Person:
León González, María Eugenia De

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First Name
María Eugenia De
Last Name
León González
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
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Now showing 1 - 10 of 19
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    Unravelling the in vitro and in vivo potential of selenium nanoparticles in Alzheimer’s disease: A bioanalytical review
    (Talanta, 2023) Vicente Zurdo, David; Rosales Conrado, Noelia; León González, María Eugenia De
    Alzheimer’s disease (AD) is a devastating neurodegenerative disorder characterized by progressive cognitive decline and the accumulation of beta-amyloid plaques and tau tangles in the brain. Current therapies have limited efficacy, prompting the search for novel treatments. Selenium nanoparticles (SeNPs) have emerged as promising candidates for AD therapy due to their unique physicochemical properties and potential therapeutic effects. This review provides an overview of SeNPs and their potential application in AD treatment, as well as the main bioanalytical techniques applied in this field. SeNPs possess antioxidant and anti-inflammatory properties, making them potential candidates to combat the oxidative stress and neuroinflammation associated with AD. Moreover, SeNPs have shown the ability to cross the blood-brain barrier (BBB), allowing them to target brain regions affected by AD pathology. Various methods for synthesizing SeNPs are explored, including chemical,physical and biological synthesis approaches. Based on the employment of algae, yeast, fungi, and plants, green methods offer a promising and biocompatible alternative for SeNPs production. In vitro studies have demonstrated the potential of SeNPs in reducing beta-amyloid aggregation and inhibiting tau hyperphosphorylation, providing evidence of their neuroprotective effects on neuronal cells. In vivo studies using transgenic mousem models and AD-induced symptoms have shown promising results, with SeNPs treatment leading to cognitive improvements and reduced amyloid plaque burden in the hippocampus. Looking ahead, future trends in SeNPs research involve developing innovative brain delivery strategies to enhance their therapeutic potential, exploring alternative animal models to complement traditional mouse studies, and investigating multi-targeted SeNPs formulations to address multiple aspects of AD pathology. Overall, SeNPs represent a promising avenue for AD treatment, and further research in this field may pave the way for effective and much-needed therapeutic interventions for individuals affected by this debilitating disease.
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    Valorization of prunus seed oils: fatty acids composition and oxidative stability
    (Molecules, 2023) Rodríguez-Blázquez, Sandra; Gómez Mejía, Esther; Rosales Conrado, Noelia; León González, María Eugenia De; García-Sánchez, Beatriz; Miranda Carreño, Rubén
    Prunus fruit seeds are one of the main types of agri-food waste generated worldwide during the processing of fruits to produce jams, juices and preserves. To valorize this by-product, the aim of this work was the nutritional analysis of peach, apricot, plum and cherry seeds using the official AOAC methods, together with the extraction and characterization of the lipid profile of seed oils using GC-FID, as well as the measurement of the antioxidant activity and oxidative stability using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging method. Chemometric tools were required for data evaluation and the obtained results indicated that the main component of seeds were oils (30–38%, w). All seed oils were rich in oleic (C18:1n9c) and linoleic (C18:2n6c) acids and presented heart-healthy lipid indexes. Oil antioxidant activity was estimated in the range IC50 = 20–35 mg·mL−1, and high oxidative stability was observed for all evaluated oils during 1–22 storage days, with the plum seed oil being the most antioxidant and stable over time. Oxidative stability was also positively correlated with oleic acid content and negatively correlated with linoleic acid content. Therefore, this research showed that the four Prunus seed oils present interesting healthy characteristics for their use and potential application in the cosmetic and nutraceutical industries.
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    Insights into the accumulation and transformation of Ch-SeNPs by Raphanus sativus and Brassica juncea: effect on essential elements uptake
    (Science of the Total Environment, 2020) Moreno Martín, Gustavo; Sanz Landaluce, Jon; León González, María Eugenia De; Madrid Albarrán, María Yolanda; Elsevier
    Selenium (Se) at very low doses has important functions for humans. Unfortunately, the low levels of Se in soils in various regions of the world have implemented the agronomic biofortification of crops by applying Se-enriched fertilizers (mainly based on selenate). Lately, the use of nanofertilizers is growing in interest as their low size reduces the amount of chemicals and minimizes nutrient losses in comparison with conventional bulk fertilizers. However, the knowledge on their fate and environmental impact is still scarce. This study aims to evaluate the biotransformation of chitosan-modified Se nanoparticles (Ch-SeNPs) as well as their effect on the metabolism of essential metals (Fe, Cu, Zn and Mo) when applied to hydroponic cultivation of R. sativus and B. juncea. In house-synthesized Ch-SeNPs were characterized in both synthesis and hydroponic culture media by transmission electron microscopy (TEM), dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA). The composition of one-tenth strength Hoagland's solution did not affect the size, shape and concentration in number of particles per mL of Ch-SeNPs. The plants were grown inside a box at 25 °C during the months of May–July in 2018. After a week of treatment with Ch-SeNPs, plants were harvested and divided into roots and aerial part. The biotransformation of Ch-SeNPs was evaluated through a process of enzymatic hydrolysis and subsequent analysis by HPLC-ICP-MS and HPLC-ESI-MS/MS. The results confirmed the transformation of Ch-SeNPs to seleno-amino acids: Selenomethionine (SeMet), Semethylselenocysteine (SeMetSeCys) and ɣ-glutamyl-Se-MetSeCys. Moreover, Multiple-way analysis of variance (ANOVA) and principal component analysis (PCA) showed that, regardless the plant species, Ch-SeNPs supplementation affected the absorption of Zn.
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    Characterization of AgNPs and AuNPs in sewage sludge by single particle inductively coupled plasma-mass spectrometry
    (Talanta, 2022) Moreno Martín, Gustavo; Gómez Gómez, Beatriz; León González, María Eugenia De; Madrid Albarrán, María Yolanda; Elsevier
    This study develops for the first time an analytical method for the characterization of silver and gold nanoparticles in sewage sludge. The evaluation of the effect of temperature, extracting agent and centrifugation speed and time on the extraction yield was carried out through a multifactorial analysis of variance which allows us to select 289 g, 5 min and 20 mM sodium pyrophosphate tetrabasic as optimal extraction conditions. Under these conditions, the analysis of the extract by single particle inductively coupled plasma-mass spectrometry provided recovery percentages of 70 ± 2% and 56 ± 1% for silver and gold nanoparticles, respectively. Moreover, the complementary results obtained upon analysis of these extracts by transmission electron microscopy and single particle inductively coupled plasma-mass spectrometry showed that the developed method did not modify the original size and shape of these nanoparticles during the extraction procedure. Size detection limits of 23 nm and 16 nm as well as number concentration limits of 3.12 × 109 particles kg−1 and 1.38 × 109 particles kg−1 were obtained for silver and gold nanoparticles, respectively. Moreover, a stability study of silver and gold nanoparticles in sewage sludge for 12 months showed differences between the two nanoparticle types. Although the sizes were not affected during the 12 months, silver nanoparticles underwent an oxidation process from 6 months onwards, which was reflected in an increase in the percentage of ionic silver from 14 ± 1% at 6 months to 24 ± 2% at 12 months. The developed methodology represents a simple, reliable and fast tool for detecting, quantifying and assessing the stability of nanoparticles in an important environmental sample such as sewage sludge.
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    Valorization of citrus reticulata blanco peels to produce enriched wheat bread: phenolic bioaccessibility and antioxidant potential
    (ANTIOXIDANTS, 2023) Gómez Mejía, Esther; Sacristán, Iván; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda
    The fortification of foods with bioactive polyphenols aims to improve their functional properties and to provide health benefits. Yet, to exert their benefits, phenolic compounds must be released from the food matrix and absorbed by the small intestine after digestion, so assessing their bioaccessibility is crucial to determine their potential role. This work aims to incorporate Citrus reticulata Blanco peel extracts into wheat bread as a promising opportunity to increase their bioactive potential, along with supporting the sustainable management of citrus-industry waste. A control and a wheat bread enriched at 2% and 4% (w/v) with a phenolic extract from mandarin peels were prepared and analyzed for antioxidant activity and phenolic composition using LC-MS and UV-Vis spectrophotometry. In addition, in vitro digestion was performed, and the digested extracts were analyzed with HPLC-MS/MS. The results showed a significant increase in total flavonoid content (TFC, 2.2 ± 0.1 mg·g−1), antioxidant activity (IC50 = 37 ± 4 mg·g−1), and contents of quercetin, caffeic acid, and hesperidin in the 4% (w/v) enriched bread. Yet, most polyphenols were completely degraded after the in vitro digestion process, barring hesperidin (159 ± 36 μg·g−1), highlighting the contribution of citrus enrichment in the development of an enriched bread with antioxidant potential.
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    Phenolic profile, safety, antioxidant and anti-inflammatory activities of wasted Bunium ferulaceum Sm. aerial parts
    (Food Research International, 2022) Deghima, Amirouche; Righi, Nadjat; Rosales Conrado, Noelia; León González, María Eugenia De; Baali, Faiza; Gómez Mejía, Esther; Madrid Albarrán, María Yolanda; Bedjou, Fatiha; ELSEVIER
    The pharmaceutical and nutraceutical industries benefit greatly from recycling and transforming non-utilized parts of medicinal plants from agro-industrial operations into value added products. Hence, the aim of this work was to study the potential nutraceutical and pharmaceutical applications of Bunium ferulaceum Sm. aerial parts, in order to maximize their value. The phenolic profile of their hydromethanolic extract was determined and its antioxidant activity was evaluated in vitro and in vivo alongside with its anti-inflammatory activity and safety profile. The extract exerted an in vitro antioxidant activity mainly through radical scavenging (DPPH IC50: 14.0 ± 0.3 μg/ml) and iron chelating ability (24 ± 2 μg/ml), while, in vivo, the extract did not cause any mortality or visible signs of acute toxicity at high dose (2000 mg/kg body weight). The supplementation of the extract at different doses improved mice liver redox state by increasing catalase and reduced glutathione levels and reducing lipid peroxidation, without causing any toxicity. Moreover, the extract efficiently inhibited xylene induced ear inflammation (62 %). These different bioactivities were linked to the phenolic compounds present in the extract, particularly, chlorogenic acid (78 ± 6 mg/g extract), rutin (44 ± 2 mg/g extract) and hesperidin (56 ± 9 mg/g extract). However, further studies should be carried out on the isolated major compounds found in the extract to correlate the activity with these compounds or their mixture. The wasted aerial parts of Bunium ferulaceum Sm. proved to be a valuable source of polyphenols and exhibited interesting health promoting effects with no toxicity. Thus, Bunium ferulaceum Sm. aerial parts can be included in nutraceutical formulations or used as functional food and the extracted compounds may be used as an alternative food preservative.
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    Effect of Storage and Drying Treatments on Antioxidant Activity and Phenolic Composition of Lemon and Clementine Peel Extracts
    (Molecules, 2023) Gómez Mejía, Esther; Sacristán Navarro, Iván; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda
    Obtaining polyphenols from horticultural waste is an emerging trend that enables the valorization of resources and the recovery of value-added compounds. However, a pivotal point in the exploitation of these natural extracts is the assessment of their chemical stability. Hence, this study evaluates the effect of temperature storage (20 and −20 ◦C) and drying methods on the phenolic composition and antioxidant activity of clementine and lemon peel extracts, applying HPLC-DADMS, spectrophotometric methods, and chemometric tools. Vacuum-drying treatment at 60 ◦C proved to be rather suitable for retaining the highest antioxidant activity and the hesperidin, ferulic, and coumaric contents in clementine peel extracts. Lemon extracts showed an increase in phenolic acids after oven-drying at 40 ◦C, while hesperidin and rutin were sustained better at 60 ◦C. Hydroethanolic extracts stored for 90 days preserved antioxidant activity and showed an increase in the total phenolic and flavonoid contents in lemon peels, unlike in clementine peels. Additionally, more than 50% of the initial concentration was maintained up to 51 days, highlighting a half-life time of 71 days for hesperidin in lemon peels. Temperature was not significant in the preservation of the polyphenols evaluated, except for in rutin and gallic acid, thus, the extracts could be kept at 20 ◦C.
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    Cytotoxicity, uptake and accumulation of selenium nanoparticles and other selenium species in neuroblastoma cell lines related to Alzheimer’s disease by using cytotoxicity assays, TEM and single cell-ICP-MS
    (Analytica Chimica Acta, 2023) Vicente Zurdo, David; Gómez Gómez, Beatriz; Romero Sánchez, Iván; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda; Elsevier B.V.
    Alzheimer’s disease (AD) is the most prevalent neurodegenerative disease, representing 80% of the total dementia cases. The “amyloid cascade hypothesis” stablishes that the aggregation of the beta-amyloid protein (Aβ42) is the first event that subsequently triggers AD development. Selenium nanoparticles stabilized with chitosan (Ch-SeNPs) have demonstrated excellent anti-amyloidogenic properties in previous works, leading to an improvement of AD aetiology. Here, the in vitro effect of selenium species in AD model cell line has been study to obtain a better assessment of their effects in AD treatment. For this purpose, mouse neuroblastoma (Neuro-2a) and human neuroblastoma (SH-SY5Y) cell lines were used. Cytotoxicity of selenium species, such as selenomethionine (SeMet), Se-methylselenocysteine (MeSeCys) and Ch-SeNPs, has been determined by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry methods. Intracellular localisation of Ch-SeNPs, and their pathway through SH-SY5Y cell line, have been evaluated by transmission electron microscopy (TEM). The uptake and accumulation of selenium species by both neuroblastoma cell lines have been quantified at single cell level by single cell- Inductively Coupled Plasma with Mass Spectrometry detection (SCICP-MS), with a previous optimisation of transport efficiency using gold nanoparticles (AuNPs) ((69 ± 3) %) and 2.5 mm calibration beads ((92 ± 8) %). Results showed that Ch-SeNPs would be more readily accumulated by both cell lines than organic species being accumulation ranges between 1.2 and 89.5 fg Se cell􀀀 1 for Neuro-2a and 3.1–129.8 fg Se cell1 for SH-SY5Y exposed to 250 μM Ch-SeNPs. Data obtained were statistically using chemometric tools. These results provide an important insight into the interaction of Ch-SeNPs with neuronal cells, which could support their potential use in AD treatment.
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    Bioactive polyphenols from Ranunculus macrophyllus Desf. Roots: quantification, identification and antioxidant activity
    (South African Journal of Botany, 2020) Deghima, Amirouche; Righi, Nadjat; Rosales Conrado, Noelia; León González, María Eugenia De; Gómez Mejía, Esther; Madrid Albarrán, María Yolanda; Baali, Faiza; Bedjou, Fatiha
    Ranunculus macrophyllus Desf. is an Algerian medicinal plant whose roots are used in traditional medicine to cure feminine infertility and other diseases, however there are no studies regarding its phytochemistry and biological activities. The aim of this work is to study the phytochemical composition and antioxidant activity of different solvents fractions from the roots of Ranunculus macrophyllus Desf. Spectrophotometric and chromatographic methods were used to study the phytochemical composition; while antiradical, iron chelating ability, reducing power and lipid peroxidation were studied in-vitro. The ethyl acetate fraction showed the highest values of total phenolic compounds (271.0 ± 0.2 µg GAE/mg dry extract (d.e), flavonols (24 ± 5 µg RE/ mg d.e) and condensed tannins (129 ± 10 µg CE/mg d.e), while the hexane fraction contained the highest amount of triterpenoids (91 ± 7 µg UAE/mg d.e). The highest radical scavenging ability was recorded for the ethyl acetate fraction against DPPH (IC50 = 3.7 ± 0.1 µg/mL) and ABTS (IC50 = 81 ± 3 µg/mL) whereas the hexane fraction had the best hydrogen peroxide radical scavenging (IC50 = 380 ± 4 µg/mL). The ethyl acetate fraction had the best total antioxidant capacity (TAC = 361 ± 1 µAAE/ mg extract) and reducing power (310 ± 2 µAAE/mg extract). The β-carotene bleaching was inhibited at high rate even after 24 h by the ethyl acetate fraction (81.0 ± 0.5 %). All activities were correlated with the polyphenolic content of the fractions. Capillary LC-DAD and LC-MS/MS analysis of ethyl acetate fraction revealed high amounts of gallic acid (9.3 ± 0.6 mg/g d.e), dihydroxybenzoic acid (8.1 ± 0.2 mg/g d.e) and hesperidin (5.9 ± 0.6 mg/g d.e). With such high amounts of polyphenols and strong antioxidant activity Ranunculus macrophyllus Desf. roots could have a potential use in pharmaceutical and nutraceutical industries.
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    Valorization of defatted cherry seed residues from Liquor processing by matrix solid-phase dispersion extraction: a sustainable strategy for production of phenolic-rich extracts with antioxidant potential
    (Antioxidants, 2023) Rodríguez-Blázquez, Sandra; Fernández-Ávila, Lorena; Gómez Mejía, Esther; Rosales Conrado, Noelia; León González, María Eugenia De; Miranda Carreño, Rubén
    The integrated valorization of food chain waste is one of the most promising alternatives in the transition to a sustainable bioeconomy. Thus, an efficient solid-phase matrix dispersion extraction method, using experimental factorial design and response surface methodology, has been developed and optimized for the recovery of polyphenols from defatted cherry seeds obtained after cherry liquor manufacture and subsequent fatty acid extraction, evaluating the effect of each processing step on the composition and phenolic content of sweet cherry residues. The phenolic extracts before fermentation showed the highest content of total polyphenols (TPC) and flavonoids (TFC) (3 ± 1 mg QE·g−1 and 1.37 ± 0.08 mg GAE·g−1, respectively), while the highest antioxidant capacity was obtained in the defatted seed extracts after both fermentation and distillation. In addition, high-performance liquid chromatography coupled to a quadrupole time-of-flight mass spectrometer (HPLC-ESI-QTOF-MS) was used to determine the phenolic profile. Dihydroxybenzoic acid, neochlorogenic acid, caffeic acid, and quercetin were the main phenolics found, showing differences in concentration between the stages of liquor production. The results underline the prospective of cherry by-products for obtaining phenol-rich bioactive extracts for possible use in different industrial sectors, offering a feasible solution for the cascade valorization of cherry agri-food waste.