Institut de Recerca en Nutrició i Seguretat Alimentària (INSA·UB)

Fingerprinting of quinoa grain protein extracts by liquid chromatography with spectrophotometric detection for chemometrics discrimination

2025-12-05T10:53:14Z

Fingerprinting of quinoa grain protein extracts by liquid chromatography with spectrophotometric detection for chemometrics discrimination Galindo Luján, Rocío del Pilar; Caballero-Alcázar, Nil; Pont Villanueva, Laura; Sanz Nebot, María Victoria; Benavente Moreno, Fernando J. (Julián) Quinoa (Chenopodium quinoa Willd.) grain is gaining great popularity worldwide because it is a rich source of nutrients, bioactive compounds, complete essential amino acids, and high-quality proteins. The demand for quinoa-based products is on the rise, which makes them prone to adulteration with less expensive cereals. In this study, we described a rapid and simple procedure for fingerprinting of quinoa grain protein extracts based on the combination of liquid chromatography with ultraviolet absorption diode array detection (LC-UV-DAD) and chemometrics. First, we developed a novel LC-UV-DAD method to obtain distinctive multiwavelength chromatographic profiles of protein extracts from various commercial quinoa grains, which encompass different quinoa varieties sold as black, red, white (from Peru), and royal (white from Bolivia). Then, the components of the LC-UV-DAD fingerprints were deconvoluted by multivariate curve resolution alternating least squares (MCRALS), and principal component analysis (PCA) followed by partial least squares discriminant analysis (PLS-DA) were applied to efficiently discriminate the commercial quinoa grains according to their differential composition. The chemometrics-assisted LC-UV-DAD fingerprinting methodology demonstrated its potential to rapidly and reliably discriminate quinoa grains according to the differential composition of their protein extracts and it may be applied in food quality and food fraud control.

Characterization of sparkling wine based on polyphenolic profiling by liquid chromatography coupled to mass spectrometry

2025-12-05T10:53:22Z

Characterization of sparkling wine based on polyphenolic profiling by liquid chromatography coupled to mass spectrometry Oliva, Eleonora; Mir-Cerdà, Aina; Sergi, Manuel; Sentellas, Sonia; Saurina, Javier Polyphenols are phytochemicals naturally present in wines that arouse much interest in the scientific community due to their healthy properties. In addition, their role as descriptors of various wine qualities, such as the geographical origin or the grape variety, cannot be underestimated. Here, Pinot Noir and Xarel·lo monovarietal samples belonging to the sparkling wine production process have been studied, corresponding to base wines from a first alcoholic fermentation (plus malolactic in some cases), base wines resulting from tartaric stabilization, and sparkling wines from a second alcoholic fermentation aged for 3 and 7 months. One of the objectives of this paper is to obtain valuable chemical and oenological information by processing a huge amount of data with suitable chemometric methods. High-performance liquid chromatography coupled with ultraviolet spectroscopy and tandem mass spectrometry (HPLC-UV-MS/MS) has been used for the determination of polyphenols in wines and related samples. The method relies on reversed-phase mode and further detection by multiple reaction monitoring. Concentrations of relevant phenolic compounds have been determined, and the resulting compositional data have been used for characterization purposes. Exploratory studies by principal component analysis have shown that samples can be discriminated according to varietal and quality issues. Further classification models have been established to assign unknown samples to their corresponding classes. For this purpose, a sequential classification tree has been designed involving both variety and quality classes, and an excellent classification rate has been achieved.

On-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry for the analysis of protein biomarkers in biological fluids and food: A tutorial

2026-04-08T13:34:04Z

On-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry for the analysis of protein biomarkers in biological fluids and food: A tutorial Vergara Barberan, Maria; Pont Villanueva, Laura; Salim, Hiba; Giménez López, Estela; Benavente Moreno, Fernando J. (Julián) The analysis by capillary electrophoresis (CE) of low abundant proteins in complex samples, such as biological fluids and food, is especially challenging, due to the poor concentration sensitivity of microscale separation tech- niques and the sample matrix complexity. In order to overcome these major drawbacks, microextraction sample preparation techniques based on on-line solid-phase extraction capillary electrophoresis (SPE-CE) are regarded as an excellent alternative for sample matrix clean-up and analyte preconcentration with minimum sample han- dling. In this study, we present, as a tutorial, a valve-free on-line aptamer affinity solid-phase extraction capillary electrophoresis-mass spectrometry (AA-SPE-CE-MS) method for purification, preconcentration, separation, de- tection, and characterization of intact protein biomarkers in biological fluids and food using as cases of study ‑synuclein ( ‑syn), concanavalin A (Con A), and -lactoglobulin ( -LG), which are related to Parkinson’s dis- ease and food allergy, respectively. This tutorial is not limited to the description of the analytical method, but it also provides ready-to-use preparation procedures for sorbent and microextraction devices, and introduces strategies to overcome undesired effects, allowing a straightforward implementation and optimum performance of AA-SPE-CE-MS, as a platform to develop further applications.

Prenatal exposure to persistent organic pollutants and sex-specific neonatal outcomes in the ENVIRONAGE birth cohort.

2026-04-08T13:33:53Z

Prenatal exposure to persistent organic pollutants and sex-specific neonatal outcomes in the ENVIRONAGE birth cohort. De Saeger, Sarah; Raes, Jeroen; Nawrot, Tim S.; Vanhaecke, Lynn; Covaci, Adrian; Cseresznye, Adam; Ouden, Fatima den; Engelen, Liesa; Maris, Elias; Ait Bamai, Yu; Paepe, Ellen De; Poma, Giulia; Derrien, Muriel; Vich Vila, Arnau; Hemeryck, Lieselot Y.; Peró Gascón, Roger Early-life exposure to environmental contaminants, such as endocrine disrupting persistent organic pollutants (POPs), including polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) and organochlorine pesticides (OCPs), is linked to adverse neonatal outcomes. However, the sex-specific effects of POP mixtures and the potential mediating roles of biological pathways, such as inflammation, remain insufficiently understood. This study aimed to investigate these aspects within the ENVIRONAGE birth cohort. The study population consisted of newborns (n = 402) from the ENVIRONAGE birth cohort, of which cord plasma levels of POPs were quantified using GC-ECNI/MS. Neonatal birth outcomes were derived from anthropometric measurements obtained at birth and via questionnaires completed postpartum. Among the 28 targeted POPs, nine were found in more than 50 % of the samples with CB 170, 180 and 153 detected in over 98 % of them. In single-pollutant models, several PCBs were inversely associated with ponderal index, while CB 118 was positively associated with head circumference in males (FDR-adjusted p < 0.05). Weighted Quantile Sum (WQS) regression revealed that in males, the POP mixture was inversely associated with birth weight (β = −141.21, p < 0.05) and ponderal index (β = −0.11, p < 0.01) and positively associated with head circumference (β = 0.53, p < 0.01) and the odds of preterm birth (OR = 2.91, p < 0.05). Conversely, among females, the POP mixture was associated with reduced odds of small-for-gestational-age (SGA) (OR = 0.21, p < 0.05) and below normal APGAR scores (OR = 0.39, p < 0.05). Mediation analysis indicated that the association between p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) and reduced birth weight/length was significantly mediated by eosinophil levels.