moreover, this review presents the most important flower species that have been traditionally used or suggested for edible uses, while the sensorial attributes and the mineral profile of edible flowers are also presented. A special section is dedicated to the aroma components and the essential oils of several flower species focusing on those reports which refer to species with edible uses, while the bioactivities of these compounds are also cited. Finally, future remarks regarding the next steps that are required for the establishment of this new food segment in the market and the consumer awareness for related products are discussed. Key findings and conclusions: Edible flowers is a promising and challenging horticultural crop which could provide alternative solutions to farmers under the ongoing climate changing, having also in mind the sustainable use of natural resources, the diversification of agroecosystems and the preservation of biodiversity. Moreover, food industry could benefit by covering market demands for functional and healthy foods through the development of novel floral-based foods and food formulations, thus allowing the valorization of species that are unexplored or underexplored so far.
- Effect of phosphorus application rate on Mentha spicata L. grown in deep flow technique (DFT)Publication . Chrysargyris, Antonios; Petropoulos, Spyridon Α.; Fernandes, Ângela; Barros, Lillian; Tzortzakis, Nikolaos; Ferreira, Isabel C.F.R.The present study evaluated the impact of phosphorus application rate on plant growth and physiological parameters, antioxidant activity, chemical composition, and essential oil yield and composition of hydroponically grown spearmint plants. Increased P levels resulted in high dry matter content of the aerial part. Antioxidant activity of spearmint leaves was significantly higher at the highest P levels. Although essential oil yield was not affected, essential oil composition varied among the studied P levels, especially carvone content. Total and individual organic acids content was higher when 50 mg/L P were added in the nutrient solution. Rosmarinic acid was the main detected phenolic compound, while the highest total phenolic compounds and rosmarinic acid content was observed at 50 and 70 mg/L of P, respectively. In conclusion, phosphorus application rate may affect spearmint growth and development, as well as chemical composition and essential oil composition.
- Effects of the extraction techniques on the chemical composition and bioactive properties of lemon balm (Melissa officinalis L.) plants grown under different cropping and irrigation regimesPublication . Oliveira, Izamara; Chrysargyris, Antonios; Heleno, Sandrina A.; Carocho, Márcio; Calhelha, Ricardo C.; Dias, Maria Inês; Petrović, Jovana; Soković, Marina; Petropoulos, Spyridon Α.; Santos-Buelga, Celestino; Tzortzakis, Nikolaos; Barros, LillianThe present study aims to determine the combined effect of cropping system and irrigation regime on the chemical composition and bioactive properties of lemon balm aerial parts. For this purpose, lemon balm plants were grown under two farming systems (conventional farming vs organic farming) and two irrigation levels (full irrigation vs deficit irrigation) and harvested twice throughout the growing period. The collected aerial parts were subjected to three different methods of extractions, namely infusion, maceration and ultrasound-assisted extraction and the obtained extracts were evaluated in terms of chemical profile and bioactivities. Five organic acids with varied composition among the tested treatments were identified in all the tested samples for both harvests, namely, citric, malic, oxalic, shikimic and quinic acid. Regarding phenolic compounds composition, the most abundant ones were rosmarinic acid, lithospermic acid A isomer I and hydroxylsalvianolic E, especially for the maceration and infusion extraction methods. Full irrigation resulted in lower EC50 values than deficit irrigation only in the treatments of the second harvest, while variable cytotoxic and anti-inflammatory effects were recorded in both harvests. Finally, in most cases the lemon balm extracts has similar or better activity than the positive controls, while the antifungal activity of lemon balm extracts was stronger than the antibacterial effects. In conclusion, the results of the present study showed that the implemented agronomic practices, as well as the extraction protocol may significantly affect the chemical profile and bioactivities of lemon balm extracts, suggesting that both the farming system and the irrigation schedule may improve the quality of the extracts depending on the implemented extraction protocol.
- Magnesium and manganese induced changes on chemical, nutritional, antioxidant and antimicrobial properties of the pansy and Viola edible flowersPublication . Oliveira, Izamara; Chrysargyris, Antonios; Finimundy, Tiane C.; Carocho, Márcio; Santos-Buelga, Celestino; Calhelha, Ricardo C.; Tzortzakis, Nikolaos; Barros, Lillian; Heleno, Sandrina A.composition was determined using standard methods. Free sugars, fatty acids, organic acids, tocopherols, and phenolic compounds were analyzed using various HPLC and GC devises. The extract’s antimicrobial, antioxidant, cytotoxicity, and anti-inflammatory activity were assessed. The results indicated that Mg enrichment negatively affected plant growth and mineral accumulation but improved photosynthetic performance. The edible flowers contained significant amounts of protein, low levels of fat, and varying sugar contents, such as glucose and fructose. Various fatty acids and phenolic compounds were identified, with different concentrations depending on the treatment. The flowers exhibited antioxidant potential, antimicrobial activity, cytotoxic effects, and antiinflammatory properties. The correlations between the investigated parameters not only expand knowledge on Mg and Mn interaction but also catalyze significant advancements in sustainable agriculture and food health, fostering a healthier and more conscious future.
- Nutritional profile, phytonutrient composition and biocidal properties of Portulaca oleracea L. regarding the ammonium to total nitrogen ratios in hydroponicsPublication . Paschoalinotto, Beatriz H.; Chrysargyris, Antonios; Añibarro-Ortega, Mikel; Pires, Tânia C.S.P.; Mandim, Filipa; Dias, Maria Inês; Tzortzakis, Nikolaos; Barros, LillianThe contribution of the ammonium: total nitrogen ratio (Nr0.01-0.15) in the nutrient solution on chemical profile and bioactive characteristics of Portulaca oleracea, investigated. Increased Nr levels resulted in increased proteins, total fats, carbohydrates and oxalic acid in leaves and stems, but decreased yield. The only detected tocopherol isoforms were alpha- and beta-tocopherol, with the former to reveal increased values at Nr0.10. The most abundant sugars found were fructose, glucose, sucrose, and trehalose, while total sugars were positively affected by the increased Nr in stems. The higher Nr ratio had a favourable effect on the fatty acid profile, while Oleracein A was the main phenolic component detected in higher levels at Nr0.05 (leaves) and Nr0.10 (stems). The increased Nr levels increased antimicrobial activity, while antioxidant activity was varied in different Nr levels. The Nr ratio for P. oleracea may stimulate health-promoting components, while reducing antinutrients content, hence improving overall product quality.