Tentative identification of pyranoanthocyanins in Rioja aged red wines by high-performance liquid chromatography and tandem mass spectrometry

Abstract

Background and Aims:Pyranoanthocyanins are a type of derivative formed by the cycloaddition reaction of different compounds with anthocyanins during wine maturation and ageing, and show a characteristic pyranic ring. This ring provides a high stability to the pigment, and the ring does not fragment in mass spectrometric experiments. Thus, aglycone ions of these derivatives in tandem mass spectrometry show the same fragmentation pattern as that of the corresponding precursor anthocyanin. The aim of this work was the identification of pyranoanthocyanins present in Rioja aged wines using mass spectrometric features to differentiate among isomeric compounds. Methods and Results: The application to three Rioja aged red wines of a methodology that combines column chromatography, solid-phase extraction and high-performance liquid chromatography-diode array detectionelectrospray ionisation collision-induced dissociation-tandem mass spectrometry has allowed the identification of 72 pyranoanthocyanin derivatives. Conclusions: This paper provides an overview of pyranoanthocyanin derivatives present in aged red wines with the identification of 72 compounds, some of them derivatives that appear in low concentration, and it assesses the importance of mass spectrometric analysis in the differentiation among isomeric derivatives. Significance of the Study: The methodology described allows the identification of derivatives at low concentration and the establishment of characteristic fingerprints of native anthocyanins, which provide an effective tool for pyranoanthocyanin identification, allowing the differentiation among isomeric derivatives.

Structural identification and in vitro antioxidant activities of anthocyanins in black chokeberry (Aronia melanocarpa lliot)

“…There is no fluorescence under the ultraviolet lamp, indicating that there is no substituent at position 5 of the anthocyanin. After dropping aluminum chloride, the maximum absorption wavelength of the sample changed from 520 nm to 552 nm, showing obvious red shift, which indicates that in the structure of anthocyanins, ring B contains ortho‐phenolic hydroxyl [32], which is due to the decrease in the density of electrons on hydroxyl after adding aluminum chloride solution, resulting in the decrease of excitation energy and the shift of absorption peak to long wavelength, while anthocyanins without ortho‐phenolic hydroxyl will not show obvious red shift. After sodium methoxide was added, the absorption peak at 520 nm of the sample showed red shift, which indicated that the glycoside substituent in the anthocyanin structure of A. melanocarpa was at position 3 of the C ring [33].…”

Pre-drying and submerged cap winemaking: Effects on polyphenolic compounds and sensory descriptors. Part II: BRS Carmem and Bordô ( Vitis labrusca L.)

“…For peak assignation see Table 3. acetaldehyde, acetoacetic acid, hydroxycinnamic acids or vinylflavanols, giving rise to an orange hue for the red wines (Sánchez-Ilárduya et al, 2014). The second group was composed of some HCAD (coutaric and p-coumaroyl-glucose), the flavan-3-ol epicatechin gallate (ECG), the cis and trans resveratrol 3-glucosides (piceids), and two sensory descriptors, structure and color intensity.…”

Predicción del contenido de polifenoles totales de extractos de cacao, a partir del espacio de color CIElab

“…Los polifenoles de cacao están compuestos principalmente por flavanoles (catequinas, epicatequinas y procianidinas) y antocianinas (1). El grano de cacao sin fermentar tiene un color púrpura típico el cual puede darse por los compuestos derivados de las reacciones entre las antocianinas y flavanoles, las cuales pueden ocurrir directamente o por la presencia de acetaldehído en el grano de cacao el cual genera un puente etilo entre ambos compuestos (2). Cuando los flavanoles o las antocianinas sufren procesos oxidación por efecto de enzimas como la polifenol oxidasa y o por efecto de la temperatura estos colores pueden tornarse en un color amarronado (3).…”