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- Thymus lotocephalus wild plants and in vitro cultures produce different profiles of phenolic compounds with antioxidant activityPublication . Costa, Patrícia; Gonçalves, Sandra; Valentão, Patrícia; Andrade, Paula B.; Coelho, Natacha; Romano, AnabelaWe compared the phenolic metabolites and antioxidant activities of Thymus lotocephalus G. López & R.Morales wild plants and in vitro cultures using different extraction solvents. HPLC–DAD analysis allowed the identification and quantification of phenolic (caffeic and rosmarinic) acids and flavones (luteolin and apigenin) in extracts from both sources. The in vitro cultures accumulated large amounts of rosmarinic acid. However, extracts from both sources were able to neutralise free radicals in different test systems(TEAC and ORAC assays), to form complexes with Fe2+ and to protect mouse brains against Fe2+-induced lipid peroxidation. The solvent significantly influenced the phenolic content and antioxidant activity of the extracts, water/ethanol being the most efficient for the extraction of antioxidant phytochemicals. We conclude that in vitro cultures of T. lotocephalus represent a promising alternative for the production of valuable natural antioxidants and an efficient tool for the in vitro biosynthesis of rosmarinic acid, therefore avoiding the need to exploit populations of wild plants.
- Protective effects of Lavandula viridis L'Hér extracts and rosmarinic acid against H2O2-induced oxidative damage in A172 human astrocyte cell linePublication . Costa, Patrícia; Sarmento, Bruno; Gonçalves, Sandra; Romano, AnabelaWe investigated the neuroprotective effect of Lavandula viridis extracts (infusion, water:ethanol and methanol) and rosmarinic acid, the major compound present in the extracts, against oxidative damage induced by hydrogen peroxide (H2O2) in A172 human astrocyte cell line regarding the neurotoxic effect, intracellular reactive oxygen species (ROS) production and the activity of the antioxidant enzyme catalase (CAT). We found that L. viridis extracts and rosmarinic acid protected A172 astrocytes against H2O2 and reduced intracellular ROS accumulation. Furthermore, the protection effect was not caused by modulation of CAT suggesting that other intracellular mechanisms are involved in the neuroprotective effect. Our results highlight that L. viridis extracts and rosmarinic acid have beneficial effects against oxidative damage associated with neurodegenerative diseases. © 2013.
- Influence of wine pH and ethanol content on the fining efficacy of proteins from winemaking by-productsPublication . Baca-Bocanegra, Berta; Gonçalves, Sandra; Nogales-Bueno, Julio; Mansinhos, Inês; Heredia, Francisco José; Hernández-Hierro, José Miguel; Romano, A.Wine color and limpidity are important aspects of consumer preferences. The alteration of these parameters can damage wine’s appearance but also its mouthfeel characteristics due to its relationship with attributes such as bitterness and astringency. Fining is a practice usually used in enology to modulate undesirable wine organoleptic attributes. However, there are several factors that influence this technique. In this study, the influence of wine pH and ethanol content on grape seed protein fining efficacy has been assessed. Wine clarification, total phenolic and flavanol contents, antioxidant activity, and chromatic parameters have been investigated before and after fining process. The most noticeable clarifying effects were observed for the experimental wines with a lower pH and ethanol content. Control of these factors will make it possible to modulate the main organoleptic properties of the wine, also avoiding the addition of large amounts of fining agents and thus providing greater versatility to wineries during winemaking. Furthermore, our findings indicated that grape seed protein is a potential alternative to other plant-based fining proteins commonly used in winemaking. Its effects on clarification and color quality have been found to be comparable to those of potato protein and significantly better than those of pea protein.
- Ultrasonic-assisted extraction and natural deep eutectic solvents combination: A green strategy to improve the recovery of phenolic compounds from Lavandula Pedunculata subsp. Lusitanica (Chaytor) FrancoPublication . Mansinhos, Inês; Gonçalves, Sandra; Rodríguez Solana, Raquel; Ordóñez-Díaz, José Luis; Moreno-Rojas, José Manuel; Romano, A.The present study aimed at evaluating the effectiveness of different natural deep eutectic solvents (NADES) on the extraction of phenolic compounds from Lavandula pedunculata subsp. lusitanica (Chaytor) Franco, on the antioxidant activity, and acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (Tyr) inhibitory capacities. Ten different NADES were used in this research and compared with conventional solvents. Ultrasound-assisted extraction (UAE) for 60 min proved to be the best extraction condition, and proline:lactic acid (1:1) and choline chloride:urea (1:2) extracts showed the highest total phenolic contents (56.00 ± 0.77 mgGAE/gdw) and antioxidant activity [64.35 ± 1.74 mgTE/gdw and 72.13 ± 0.97 mgTE/gdw in 2.2-diphenyl-1- picrylhydrazyl (DPPH) and 2.20 -azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) methods, respectively]. These extracts also exhibited enzymes inhibitory capacity particularly against Tyr and AChE. Even so, organic acid-based NADES showed to be the best extractants producing extracts with considerable ability to inhibit enzymes. Twenty-four phenolic compounds were identified by HPLC-HRMS, being rosmarinic acid, ferulic acid and salvianolic acid B the major compounds. The results confirmed that the combination of UAE and NADES provide an excellent alternative to organic solvents for sustainable and green extraction, and have huge potential for use in industrial applications involving the extraction of bioactive compounds from plants.
- Accumulation of phenolic compounds in in vitro cultures and wild plants of Lavandula viridis L'Her and their antioxidant and anti-cholinesterase potentialPublication . Costa, Patrícia; Gonçalves, Sandra; Valentão, Patrícia; Andrade, Paula B.; Romano, AnabelaIn this study, we evaluated the phenolic profile, antioxidant and anti-cholinesterase potential of different extracts from wild plants and in vitro cultures of Lavandula viridis L'Her. The HPLC-DAD analysis allowed the identification and quantification of 3-0-caffeoylquinic, 4-0-caffeoylquinic, 5-0-caffeoylquinic and rosmarinic acids, and luteolin and pinocembrin. Water/ethanol extract from in vitro cultures contained the highest amount of the identified phenolic compounds (51652.92 mg/kg). To investigate the antioxidant activity we used Trolox equivalent antioxidant capacity, oxygen radical absorbance capacity, Fe2+ chelation activity and the inhibition of Fe2+-induced lipid peroxidation in mouse brain homogenates (in vitro). Overall, all the extracts from both wild plants and in vitro cultures exhibited ability to scavenge free radicals, to chelate Fe2+ and to protect against lipid peroxidation. In addition, the extracts from L. viridis were active in inhibiting both acetylcholinesterase and butyrylcholinesterase (Ellman's method). Our findings suggest that L. viridis in vitro cultures represent a promising alternative for the production of active metabolites with antioxidant and anti-cholinesterase activity. (C) 2013 Elsevier Ltd. All rights reserved.
- How climate change-related abiotic factors affect the production of industrial valuable compounds in lamiaceae plant species: a reviewPublication . Paixão Mansinhos, Inês Filipa; Gonçalves, Sandra; Romano, AnabelaThe interest in medicinal and aromatic plants (MAPs) has increased significantly in recent years, driven by the growing demand for natural products. MAPs are a valuable source of secondary metabolites, which renders them useful to a number of industries, including cosmetics, pharmaceuticals, and food. The Lamiaceae family includes economically important MAPs that produce valuable secondary metabolites such as essential oils (EOs) and phenolic compounds (PCs). The quantity and quality of these secondary metabolites are affected by abiotic stress factors. In a climate change scenario, the Lamiaceae is one of the most affected families, especially due to its wide distribution in the Mediterranean region. In the present study, the most common climate-related environmental stress factors, namely, drought, salinity, temperature, light, and heavy metals, were reviewed and discussed in order to assess their impact on the chemical profiles of EOs and PCs, as well as on the biological properties (antioxidant, antibacterial, antimelanogenic, pest-repellent, and UV-protective) of Lamiaceae species. It can be posited that these stresses typically act as a catalyst for the secondary metabolism of these plants, resulting in increased production of EO compounds (e.g., 1,8-cineole, linalool, camphor, borneol, and limonene) and PCs (e.g., rosmarinic, caffeic, and salvianolic acids) and subsequent enhancement of their biological activities. In view of the industrial applications of these bioactive compounds, it is of interest to explore the changes in secondary metabolism induced by environmental factors as it is possible to increase the accumulation of valuable secondary metabolites.
- Phytochemical characterization and bioactivity of extracts from different fruit parts of opuntia leucotricha DC.: a comparison between a conventional organic solvent and green natural deep eutectic solventsPublication . Hamdoun, Ouafaa; Gonçalves, Sandra; Paixão Mansinhos, Inês Filipa; Rodríguez Solana, Raquel; Pereira-Caro, Gema; Moreno-Rojas, José Manuel; El Kbiach, Mohammed L’bachir; El Bouzdoudi, Brahim; Romano, AnabelaThe objective of this study was to analyze the chemical profile of extracts from different fruit parts of the perennial arborescent cactus Opuntia leucotricha by applying ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) and to evaluate their biological properties (antioxidant and enzyme inhibitory capacities). Extracts were obtained from the fruit pulp (without or with seeds), seeds, and peel by ultrasound-assisted extraction (UAE) using the conventional solvent methanol 50% and two Natural Deep Eutectic Solvents (NADESs) (glycerol:urea, 1:1 and citric acid:sorbitol, 1:2). A total of 33 compounds were identified, including phenolics, fatty acids, and others. Phenolic acids were the most abundant class of phenolics identified in all fruit parts, with the highest concentration observed in the methanol extracts from peel (593.02 mu g/gDW), followed by seed-containing pulp (69.03 mu g/gDW), pulp (57.83 mu g/gDW), and seeds (39.97 mu g/gDW). The second most effective extractant was NADES 1 (glycerol:urea, 1:1), which was also successful in extracting compounds with antioxidant capacity. Overall, the extracts demonstrated considerable enzyme inhibitory activities, with the greatest effects observed against alpha-amylase and alpha-glucosidase. The results indicate that O. leucotricha fruits could be a promising source of bioactive compounds, and NADES a viable alternative to organic solvents for their industrial exploitation.
- Nutrient deficiency-induced stress improves skincare effects and phytochemical content of green extracts from lamiaceae in vitro culturesPublication . Paixão Mansinhos, Inês Filipa; Gonçalves, Sandra; Rodríguez Solana, Raquel; Pereira-Caro, Gema; Moreno-Rojas, José; Romano, AnabelaThe objective of this study was to investigate the impact of nutrient starvation on the growth, biochemical, metabolomic, and biological traits of Lavandula viridis L'H & eacute;r and Thymus lotocephalus G. L & oacute;pez and R. Morales in vitro cultures. In both species, a reduction in shoot growth and in the production of chlorophyll and carotenoids was observed in cultures grown under nutrient-deficient media (especially Fe and N) compared to those grown under control conditions. The highest levels of hydrogen peroxide and lipid peroxidation, two indicators of oxidative stress, were observed in L. viridis cultures grown under N deficiency and in T. lotocephalus under P and Fe limitation. The results demonstrated that nutrient deficiency led to a 72% and 62% increase in the quantified phenolic compounds in L. viridis and T. lotocephalus, respectively. The highest concentrations of the major compound in both species-rosmarinic acid-were observed in cultures grown under Mg-deficient (60.7 +/- 1.0 mg/gDW) and Fe-deficient (50.0 +/- 0.4 mg/gDW) conditions in L. viridis and T. lotocephalus, respectively. Furthermore, nutrient starvation enhanced the capacity of green extracts to inhibit three enzymes (tyrosinase, elastase, and hyaluronidase) associated with anti-aging and their antioxidant properties.