María García Nicolás

Dr. María García Nicolás

orcid
PhD in Analytical Chemistry | Juan de la Cierva postdoctoral...

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 September 2020 in Foods
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Journal Article
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MNMaría García Nicolás
María García Nicolás
NANatalia Arroyo-Manzanares
Natalia Arroyo-Manzanares
Lourdes ArceLourdes Arce
Lourdes Arce
MHManuel Hernandez-Cordoba
Manuel Hernandez-Cordoba
PLPilar Viñas López-Pelegrín
Pilar Viñas López-Pelegrín
Due to its multiple advantages, ion mobility spectrometry (IMS) is being considered as a complementary technique to mass spectrometry (MS). The goal of this work is to investigate and compare the capacity of IMS and MS in the classification of olive oil according to its quality. For this purpose, two analytical methods based on headspace gas chromatography (HS-GC) coupled with MS or with IMS have been optimized and characterized for the determination of volatile organic compounds from olive oil samples. Both detectors were compared in terms of sensitivity and selectivity, demonstrating that complementary data were obtained and both detectors have proven to be complementary. MS and IMS showed similar selectivity (10 out of 38 compounds were detected by HS-GC-IMS, whereas twelve compounds were detected by HS-GC-MS). However, IMS presented slightly better sensitivity (Limits of quantification (LOQ) ranged between 0.08 and 0.8 µg g−1 for HS-GC-IMS, and between 0.2 and 2.1 µg g−1 for HS-GC-MS). Finally, the potential of both detectors coupled with HS-GC for classification of olive oil samples depending on its quality was investigated. In this case, similar results were obtained when using both HS-GC-MS and HS-GC-IMS equipment (85.71 % of samples of the external validation set were classified correctly (validation rate)) and, although both techniques were shown to be complementary, data fusion did not improve validation results (80.95% validation rate).

23 March 2023 in Antioxidants
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Journal Article
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MNMaría García Nicolás
María García Nicolás
CLCarlos A Ledesma-Escobar
Carlos A Ledesma-Escobar
FPFELICIANO PRIEGO-CAPOTE
FELICIANO PRIEGO-CAPOTE
Citrus fruits are recommended components of the human diet because of their enriched composition in bioactive compounds and health benefits. Among their notable components are phenols, with a special emphasis on flavonoids, limonoids, and carboxylic acids. In this research, we have carried out a spatial metabolomics analysis for the characterization of these bioactive families in three citrus fruits, namely, lemons, limes, and mandarins. Sampling was undertaken, for which the juices and three fruit tissues, namely, albedo, flavedo, and segments, were analyzed. This characterization allowed for the determination of 49 bioactive compounds in all the samples. The composition of the different extracts was correlated with the antioxidant capacity measured by the DPPH radical scavenging activity and β-carotene bleaching assays. Flavonoids, found in the albedo and flavedo at higher concentrations, were the main components responsible for DPPH radical scavenging activity. On the other hand, the combined action of flavonoids and limonoids contributed to explaining the antioxidant activity measured by the β-carotene bleaching assay. Generally, the antioxidant capacity of juices was lower than that estimated for extracts from citrus tissues.


15 February 2023 in Toxins
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MNMaría García Nicolás
María García Nicolás
NANatalia Arroyo-Manzanares
Natalia Arroyo-Manzanares
PLPilar Viñas López-Pelegrín
Pilar Viñas López-Pelegrín
Dispersive magnetic solid-phase extraction (DMSPE) technique is proposed as a new sensitive and effective sample treatment method for the determination of aflatoxins in paprika samples. DMSPE was followed by ultrahigh-performance liquid chromatography and high-resolution mass spectrometry detection (UHPLC-HRMS) using a non-targeted acquisition mode for the detection of main aflatoxins (aflatoxin G1, G2, B1 and B2) and derivatives. DMSPE was based on the use of magnetic nanocomposite coated with polypyrrole (PPy) polymer and the main experimental parameters influencing the extraction efficiency in adsorption and desorption steps have been studied and optimized. Analyses were performed using 250 µL magnetic PPy nanocomposite into the sample solution, adsorbing the analytes in 30 min and desorbing them with ethyl acetate (2 mL) in 15 min. The method has been validated, obtaining quantification limits between 3.5 and 4.7 µg kg−1 and recoveries between 89.5–97.7%. The high recovery rate, wide detection range and the use for the first time of the reusable Fe3O4@PPy nanomaterial in suspension for solid food matrices, guarantee the usefulness of the method developed for adequate control of aflatoxins levels in paprika. The proposed methodology was applied for the analysis of 31 samples (conventional and organic) revealing the absence of aflatoxins in the samples.

15 November 2025 in Nutrients
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María Paula Jarrín OrozcoMaría Paula Jarrín Orozco
María Paula Jarrín Orozco
MVMaría Romo Vaquero
María Romo Vaquero
CCConcepción Carrascosa
Concepción Carrascosa
MPMiriam Pertegal
Miriam Pertegal
Jose BernaJose Berna
Jose Berna
Juan Carlos EspínJuan Carlos Espín
Juan Carlos Espín
Background/Objectives: Interindividual variability in polyphenol metabolism may help explain the inconsistent effects of polyphenol intake on health outcomes. This study compared, for the first time, (i) polyphenol-related gut microbiota metabotypes (urolithins: UM0, UMA, UMB; equol: EP, ENP; lunularin: LP, LNP) and their clusters (MCs) in non-medicated premenopausal (Pre-M) and postmenopausal (Post-M) women and (ii) the impact of an 8-week intake of a polyphenol-rich plant extract mixture (PPs) on the quality of life (QoL) of Post-M. Methods: Polyphenol metabotypes were determined in urine via UPLC-QTOF-MS after a 3-day intake of PPs containing resveratrol, pomegranate (ellagitannins and ellagic acid), and red clover (isoflavones) in Pre-M (n = 120) and Post-M (n = 90) women. QoL was assessed with the short-form Cervantes Scale in a randomized, placebo-controlled crossover trial (8-week PPs vs. placebo), completed by 78 Post-M participants. Results: At baseline, Pre-M and Post-M women showed only minor differences in metabotype and MC distributions linked to menopausal status. MC3 (UMA+EP+LP) predominated in Pre-M, while MC7 (UMA+EP+LNP) was most frequent in Post-M. PPs intake in Post-M women led to modest shifts in metabotype and MC distributions toward Pre-M patterns. Quantitative metabolite production was comparable between groups, except for equol, which showed a median 2.8-fold increase after PPs intake in EP Post-M women. Clinically meaningful improvements (score reduction ≥ 6.7 points) in QoL were observed in the Psychic domain in EP women (28%, p = 0.039) and in the Menopause and Health domain, specifically in EP (24.1%, p = 0.004), MC3 (22.5%, p = 0.043), and MC4 (UMB+EP+LP; 41.3%, p = 0.022), were mainly driven by a reduction in hot flashes (p = 0.001). Conclusions: These findings support metabotyping as a tool to guide targeted dietary strategies and enhance QoL through precision health in Post-M women.

10 November 2023 in Food and Chemical Toxicology
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Journal Article
Open access
LVLia Visintin
Lia Visintin
MNMaría García Nicolás
María García Nicolás
PVPablo Vangeenderhuysen
Pablo Vangeenderhuysen
TGTess Goessens
Tess Goessens
EAEugenio Alladio
Eugenio Alladio
Marthe De BoevreMarthe De Boevre
Marthe De Boevre
Mycotoxins are secondary metabolites produced by fungi such as Aspergillus, Alternaria, and Penicillium , affecting nearly 80% of global food crops. Tenuazonic acid (TeA) is the major mycotoxin produced by Alternaria alternata, a prevalent pathogen affecting plants, fruits, and vegetables. TeA is notably prevalent in European diets, however, TeA biomarkers of exposure and metabolites remain unknown. This research aims to bridge this knowledge-gap by gaining insights about human TeA exposure and metabolization. Nine subjects were divided into two groups. The first group received a single bolus of TeA at the Threshold of Toxicological Concern (TTC) to investigate the presence of TeA urinary biomarkers, while the second group served as a control. Sixty-nine urinary samples were prepared and analyzed using UPLC-Xevo TQ-XS for TeA quantification and UPLC-Orbitrap Exploris for polar metabolome acquisition. TeA was rapidly excreted during the first 13 h and the fraction extracted was 0.39 ± 0.22. The polar metabolome compounds effectively discriminating the two groups were filtered using Orthogonal Partial Least Squares-Discriminant Analysis and subsequently annotated (n = 122) at confidence level 4. Finally, the urinary metabolome was compared to in silico predicted TeA metabolites. Nine metabolites, including oxidized, N-alkylated, desaturated, glucuronidated, and sulfonated forms of TeA were detected.