Person:
Gómez Mejía, Esther

First Name

Esther

Last Name

Gómez Mejía

URI

https://hdl.handle.net/20.500.14352/86234

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Químicas

Department

Química Analítica

Identifiers

Full item page

Search Results

Now showing 1 - 10 of 17

Determination of phenolic compounds in residual brewing yeast using matrix solid-phase dispersion extraction assisted by titanium dioxide nanoparticles
(Journal of Chromatography A, 2019) Gómez Mejía, Esther; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda; ELSEVIER
A simple and efficient low-cost matrix solid-phase dispersion (MSPD) extraction based on TiO2nanopar-ticles (NPs) and diatomaceous earth has been developed for the recovery of phenolic compounds fromresidual brewing yeast. Experimental conditions for MSPD extraction were optimized by an experimen-tal design approach. A screening factorial design plus replicates at the center point, followed by surfaceresponse analysis were used. The simultaneous identification and quantification of eleven main nat-ural polyphenols: caffeic, chlorogenic, p-coumaric, 3,4-dihydroxibenzoic, trans-ferulic and gallic acids,kaempferol, myricetin, naringin, quercetin and rutin, was possible by combining MSPD and capillaryliquid chromatography couple to a diode array detection system (cLC-DAD) and liquid chromatogra-phy couple to a triple quadrupole analyzer (LC–MS/MS). Moreover, residual brewing yeast extracts wereevaluated in terms of DPPH (1,1-diphenyl–2 picrylhydrazyl) free radical scavenging activity. Polyphenol-nanoparticle interaction was studied by UV–vis spectroscopy and electron transmission microscopy(TEM), pointing out a stable interplay that assists phenolic isolation. The extracted polyphenol quan-tities were within the 3.2-1,500 g g−1range, and the high antioxidant activity estimated suggested thatdeveloped MSPD is a successful, simple, efficient and rapid method for the extraction and recovery of bioactive phenolic compounds, which promotes the reuse and re-evaluation of brewing yeast agri-foodby-products.
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.
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.
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.
A Comprehensive Analytical Review of Polyphenols: Evaluating Neuroprotection in Alzheimer’s Disease
(International Journal of Molecular Sciences, 2024) Vicente Zurdo, David; Gómez Mejía, Esther; Rosales Conrado, Noelia; León González, María Eugenia De
Alzheimer’s Disease (AD), a prevalent neurodegenerative disorder, is the primary cause of dementia. Despite significant advancements in neuroscience, a definitive cure or treatment for this debilitating disease remains elusive. A notable characteristic of AD is oxidative stress, which has been identified as a potential therapeutic target. Polyphenols, secondary metabolites of plant origin, have attracted attention due to their potent antioxidant properties. Epidemiological studies suggest a correlation between the consumption of polyphenol-rich foods and the prevention of chronic diseases, including neurodegenerative disorders, which underscores the potential of polyphenols as a therapeutic strategy in AD management. Hence, this comprehensive review focuses on the diverse roles of polyphenols in AD, with a particular emphasis on neuroprotective potential. Scopus, ScienceDirect, and Google Scholar were used as leading databases for study selection, from 2018 to late March 2024. Analytical chemistry serves as a crucial tool for characterizing polyphenols, with a nuanced exploration of their extraction methods from various sources, often employing chemometric techniques for a holistic interpretation of the advances in this field. Moreover, this review examines current in vitro and in vivo research, aiming to enhance the understanding of polyphenols’ role in AD, and providing valuable insights for forthcoming approaches in this context.
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.
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.
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.
Anti-inflammatory activity of ethyl acetate and n-butanol extracts from Ranunculus macrophyllus Desf. and their phenolic profile
(Journal of Ethnopharmacology, 2021) Deghima, Amirouche ; Righi, Nadjat; Rosales Conrado, Noelia; León González, María Eugenia De; Baali, Faiza; Gómez Mejía, Esther; Madrid Albarrán, María Yolanda; Bedjou, Fatiha
Ethnopharmacological relevance: The members of the genus Ranunculus have counter-irritating properties and thus, they are traditionally used for treating anti-inflammatory disorders and other skin conditions. Ranunculus macrophyllus Desf. is a wild medicinal plant growing in Algeria and traditionally used to treat some cutaneous skin disorders. Aim: The aim of this study was to characterize the composition of the ethyl acetate and n-butanol extracts from Ranunculus macrophyllus Desf. as well as to elucidate and to compare their effect against acute skin inflammation. Moreover, both the antioxidant activity and the acute toxicity of the plant extracts were also studied. Materials and methods: Spectrophotometric and chromatographic methods were employed to identify and quantify phenolic compounds and triterpenoids from R. macrophyllus Desf. fractions. The antioxidant activity was estimated using the phosphomolebdenum, DPPH, reducing power and β-carotene bleaching assays. The ethyl acetate and n-butanol extracts were screened for their anti-inflammatory activities using ex-vivo membrane stabilizing assays and in-vivo acute skin inflammation model. Results: Ethyl acetate fraction showed the highest amounts of total phenolic compounds (413 ± 4 μg GAE/mg extract) and triterpenoids (70.4 ± 1.8 μg UAE/mg extract). Rutin, hesperidin, myricetin and kaempferol were the major compounds identified in the different fractions. Ethyl acetate fraction exhibited strong DPPH• radical scavenging ability (IC50 1.6 ± 0.2 μg/mL), high total antioxidant capacity (447 ± 7 μg AAE/mg extract) and reducing power (514 ± 8 μg AAE/mg extract). Ethyl acetate fraction inhibited (73.4 ± 0.3) % of linoleic acid peroxidation. Ethyl acetate and n-butanol fractions did not have any visible toxicity at 2000 mg/kg and presented excellent membrane stabilizing ability. The inhibition of xylene induced ear inflammation was (38 ± 4) % and (46 ± 1) % for RM-B and RM-EA, respectively. Conclusions: The high content of both phenolic compounds and triterpenoids combined with the remarkable antiinflammatory effect and antioxidant activity of ethyl acetate and n-butanol extracts from R. macrophyllus Desf. support the wide spread use of this traditional plant on some skin disorders (inflammatory skin disorders).
Valorisation of the green waste parts from large-leaved buttercup (Ranunculus macrophyllus Desf.): phenolic profile and health promoting effects study
(Waste and biomass valorization, 2020) Deghima, Amirouche; Righi, Nadjat; Rosales Conrado, Noelia; León González, María Eugenia De; Baali, Faiza; Gómez Mejía, Esther; Madrid Albarrán, María Yolanda; Bedjou, Fatiha; Springer
Due to the extensive use of Ranunculus macrophyllus Desf. roots for medicinal purposes, most of the leafy green parts are just wasted. The aim of this work is to valorize the leafy green parts and promote their application in different modern industries. Methods For this purpose, we studied the phenolic profile of R. macrophyllus Desf. (RM-B) using chromatographic and spectrophotometric methods and we tested the in-vitro antioxidant activity and the in-vivo effect of RM-B on plasma and liver antioxidant statuts. Results RM-B contained high amounts of polyphenols (675 mg GAE/100 g dry weigh dw) and flavonoids (105 mg QE/100 g dw). In-vitro, RM-B exhibited promising radical scavenging activity against 2,2′-azino-bis(3-éthylbenzothiazoline-6-sulphonique) (ABTS+·) (IC50: 247 µg/mL), hydrogen peroxide radicals (IC50: 626 µg/mL) and inhibited oxidative red blood cells hemolysis (IC50: 120 µg/mL), RM-B also showed strong reducing power (982 µM FeSO4/mg extract). In-vivo, RM-B improved the radical scavenging ability and reducing power of plasma and enhanced liver antioxidant status by increasing catalase and reduced glutathione levels and decreasing malondialdhyde levels without altering the key serum biochemical parameters reflecting liver and kidney functions. Polyphenols identified using capillary LC-DAD and LC–MS/MS analyses like hesperidin (131.2 mg/100 g dw), rutin (29.0 mg/100 g dw) and p-coumaric acid (5.8 mg/100 g dw), may be responsible for the health promoting effects of RM-B. Conclusion We may conclude that R. macrophyllus Desf. is a good source of beneficial polyphenols with strong antioxidant, anti-hemolytic and health-promoting effects, which promotes its use in pharmaceutical, medicinal and nutraceutical industries.