Person:
Rosales Conrado, Noelia

First Name

Noelia

Last Name

Rosales Conrado

URI

https://hdl.handle.net/20.500.14352/76222

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Químicas

Department

Química Analítica

Area

Química Analítica

Identifiers

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Now showing 1 - 10 of 26

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 Yolanda
A 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.
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; Elsevier
A 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.
Ability of selenium species to inhibit metal-induced Aβ aggregation involved in the development of Alzheimer’s disease
(Analytical and Bioanalytical Chemistry, 2020) Vicente Zurdo, David; Romero Sánchez, Iván; Rosales Conrado, Noelia; León González, María Eugenia De; Madrid Albarrán, María Yolanda; Springer Heidelberg
Extracellular accumulation of amyloid beta peptide (Aβ) is believed to be one of the main factors responsible for neurodegeneration in Alzheimer’s disease (AD). Metals could induce Aβ aggregation, by their redox activity or binding properties to amyloid β fibrils, leading to their accumulation and deposition outside neurons. For this reason, metal chelation may have an acknowledged part to play in AD prevention and treatment. In the current work, the role of different selenium species, including selenium nanoparticles, in Aβ aggregation, was studied by evaluating their metal-chelating properties and their ability both to inhibit metal-induced Aβ1–42 aggregation fibrils and to disaggregate them once formed. Transition biometals such as Fe(II), Cu(II), and Zn(II) at 50 μM were selected to establish the in vitro models. The DPPH assay was used to determine the antioxidant capacity of the evaluated selenium species. Selenium nanoparticles stabilized with chitosan (Ch-SeNPs) and with both chitosan and chlorogenic acid polyphenol (CGA@ChSeNPs) showed the highest antioxidant properties with EC50 of 0.9 and 0.07 mM, respectively. UV–Vis and d1(UV–Vis) spectra also revealed that selenium species, in particular selenomethionine (SeMet), were able to interact with metals. Regarding Aβ1–42 incubation experiments, Fe(II), Cu(II), and Zn(II) induced Aβ aggregation, in a similar way to most of the evaluated selenium species. However, Ch-SeNPs produced a high inhibition of metal-induced Aβ aggregation, as well as a high disaggregation capacity of Aβ fibrils in both the presence and absence of biometals, in addition to reducing the length and width (20% of reduction in the presence of Zn(II)) of the generated Aβ fibrils.
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, Lillian
Grape (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.
Project number: 81
Página web del grupo bilingüe de la Facultad de Educación para la enseñanza de las ciencias: elaboración, explotación y juicio crítico de los estudiantes de cara a la internacionalización de la docencia
(2017) Peña Martínez, Juan; Sánchez Gómez, Pedro; Rosales Conrado, Noelia; Fresno Galán, María; Acebrón Hernández, Ainhoa; Merino Catalina, Beatriz; Cabezas Martínez, Sara; Meléndez Pérez, Celia; Martínez Arevalo, Victoria; Lazaro Sánchez, Paula
Elaboración de una página web con material didáctico de Ciencias para el grupo bilingüe de Educación, que además sirve para ofrecer información para estudiantes que pudieran estar interesados en formar parte del grupo, incluyendo estudiantes extranjeros.
Learning Principal Component Analysis by Using Data from Air Quality Networks
(Journal of Chemical Education, 2017) Pérez Arribas, Luis Vicente; León González, María Eugenia De; Rosales Conrado, Noelia
With the final objective of using computational and chemometrics tools in the chemistry studies, this paper shows the methodology and interpretation of the Principal Component Analysis (PCA) using pollution data from different cities. This paper describes how students can obtain data on air quality and process such data for additional information related to the pollution sources, climate effects, and social aspects over pollution levels by using a powerful chemometrics tool such as principal component analysis (PCA). The paper could also be useful for students interested in environmental chemistry and pollution interpretation; this statistical method is a simple way to display visually as much as possible of the total variation of the data in a few dimensions, and it is an excellent tool for looking into the normal pollution patterns.
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
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.
Extraction of polyphenols and synthesis of new activated carbon from spent coffee grounds
(Scientific Reports, 2019) Ramón-Gonçalves, Marina; Alcaraz, Lorena; Pérez-Ferreras, Susana; León González, María Eugenia De; Rosales Conrado, Noelia; López, Félix ; Nature Research
A valorization process of spent coffee grounds (SCG) was studied. Thus, a two-stage process, the first stage of polyphenols extraction and synthesis of a carbonaceous precursor and a subsequent stage of obtaining activated carbon (AC) by means of a carbonization process from the precursor of the previous stage, was performed. The extraction was carried out with a hydro-alcoholic solution in a pressure reactor, modifying time, temperature and different mixtures EtOH:H2O. To optimize the polyphenols extraction, a two-level factorial experimental design with three replicates at the central point was used. The best results were obtained by using a temperature of 80 °C during 30 min with a mixture of EtOH:H2O 50:50 (v/v). Caffeine and chlorogenic acid were the most abundant compounds in the analysed extracts, ranging from 0.09 to 4.8 mg∙g−1 and 0.06 to 9.7 mg∙g−1, respectively. Similarly, an experimental design was realized in order to analyze the influence of different variables in the AC obtained process (reaction time, temperature and KOH:precursor ratio). The best results were 1 h, 850 °C, and a mixture of 2.5:1. The obtained activated carbons exhibit a great specific surface (between 1600 m2∙g−1 and 2330 m2∙g−1) with a microporous surface. Finally, the adsorption capacity of the activated carbons was evaluated by methylene blue adsorption.
Neuroprotective Action of Multitarget 7-Aminophenanthridin-6(5H)-one Derivatives against Metal-Induced Cell Death and Oxidative Stress in SN56 Cells
(ACS Chemical Neuroscience, 2021) Moyano-Cires Ivanoff, Paula Viviana; Vicente Zurdo, David; Blázquez-Barbadillo, Cristina; Menéndez Ramos, José Carlos; González Matilla, Juan Francisco; Rosales Conrado, Noelia; Pino Sans, Javier Del
Neurodegenerative diseases have been associated with brain metal accumulation, which produces oxidative stress (OS), matrix metalloproteinases (MMPs) induction, and neuronal cell death. Several metals have been reported to downregulate both the nuclear factor erythroid 2-related factor 2 (Nrf2) pathway and the antioxidant enzymes regulated by it, mediating OS induction and neurodegeneration. Among a recently discovered family of multitarget 7-amino-phenanthridin-6-one derivatives (APH) the most promising compounds were tested against metal-induced cell death and OS in SN56 cells. These compounds, designed to have chelating activity, are known to inhibit some MMPs and to present antioxidant and neuroprotective effects against hydrogen peroxide treatment to SN56 neuronal cells. However, the mechanisms that mediate this protective effect are not fully understood. The obtained results show that compounds APH1, APH2, APH3, APH4, and APH5 were only able to chelate iron and copper ions among all metals studied and that APH3, APH4, and APH5 were also able to chelate mercury ion. However, none of them was able to chelate zinc, cadmium, and aluminum, thus exhibiting selective chelating activity that can be partly responsible for their neuroprotective action. Otherwise, our results indicate that their antioxidant effect is mediated through induction of the Nrf2 pathway that leads to overexpression of antioxidant enzymes. Finally, these compounds exhibited neuroprotective effects, reversing partially or completely the cytotoxic effects induced by the metals studied depending on the compound used. APH4 was the most effective and safe compound.
Project number: 47
Integración de los enfoques AICLE y CTIM en las actividades experimentales del grupo bilingüe de la Facultad de Educación
(2019) Peña Martínez, Juan; Rosales Conrado, Noelia; Sánchez Gómez, Pedro; García Núñez, Iván; Herrero Ojalvo, Ignacio Gilberto
En el presente proyecto se han rediseñado las prácticas de Física del grupo bilingüe para que los estudiantes apliquen el doble enfoque Ciencia-Tecnología-Ingeniería-Matemáticas (CTIM) y Aprendizaje Integrado de Ciencias en Lengua Extranjera (AICLE). Asimismo, se ha recabado su valoración para futuros trabajos.