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- Potential of Portuguese vine shoot wastes as natural resources of bioactive compoundsPublication . Moreira, Manuela M.; Barroso, M. Fátima; Porto, João Vasconcellos; Ramalhosa, Maria João; Švarc-Gajić, Jaroslava; Estevinho, Letícia; Morais, Simone; Delerue-Matos, CristinaSince annually a high amount of wastes is produced in vine pruning, the aim of this study was to evaluate the potential of vine shoots from two Portuguese grape varieties (Touriga Nacional - TN and Tinta Roriz - TR) to be used as a natural source of phenolic compounds. To reach this goal, three techniques were explored, namely microwave-assisted extraction (MAE), subcritical water extraction (SWE) and conventional extraction (CE). The phenolic composition of the extracts, antioxidant and biological activities were evaluated by spectrophotometry and chromatography. MAE and SWE produced the highest concentrated extracts. TR vine shoot variety had the highest antioxidant activity and total phenolic (32.1±0.9mggallicacidequivalents/g dry sample), as well as flavonoid content (18.7±1.2mgepicatechinequivalents/g dry sample). For the first time, the biological activity of the vine shoot extracts was tested. Results demonstrated that all of them had antimicrobial potential against different bacteria and yeasts, and the ability of inhibiting α-amylase and acetylcholinesterase enzymes, with MAE TR extracts being the most efficient. HPLC analysis enabled the identification of different phenolic compounds, with gallic acid, catechin, myricetin and kaempferol-3-O-rutinoside being the main contributors to the phenolic composition. Portuguese vine shoot wastes could serve as easily accessible source of natural antioxidants for the food or pharmaceutical industries.
- A multivariate approach based on physicochemical parameters and biological potential for the botanical and geographical discrimination of Brazilian bee pollenPublication . De-Melo, Adriane Alexandre Machado; Estevinho, Leticia M.; Moreira, Manuela M.; Delerue-Matos, Cristina; Freitas, Alex da Silva de; Barth, Ortrud Monika; Almeida-Muradian, Ligia Bicudo de
- Evaluation of the adsorption potential of biochars prepared from forest and agri-food wastes for the removal of fluoxetinePublication . Fernandes, Maria João; Moreira, Manuela M.; Paíga, Paula; Dias, Diogo; Bernardo, Maria; Carvalho, Maria Manuela; Lapa, Nuno; Fonseca, Isabel; Morais, Simone; Figueiredo, Sónia; Delerue-Matos, CristinaTwelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15 min in all systems. The maximum adsorption capacity obtained was 6.41 mg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).
- Evaluation of the impact of pre-treatment and extraction conditions on the polyphenolic profile and antioxidant activity of Belgium apple woodPublication . Withouck, Hannes; Boeykens, Annick; Vanden Broucke, Machteld; Moreira, Manuela M.; Delerue-Matos, Cristina; De Cooman, LucThis study describes the possibilities of valorising a waste stream that originates from apple wood by mapping the reducing capacity and phenolic profile from extracts derived from apple tree (Malus domestica). This study evaluated the efficiency of warm solvent extraction (WSE) and ultrasound-assisted extraction (UAE) techniques for extracting antioxidant phenolic compounds from the bark and core wood of an apple tree cultivated in the north-eastern part of Belgium. Furthermore, the influence of the pre-treatment technique, namely, fresh, oven-dried, and freeze-dried samples, respectively, on the yield of polyphenols was studied. Fresh bark extract obtained by UAE—the most efficient extraction technique—employing acetone 60% v/v contains the highest levels of phenolic compounds as well as the highest antioxidant activity. High-performance liquid chromatographic analysis shows that phloridzin is the major compound of the identified polyphenol markers present in bark and core wood extracts. Based on the obtained results, it may be possible to produce a polyphenolic extract from apple wood at an industrial scale without extensive costs or altering the antioxidant properties. This study reveals the potential of apple tree wood residues valorisation through the recovery of phenolic compounds for food, pharmaceutical, and cosmetic applications.
- New insights of phytochemical profile and in vitro antioxidant and neuroprotective activities from optimized extract of Horned Melon fruitPublication . Vieira, Elsa F.; Podlasiak, Martyna; Moreira, Manuela M.; Grosso, Clara; Rodrigues, Francisca; Fernandes, Virgínia Cruz; Delerue-Matos, CristinaThis study aimed the optimization of antioxidant activity, total phenolic compounds (TPC) and total carotenoids of Horned Melon fruit submitted to maceration extraction, using ethanol as solvent. Optimization was performed by Box–Behnken design on three levels and three variables: extraction temperature (25 °C, 55 °C, and 85 °C), extraction time (0.5, 2.0, and 3.5 h) and ethanol concentration (10%, 50%, and 90%). The optimal conditions to improve the carotenoids extraction was 55 °C, 1.5 h and 86% ethanol, whereas the antiradical/antioxidant activity (ABTS and FRAP assays) and TPC were enhanced at 45 °C for 2.0 h and 40% ethanol. The optimal antioxidant extract was characterized regarding the phenolic composition and in vitro neuroprotective activities. The phenolic composition revealed the presence of high amounts of gallic acid (11.7 ± 0.6 mg/100 g dw) and protocatechuic acid (7.69 ± 0.38 mg/100 g dw). However, this extract presented a weak activity against Monoamine oxidase A (11.8 ± 2.3% inhibition at 2.7 mg/mL) and did not display anti-cholinesterase activity at the maximum concentration tested (1.3 mg/mL). Maceration was an efficient extraction technique to recover polyphenols and carotenoids from Horned Melon fruit. The optimized model can be very useful for food and pharmaceutical industries
- Subcritical water extraction of antioxidants from mountain germander (Teucrium montanum L.)Publication . Nastić, Nataša; Švarc-Gajić, Jaroslava; Delerue-Matos, Cristina; Morais, Simone; Barroso, M. Fátima; Moreira, Manuela M.In the present work, antioxidant compounds from Teucrium montanum were extracted by subcritical water. The influence of extraction temperature and pressure on antioxidant activity of extracts has been investigated in terms of extraction yield (EY), total phenolic content (TPC), and DPPH-radical scavenging activity (DPPH-RSA) and ferric reducing antioxidant power (FRAP). Additionally, the compounds responsible for the antioxidant activity were identified and quantified by high performance liquid chromatography (HPLC). The highest EY (42.63%), TPC (174.61 ± 4.09 mg GAE/g DE) and antioxidant activity by DPPH-RSA (176.23 ± 8.76 mg TE/g DE) and FRAP (141.71 ± 5.21 mg AAE/g DE) were seen in extracts obtained at temperature of 160 °C and pressure of 10 bar. HPLC analysis revealed that naringin and gallic acid were the principle antioxidant compounds in subcritical extracts. According to the results, SWE has a great potential in exploitation of natural sources of bioactive compounds and production of pharmacologically-active fractions.
- Electro-Fenton degradation of a ternary pharmaceutical mixture and its application in the regeneration of spent biocharPublication . Puga, Antón; Moreira, Manuela M.; Figueiredo, Sónia A.; Delerue-Matos, Cristina; Pazos, Marta; Rosales, Emilio; Sanromán, M. ÁngelesThis study proposed an integrated valorisation system, by combining adsorption and electro-Fenton processes for fast and effective micropollutant remediation of a complex pharmaceutical mixture. The pharmaceuticals venlafaxine, fluoxetine and trazodone, commonly detected in the environment (river water and sediment), were selected in this study as target pollutants. Initially, the electro-Fenton degradation process of the ternary mixture was optimised. For this, a Box-Behnken experimental design was used and the degradation of each pollutant, as a response function, was evaluated using three key operational process parameters (iron concentration, current intensity and solution pH). The pharmaceutical mixture was removed by total adsorption onto the biochar, the regeneration of which was then carried out under the optimal electro-Fenton conditions (0.24 mA, 0.33 mM Fe2+ and pH 3.2). In addition, different options in relation to the presence of iron were considered: i) iron dissolved in aqueous solution; ii) iron supported on the biochar; iii) no addition of iron (“self-cleaning”). The results confirmed that the natural content of iron in the biochar was enough to catalyse the electro-Fenton regeneration. The adsorption-electro-Fenton regeneration process was repeated over several cycles with no reduction in the efficiency of either process. Finally, this combination (adsorption and electro-Fenton process) was tested using an aqueous matrix from a wastewater treatment plant.
- Evaluation of the Extraction Temperature Influence on Polyphenolic Profiles of Vine-Canes (Vitis vinifera) Subcritical Water ExtractsPublication . Dorosh, Olena; M. Moreira, Manuela; Pinto, Diana; F. Peixoto, Andreia; Freire, Cristina; Costa, Paulo; Rodrigues, Francisca; Delerue-Matos, CristinaThis work focused on evaluating the possibility of using vineyard pruning wastes from two Portuguese Vitis vinifera varieties; Touriga Nacional (TN) and Tinta Roriz (TR), as new potential ingredients for the nutraceutical industry. An environmentally friendly extraction technique; namely subcritical-water extraction (SWE), was employed. The overall results indicate that phenolic acids were the major class of compounds quantified; being gallic acid the principal one. The highest value for total phenolic content (TPC) was obtained for the TR extract at 250 °C (181 ± 12 mg GAE/g dw). In terms of antioxidant activity; the DPPH values for the extracts obtained at 250 °C were approximately 4-fold higher than the ones obtained at 125 °C; with TR extract presenting the highest value (203 ± 22 mg TE/g dw). Thus, the TR extract obtained through SWE at 250 °C was selected to evaluate the scavenging activity and the in vitro effects on cells due to the best results achieved in the previous assays. This extract presented the ability to scavenge reactive oxygen species (O2●-, HOCl and ROO●). No adverse effects were observed in HFF-1 viability after exposure to extract concentrations below 100 μg/mL. This work demonstrated that vine-canes extracts could be a potential ingredient to nutraceutical industry
- Vine-Canes as a Source of Value-Added Compounds for Cosmetic FormulationsPublication . Moreira, Manuela M.; Rodrigues, Francisca; Dorosh, Olena; Pinto, Diana; Costa, Paulo C.; Švarc-Gajić, Jaroslava; Delerue-Matos, CristinaThe majority of works about vine-canes are focused on the evaluation of their chemical composition and antioxidant potential. To the best of our knowledge, the possible applications of produced extracts in cosmetic formulations have never been explored. The aim of the present study was to evaluate the antioxidant properties of vine-canes subcritical water extracts for use as active ingredients in the cosmetic industry. For that, the phenolic content and antioxidant activity of six vine-cane varieties, namely Alvarinho and Loureiro from the Minho region and Touriga Nacional and Tinta Roriz (TR) from both the Douro and Dão regions, were evaluated through spectrophotometric and chromatographic methods. All extracts presented similar antioxidant activity and the highest phenolic content was reported for TR variety from the Douro region (33.7 ± 1.9 mg GAE/g dw). The capacity of vine-cane extracts to capture reactive oxygen species superoxide (O2∙−) was also studied, with the highest IC50 value being obtained for Loureiro variety (56.68 ± 2.60 µg/mL). Furthermore, no adverse effects on HaCaT and HFF-1 dermal cell lines in concentrations below 100 and 1000 μg/mL, respectively, were determined. Finally, Loureiro vine-cane extract was incorporated into a topical formulation, and physical and microbiological properties were within expected values, demonstrating that vine-canes extracts can be successfully incorporated in cosmetic products.
- Removal of diclofenac and sulfamethoxazole from aqueous solutions and wastewaters using a three-dimensional electrochemical processPublication . Soares, Cristina; Correia-Sá, Luísa; Paíga, Paula; Barbosa, Carlos; Remor, Paula Verônica; Freitas, Olga; Moreira, Manuela M.; Nouws, Henri; Correia, Manuela; Ghanbari, Amir; Rodrigues, António J.; Oliveira, Carlos M.; Figueiredo, Sónia; Delerue-Matos, CristinaThe three-dimensional (3D) electrochemical treatment process was studied for the removal of two pharmaceuticals, diclofenac (anti-inflammatory) and sulfamethoxazole (antibiotic), in mono and bi-component systems. Adsorption and conventional two-dimensional electrochemical processes were initially studied and then combined to develop the 3D process. The influence of different operating parameters on the removal efficiency was studied: the distance between the cathode and the anode, the pharmaceutical and electrolyte (NaCl) concentrations, the pH, and the (carbon-based) adsorbent used as particulate electrode (biochar and commercial activated carbon, granulometry, and amount). The energy consumption and the electric energy per order were evaluated. The results demonstrate the efficiency of the 3D process for the removal of diclofenac and sulfamethoxazole from aqueous solutions, both for mono- and bi-component systems, achieving their complete removal respectively in 10 and 30 min, using a Mixed Metal Oxide anode (titanium-coated with RuO2-IrO2-TiO2), a stainless steel cathode, a biochar particulate electrode (1–2 mm), an initial pharmaceutical concentration of 10 mg/L, an inter-electrode distance of 7.5 cm, a pH value of 7 and a current density of 7 mA/cm2. The optimised 3D process was also successfully applied to a wastewater treatment plant effluent, but lower removal efficiencies were observed (after 30 min) for bi-component fortified samples; 49% for DCF and 86% for SMX, with energy consumptions of 1224 and 613 Wh/g and an electric energy per order of 19.1 and 8.77 kWh/m3 respectively. On the other hand, the pharmaceuticals were completely removed from the effluent when real concentrations (i.e. without their addition) were used
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