Person: Madrid Albarrán, María Yolanda
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First Name
María Yolanda
Last Name
Madrid Albarrán
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
13 results
Search Results
Now showing 1 - 10 of 13
Item 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; ELSEVIERA 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.Item Selenium and tellurium-based nanoparticles as interfering factors in quorum sensing-regulated processes: violacein production and bacterial biofilm formation(Metallomics, 2019) Gómez Gómez, Beatriz; Arregui García-Roves, Lucía; Serrano Barrero, Susana Lourdes; Santos de la Sen, Antonio; Pérez Corona, María Teresa; Madrid Albarrán, María YolandaA cell-to-cell communication system called quorum sensing (QS) promotes the transcription of certain target genes in bacterial cells leading to the activation of different cellular processes, some of them related to bacterial biofilm formation. The formation of bacterial biofilms favours antibiotic resistance, which is nowadays a significant public-health problem. In this study, the effect of selenium (SeNPs) and tellurium (TeNPs) nanoparticles was examined in two bacterial processes mediated by QS: violacein production by Chromobacterium violaceum and biofilm formation by Pseudomonas aeruginosa. For this purpose, quantification of the pigment production in the presence of these nanoparticles was monitored using the C. violaceum strain. Additionally, a combination of different microscopical imaging techniques was applied to examine the changes in the 3D biofilm structure of P. aeruginosa, which were quantified through performing architectural metric calculations (substratum area, cell area coverage and biovolume). SeNPs produce an 80% inhibition in the violacein production by C. violaceum and a significant effect on the P. aeruginosa biofilm architecture (a reduction of 80% in the biovolume of the bacterial biofilm was obtained). TeNPs similarly affect violacein production and the P. aeruginosa biofilm structure but at lower concentration levels. The results obtained suggest an important disruption of the QS signalling system by SeNPs and TeNPs, supporting nanotechnology as a promising tool to fight against the emerging problem of bacterial resistance related to bacterial biofilm formation.Item Simultaneous determination of the size and concentration of AgNPs in water samples by UV–vis spectrophotometry and chemometrics tools(Talanta, 2018) Moreno Martín, Gustavo; León González, María Eugenia De; Madrid Albarrán, María YolandaThe combination of UV–vis spectrophotometry with a chemometric calibration tool based on partial least squares (PLS) has allowed us the development of a multivariate analytical method that simultaneously estimates the concentration and size of mixtures of silver nanoparticles (AgNPs) in environmental water samples. The method is based on changes in the surface plasmon resonance band (SPRB) of AgNPs when they form aggregated/assembled structures with L-cysteine (L-cys). Measurementts were performed by employed a fixed-time kinetics method that implies that the final spectra (response) are obtained by subtstracting the solutions spectra at fixed times. Optimization of experimental conditions affecting aggregation such as time, temperature, pH and concentration of aggregating substance was performed by experimental design and response surface methodologies (RSM). A multivariate calibration model using AgNPs of known diameter size ((20 ± 3), (41 ± 3), (59 ± 5) and (79 ± 7) nm) within a concentration range between 0.62 and 2.5 mg L−1 was constructed by using a mixture experimental design and PLS. The method was finally applied to estimate size and concentration of AgNPs in AgNPs-spiked river and tap water samples. Water samples were spiked with individual, binary and ternary mixtures of AgNPs of different sizes and by using two types of AgNPs: citrate-coated AgNPs (cit-AgNPs) and polyvinylpyrrolidone-coated AgNPs (PVP-AgNPs). A good correspondence was obtained between predicted values and the total amount of AgNPs added with recovery values ranged within 80–160% for the individual mixtures, 68–108% for the binary mixtures and 60–64% for the ternary mixtures of AgNPs. Finally, transmission electron microscopy (TEM) measurements were performed for those cases where discrepancies between the expected and the obtained values were observed. TEM micrographs evidenced the presence of agglomerates or aggregates of AgNPs in some of the mixtures or water tested.Item Determination of size and mass-and number-based concentration of biogenic SeNPs synthesized by lactic acid bacteria by using a multimethod approach(Analytica Chimica Acta, 2017) Moreno Martín, Gustavo; Pescuma, Micaela; Pérez Corona, María Teresa; Mozzi, Fernanda; Madrid Albarrán, María YolandaSelenium nanoparticles (SeNPs) were synthesized by a green technology using lactic acid bacteria (LAB, Lactobacillus acidophilus, L. delbrueckii subsp. bulgaricus and L. reuteri). The exposure of aqueous sodium selenite to LAB led to the synthesis of SeNPs. Characterization of SeNPs by transmission electron microscopy with energy dispersive X-ray spectrum (EDXS) analysis revealed the presence of stable, predominantly monodispersed and spherical SeNPs of an average size of 146 ± 71 nm. Additionally, SeNPs hydrodynamic size was determined by dispersive light scattering (DLS) and nanoparticle tracking analysis (NTA). For this purpose, a methodology based on the use of surfactants in basic medium was developed for isolating SeNPs from the bacterial pellet. The hydrodynamic size values provided by DLS and NTA were 258 ± 4 and 187 ± 56 nm, respectively. NTA measurements of number-based concentration reported values of (4.67±0:30)x 109 SeNPs/mL with a relative standard deviation lower than 5% (n = 3). The quantitative results obtained by NTA were supported by theoretical calculations. Asymmetrical flow field flow fractionation (AF4) on line coupled to the inductively couple plasma mass spectrometry (ICP-MS) and off-line coupled to DLS was further employed to characterize biogenic SeNPs. The distribution of the particle size for the Se-containing peak provide an average size of (247 ± 14) nm. The data obtained by independent techniques were in good agreement and the developed methodologyItem Food prospects of selenium enriched-Lactobacillus acidophilus CRL 636 and Lactobacillus reuteri CRL 1101(Journal of Functional Foods, 2017) Pescuma, Micaela; Gómez Gómez, Beatriz; Pérez Corona, María Teresa; Font, Graciela; Madrid Albarrán, María Yolanda; Mozzi, FernandaSelenium, which is present as SeCys in selenoproteins, is involved in cancer prevention, thyroid functioning, and pathogen inhibition. Lactobacilli can biotransform inorganic Se into seleno-amino acids. Growth, Se accumulation and seleno-amino acid formation by Lactobacillus acidophilus CRL636 and L. reuteri CRL1101 in a Se-supplemented medium were studied. Moreover, survival of Se-enriched strains to different pH values and bile salts was analyzed. L. acidophilus CRL636 showed low growth rate in the presence of Se while differences were less evident for L. reuteri CRL1101, which displayed higher amounts of intracellular SeCys and SeMet than the CRL636 strain. Interestingly, both lactobacilli could produce Se-nanoparticles. Se-enriched lactobacilli showed lower growth rates than non-Se exposed cells. The adverse effect of bile salts and the ability to survive at pH 4.0 diminished for the Se-enriched L. reuteri strain. The studied lactobacilli could be used as Se-enriched probiotics or as a vehicle for manufacturing Se-containing fermented foods.Item Availability of zinc from infant formula by in vitro methods (solubility and dialyzability) and size-exclusion chromatography coupled to inductively coupled plasma-mass spectrometry(Journal of Dairy Sciences, 2016) Gómez Gómez, Beatriz; Pérez Corona, María Teresa; Madrid Albarrán, María YolandaZinc bioaccessibility from infant formula was estimated by in vitro methods (solubility and dialyzability) and size-exclusion chromatography (SEC) coupled to inductively coupled plasma-mass spectrometry (ICP-MS). Infant formula samples were first characterized in terms of Zn bound to lipids and proteins and Zn distribution in the aqueous soluble protein fraction. We found that Zn is not incorporated into the lipid fraction of the samples, being mainly associated with the protein fraction (around 100%). Fractionation of Zn-containing proteins in the soluble protein fraction was achieved by SEC-ICP-MS after performing protein extraction with a solution of 100 mM (pH 6.8) Tris-HCl. The percentages of zinc in the soluble protein fraction in the soy-based and lactose-free infant formula were very low, around 7 and 24%, respectively, whereas the content of Zn in the soluble protein fraction of milk-based formula was around 90%. By SEC-ICP-MS, we found that Zn is associated with low-molecular weight compounds (around 10 kDa) in all the infant formulas tested. The percentages of Zn estimated in the in vitro gastrointestinal digests of the infant formula ranged from 30 to 70% and from 1 to 10% for solubility and dialyzability assays, respectively. The dialyzability test resulted in lower than expected scores, as SEC-ICP-MS analysis of the gastrointestinal extracts revealed that Zn is bound to biomolecules with a molecular weight ranging from 1 to 7 kDa, which suggests that dialysis data should be interpreted with caution. Speciation studies are a valuable tool for establishing availability of nutrients and for validating data from dialyzable in vitro methods.Item Silac-based quantitative proteomic analysis of Lactobacillus reuteri CRL 1101 response to the presence of selenite and selenium nanoparticles(Journal of Proteomics, 2019) Gómez Gómez, Beatriz; Pérez Corona, María Teresa; Mozzi, Fernanda; Pescuma, Micaela; Madrid Albarrán, María YolandaStable isotope labeling in cell culture (SILAC) was applied for the first time on a lactic acid bacterium strain (L. reuteri CRL1101) for analyzing differential protein expression associated to selenite(Na2SeO3) and selenium nanoparticles (SeNPs) exposure. 57 and 47 proteins were found de-regulated by >1,5 fold in presence of selenite and SeNPs, respectively. Only 16 out of 104 proteins differentially expressed were commonly altered by selenite and SeNPs. The use of a clustered heat map allows us to visualize relations between the de-regulated proteins and exposure conditions. We identified a number of proteins involved in diverse functions and biological processes such as metabolism of carbohydrates, selenium and lipids; folding, sorting and degradation; environmental information and processing. In presence of both, selenite and SeNPs, proteins related to selenium metabolism such as cystathione beta-lyase and oxidoreductases (thioredoxine reductase and NAD/FAD oxidoreductase) were over expressed. Interestingly, the over expression of thioredoxin reductase could protect the host from oxidizing compounds. An over expression of phage proteins and chaperones with selenite was observed; this result and the fact that a lower cell count was detected when selenite was added could indicate that this latter Se species has a more deleterious effect than the nanoparticles.Item Simultaneous determination of the size and concentration of AgNPs in water samples by UV–vis spectrophotometry and chemometrics tools(Talanta, 2018) Moreno Martín, Gustavo; León González, María Eugenia De; Madrid Albarrán, María YolandaThe combination of UV–vis spectrophotometry with a chemometric calibration tool based on partial least squares (PLS) has allowed us the development of a multivariate analytical method that simultaneously estimates the concentration and size of mixtures of silver nanoparticles (AgNPs) in environmental water samples. The method is based on changes in the surface plasmon resonance band (SPRB) of AgNPs when they form aggregated/assembled structures with L-cysteine (L-cys). Measurementts were performed by employed a fixed-time kinetics method that implies that the final spectra (response) are obtained by subtstracting the solutions spectra at fixed times. Optimization of experimental conditions affecting aggregation such as time, temperature, pH and concentration of aggregating substance was performed by experimental design and response surface methodologies (RSM). A multivariate calibration model using AgNPs of known diameter size ((20 ± 3), (41 ± 3), (59 ± 5) and (79 ± 7) nm) within a concentration range between 0.62 and 2.5 mg L−1 was constructed by using a mixture experimental design and PLS. The method was finally applied to estimate size and concentration of AgNPs in AgNPs-spiked river and tap water samples. Water samples were spiked with individual, binary and ternary mixtures of AgNPs of different sizes and by using two types of AgNPs: citrate-coated AgNPs (cit-AgNPs) and polyvinylpyrrolidone-coated AgNPs (PVP-AgNPs). A good correspondence was obtained between predicted values and the total amount of AgNPs added with recovery values ranged within 80–160% for the individual mixtures, 68–108% for the binary mixtures and 60–64% for the ternary mixtures of AgNPs. Finally, transmission electron microscopy (TEM) measurements were performed for those cases where discrepancies between the expected and the obtained values were observed. TEM micrographs evidenced the presence of agglomerates or aggregates of AgNPs in some of the mixtures or water tested.Item In-vivo solid phase microextraction for quantitative analysis of volatile organoselenium compounds in plants(Analytica Chimica Acta, 2019) Moreno Martín, Gustavo; Sanz Landaluce, Jon; León González, María Eugenia De; Madrid Albarrán, María Yolanda; ElsevierA new calibration method based on the use of headspace solid-phase microextraction (HS-SPME) and in-fiber internal standardization, combined with gas chromatography coupled to mass spectrometry (GC/MS) was developed for quantifying Se volatile organic species released by plants exposed to chitosan-modified selenium nanoparticles (Cs-SeNPs). The effect of several parameters affecting extraction and separation of the selected organic species of selenium (dimethylselenium (DMSe), diethylselenium (DESe) and dimethyldiselenium (DMDSe)) and deuterated dimethyl sulphide (d6-DMS) employed as internal standard were studied and optimized using an experimental design. The developed methodology was applied for quantifying the volatile selenium compounds produced over time by the plant species Raphanus sativus and Brassica juncea grown in hydroponic solution containing 5 mg Se L−1 in the form Cs-SeNPs. The procedure employed consisted in two steps. Volatile selenium species released from the plants were first extracted in the SPME fiber located at the headspace of a box with a fixed volume. Subsequently, the internal standard placed in a vial subjected to the same conditions as plants was extracted on the same fiber than the one previously used for extracting selenium compounds. Finally the extracted compounds were separated and analyzed by GC/MS. Results evidenced Cs-SeNPs biotransformation into DMSe and DMDSe by both plants species during growing stage, in amounts of the order of ng. Additionally, the resulting data were submitted to multifactorial ANOVA to evaluate the influence of plant type and time of exposure to Cs-SeNPs on the production of volatile selenium compounds.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.