Person: Rosales Conrado, Noelia
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First Name
Noelia
Last Name
Rosales Conrado
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
19 results
Search Results
Now showing 1 - 10 of 19
Item A combined analytical-chemometric approach for the in vitro determination of polyphenol bioaccessibility by simulated gastrointestinal digestion(Analytical and Bioanalytical Chemistry, 2022) Gómez Mejía, Esther; Rosales Conrado, Noelia; León González, María Eugenia; Valverde de la Fuente, Alejandro; Madrid Albarrán, YolandaIn this study, an integrated characterisation through polyphenol and cafeine content and antioxidant activity was combined with chemometric analysis to assess the efects of simulated in vitro gastrointestinal digestion on the bioaccessibility of these bioactive compounds from nine diferent tea infusions. Tea infusions were characterised based on total favonoids, total polyphenols and antioxidant activity, together with the determination of individual polyphenol content. Fourteen phenolic compounds, including phenolic acids, stilbenes and favonoids, were selected based on their reported bioactivity and high accessibility, attributed to their low molecular weight. Both polyphenols and cafeine were initially monitored in raw tea infusions and through the diferent digestion stages (salivary, gastric and duodenal) by capillary high performance liquid chromatography coupled to diode array detection (cHPLC-DAD) and/or HPLC coupled to a triple quadrupole mass analyser (HPLC–MS/MS). Multivariate analysis of the studied bioactives, using principal component analysis and cluster analysis, revealed that the decafeination process seems to increase the stability and concentration of the compounds evaluated during digestion. The greatest transformations occurred mainly in the gastric and duodenal stages, where low bioactivity indices (IVBA) were shown for resveratrol and cafeic acid (IVBA=0%). In contrast, the polyphenols gallic acid, chlorogenic acid and quercetin gave rise to their availability in white, green and oolong infusion teas (IVBA>90%). Furthermore, highly fermented black and pu-erh varieties could be designated as less bioaccessible environments in the duodenum with respect to the tested compounds.Item 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 DeAlzheimer’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.Item 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 YolandaObtaining 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.Item Screening the extraction process of phenolic compounds from pressed grape seed residue: Towards an integrated and sustainable management of viticultural waste(LWT - Food Science and Technology, 2022) Gómez Mejía, Esther; Vicente Zurdo, David; Rosales Conrado, Noelia; León González, María Eugenia; Madrid Albarrán, YolandaThe integrated valorisation of waste from the food chain to obtain value-added compounds with biological functionality will facilitate the transition to the era of a sustainable bioeconomy. To this end, an efficient matrix solid-phase dispersion (MSPD) extraction method was developed and optimized, using experimental factorial design and response surface methodology, for polyphenols recovery from pressed grape seeds obtained after the extraction of essential oils by cold pressing. Gallic, dihydroxybenzoic, p-coumaric and trans-ferulic acid, naringin, resveratrol, quercetin and kaempferol were quantified at 2.1–295 μg g−1 by capillary liquid chromatography coupled to a diode array detector and a mass analyser (cLC-DAD-MS). Furthermore, total antioxidant activity, free radical scavenging and lipid peroxidation suppression, together with the inhibition of beta-amyloid (Αβ42) protein aggregation, considered one of the main pathological effects of Alzheimer's disease, were evaluated. Potent lipid peroxidation inhibition (IC50 0.238 ± 0.003 ng g−1) was observed, along with the reduction of Αβ42 fibril width (9.4–54.8%) and aggregation. The results presented proved that the MSPD extraction method could be considered as an efficient and sustainable methodology to produce phenolic-rich extracts that may serve as an alternative antioxidant and neuroprotective ingredient for the food or pharmaceutical formulations, leading to the cascade valorisation of winery by-products.Item 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, RubénThe 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.Item 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, FatihaEthnopharmacological 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).Item 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; SpringerDue 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.Item Valorisation of black mulberry and grape seeds: Chemical characterization and bioactive potential(Food Chemistry, 2021) Gómez Mejía, Esther; Lobo Roriz, Custódio ; Heleno, Sandrina ; Calhelha, Ricardo ; Dias, Maria Inês ; Pinela, José; Rosales Conrado, Noelia; León González, María Eugenia De; Ferreira, Isabel; Barros, LillianGrape (Vitis vinifera L. var. Albariño) and mulberry (Morus nigra L.) seeds pomace were characterized in terms of tocopherols, organic acids, phenolic compounds and bioactive properties. Higher contents of tocopherols (28 ± 1 mg/100 g fw) were obtained in mulberry, whilst grape seeds were richer in organic acids (79 ± 4 mg/100 g fw). The phenolic analysis of hydroethanolic extracts characterised grape seeds by catechin oligomers (36.0 ± 0.3 mg/g) and mulberry seeds by ellagic acid derivatives (3.14 ± 0.02 mg/g). Both exhibited high antimicrobial activity against multiresistant Staphylococcus aureus MIC = 5 mg/mL) and no cytotoxicity against carcinogenic and non-tumour primary liver (PLP) cells. Mulberry seeds revealed the strongest inhibition (p < 0.05) against thiobarbituric reactive substances (IC50 = 23 ± 2 µg/mL) and oxidative haemolysis (IC50 at 60 min = 46.0 ± 0.8 µg/mL). Both seed by-products could be exploited for the developing of antioxidant-rich ingredients with health benefits for industrial application.Item A combined approach based on matrix solid-phase dispersion extraction assisted by titanium dioxide nanoparticles and liquid chromatography to determine polyphenols from grape residues(Journal of Chromotography A, 2021) Gómez Mejía, Esther; Hartwig Mikkelsen, Line; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda; ElsevierA simple and efficient low-cost matrix solid phase dispersion (MSPD) extraction assisted by TiO2 nanopar- ticles and diatomaceous earth has been developed for the extraction of phenolic compounds from grape and grape pomace wastes. Experimental conditions for MSPD extraction were optimized by a facto- rial design and a surface response methodology. The simultaneous identification and quantification of eight main natural polyphenols (caffeic, p-coumaric, dihydroxybenzoic and gallic acid, rutin, resveratrol, quercetin and catechin) was possible by combining MSPD and capillary liquid chromatography coupled to a diode array detection and a mass simple quadrupole analyzer (cLC-DAD-MS). Good linearity and acceptable LOD (0.05–62 μg· g −1 ) and LOQ (0.2–207 μg· g −1 ) were obtained. The quantities of extracted polyphenols were within 2.4 and 333 μg· g −1, with catechin and rutin the most abundant compounds in rape pomace and grape wastes, respectively. Furthermore, considering the prospective uses of the win- ery bioresidues, the extracts have been characterised in terms of bioactive properties (several antioxidant activities and bacterial inhibition against Staphylococcus aureus, Escherichia coli and Pseudomona aerugi- nosa) and parameters such as total polyphenol and total flavonoid content. The high antioxidant activity (IC 50 5.0 ± 0.4 μg ·g −1 against DPPH radical) and antibacterial activity (2.2 ± 0.3 mg· mL −1 ) suggests that the methodology developed is efficient, rapid and promising for the extraction of phenolic compounds with potential application as bioactive ingredients in food and cosmetic industries.Item Residual brewing yeast as a source of polyphenols: Extraction, identification and quantification by chromatographic and chemometric tools(Food Chemistry, 2018) León González, María Eugenia De; Gómez Mejía, Esther; Rosales Conrado, Noelia; Madrid Albarrán, María YolandaA method combining aqueous extraction, reversed-phase high-performance capillary liquid chromatography with photodiode array detection (cLC-DAD) and chemometric tools, was developed to determine phenolic compounds in residual brewing yeast. The effect of temperature, nature of extraction solvent and method for separation of extract solution were studied to optimize the extraction conditions on the basis of total phenolic content (TPC), total flavonoids content (TFC) and antioxidant capacity. Polyphenols were determined by cLC-DAD. Flavonols as rutin and kaempferol, flavonoids as naringin, phenolic acids as gallic acid and antioxidants as trans-ferulic and p-coumaric acids were found and quantified in the brewing residue. Data were subjected to evaluation using multifactor ANOVA and principal component analysis (PCA), both showing that lyophilization pretreatment affects the content of individual polyphenols and that residual brewing yeast contains higher polyphenol amounts than the liquid beer waste. The obtained results suggest that residual brewing yeast could be a source of polyphenols.