IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Screening of hydroxytyrosol and tyrosine related metabolites in commercial wines by an UHPLC/MS validated method.

Screening of hydroxytyrosol and tyrosine related metabolites in commercial wines by an UHPLC/MS validated method.

Abstract

Hydroxytyrosol (HT) is a bioactive phenolic compound with antioxidant activity. Yeast synthetise tyrosol from tyrosine by the Ehrlich pathway which is subsequently hydroxylated to HT. The aim of the present work is to develop and validate an UHPLC–HRMS method to assess the metabolites involved in this pathway as well as to screen Spanish commercial wines for HT bioactive compound.

A total of 100 samples of commercial wines were analysed including 57 red wines and 43 white. The analysis was carried out in a Waters Acquity UHPLC (Milford, Massachusetts, USA) coupled to a Waters Xevo TQ (Milford, Massachusetts, USA) triple quadrupole mass spectrometer. The MassLynx MS software was used. The column used was an Acquity UPLC BEH C18. The chromatographic conditions consisted of two mobile phases, water with 0.2% acetic acid (A) and acetonitrile (B), with a gradient elution programmed.

This analytical method was validated following AOAC instructions (AOAC 2012). Linearity, LOD, LOQ, intermediate accuracy, repeatability and matrix effects were the parameters assessed.  Calibration standards were prepared for each analytical batch and three replicates were determined at different concentrations for each compound with 7 degrees of linearity.

Linearity values were calculated through the correlation coefficient (R2) of the curves obtained for each compound. The detection limits were calculated based on the standard deviation of the response and the slope (Ich, 2005).

The intermediate precision was calculated measuring standard deviation (RSD) in a set of three concentrations (LOQ, 10x LOQ and 100x LOQ ng mL−1) for 5 days with 6 replicates per concentration. Repeatability was assessed in a single day-long work session, with six replicates of each concentration.

The matrix effect was tested in a wine synthetic matrix by spiking with the same standard
solution as described above. The slopes resulting from the spiked matrix and calibration solutions (acetonitrile 10% v/v) in the linear range were used to evaluate the matrix effect.

In order to elucidate the effect that filtration caused on the compounds, most usual filters such as nylon (NY), polytetrafluoroethylene (PTFE) and cellulose acetate (CA) were tested. In the case of hydroxytyrosol the LOD was 0.052 ng mL−1 and LOQ 0.157 ng mL-1. For tyrosol, LOD 13,020 and LOQ 39,455 ng mL -1. Tyrosine, LOD 1,567 and LOQ 4,748 ng mL−1 and hydroxyphenylpyruvic acid, LOD 6,795 and LOQ 20,591 ng mL-1. All the values had an R2 between 0.9991 and 0.9999, showing quite good linearity. As we know, this is the first study available in which all the compound of the formation route for hydroxytyrosol has been identified and quantified. This could be accomplished thanks to a validated HRM method developed specifically to diminish LOD and LOQ. Furthermore, we ascertained the differences in the content of hydroxytyrosol in a great range of Spanish wines.

References

AOAC (2012) Appendix F: guidelines for Standard Method Performance
Requirements (SMPR). AOAC Official methods of analysis.
Ich (2005). ICH Topic Q2 (R1) Validation of analytical procedures: Text and methodology. International Conference on Harmonization, 1994 (November 1996), 17.

DOI:

Publication date: June 24, 2022

Issue: IVAS 2022

Type: Poster

Authors

González-Ramírez Marina1, Valero Eva2, Cerezo Ana B.1, Troncoso Ana M.1 and Garcia-Parrilla M. Carmen1

1Departamento de Nutrición y Bromatología, Toxicología y Medicina Legal, Facultad de Farmacia, Universidad de Sevilla
2Departamento de Biología Molecular e Ingeniería Bioquímica, Universidad Pablo de Olavide, Sevilla, Spain

Contact the author

Keywords

hydroxytyrosol, wine, UHPLC, mass spectrometry, tyrosine.

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Biodiversity in the vineyard agroecosystem: exploring systemic approaches

Biodiversity conservation and restoration are essential for guarantee the provision of ecosystem services associated to vineyard agroecosystem such as climate regulation trough carbon sequestration and control of pests and diseases. Most of published research dealing with the complexity of the vineyard agroecosystems emphasizes the necessity of innovative approaches, including the integration of information at different temporal and spatial scales and development of systemic analysis based on modelling. A biodiversity survey was conducted in the Franciacorta wine-growing area (Lombardy, Italy), one of the most important Italian wine-growing regions for sparkling wine production, considering a portion of the territory of 112 ha. The area was divided into several Environmental Units (EUs), defined as a whole vineyard or portion of vineyard homogenous in terms of four agronomic characteristics: planting year, planting density, cultivar, and training system. In each EU a set of compartments was identified and characterised by specific variables. The compartments are meteorology, morphology (altitude, slope, aspect, row orientation, and solar irradiance), ecological infrastructures and management. The landscape surrounding EU was also characterised in terms of land-use in a buffer zone of 500 m. For each component a specific methodology was identified and applied. Different statistical approaches were used to evaluate the method to integrate the information related to different compartments within the EU and related to the buffer zone. These approaches were also preliminarily evaluated for their ability to describe the contribution of biodiversity and landscape components to ecosystem services. This methodological exploration provides useful indication for the development of a fully systemic approach to structural and functional biodiversity in vineyard agroecosystems, contributing to promote a multifunctional perspective for the all wine-growing sector.

Influence of climatic conditions on grape composition of Tempranillo in La Mancha DO (Spain)

The aim of this work was to analyze the variability in grape composition of the Tempranillo cultivar related to climatic conditions, in La Mancha Designation of Origin. Grape composition (sugar content, total acidity, pH, malic acid, and total and extractable anthocyanins) recorded during ripening, were analysed for the period 2000-2019. The weather conditions at daily time scale, recorded during the same period, were also evaluated. The relationships between grape parameters with climatic variables related to temperature and to water deficits, referring different periods between phenological events along the growing cycle, were evaluated using regression analysis. High variability in grape composition was observed in the period analysed. Total acidity varied between 3.7 and 7.3 gL-1 while malic acid varied between 1.2 and 4 gL-1. The extractable anthocyanins ranged between 526 and 972 mgL-1, and total anthocyanins ranged between 922 and 1388 mgL-1, being the lowest values recorded in the hottest year (2017). Total acidity decreased 0.77 gL-1 for an increase of 100 GDD, while malic acid decrease in 0.42 gL-1 for the same GDD increase, being the period between veraison and harvest the one that seemed to have higher influence on acidity. In addition, it was confirmed that increasing water deficits decreased acidity. Total and extractable anthocyanins increased in about 210 and 105 mgL-1, respectively, with an increase of 100 GDD from veraison to harvest, and the increase in water deficits favour the increase of anthocyanins, both total and extractable anthocyanins. Total and extractable anthocyanins concentration increased in 35 and 22 mgL-1 per an increase of 10 mm in the water deficit. These results can be of interest to understand the potential changes that grapes composition may suffer under future warmer climates.

Diagnosis of soil quality and evaluation of the impact of viticultural practices on soil biodiversity in a vineyard in southwestern France

Viticulture is facing two major changes – climate change and agroecological transition. In both cases, soil quality is seen as a lever to move towards a more sustainable viticulture. However, soil biological quality is little considered in the implementation of viticultural practices. Gascogn’Innov (2017-2022) is an Operational Group funded by the European Innovation Partnership for Agriculture. As such, it brings together winegrowers from the south-west of France, scientists, advisors and technicians, around a project focused on viticultural soil biological functioning and the design of technical routes more respectful toward soil heritage. To achieve this, the project aims to acquire references on the impact of viticultural practices on soil biology from a dynamic way, and to test a methodology to integrate information provided by the soil bioindicators to manage farming systems. A set of indicators of soil biological quality are evaluated in the project: microorganisms (bacteria and fungi abundance and diversity), fauna (abundance and diversity of nematodes and earthworms), physico-chemical characteristics, soil structure assessment and degradation rate of organic matter. Based on a network of 13 plots that have been subject to an initial diagnosis in 2017, several agronomical practices to restore soil fertility are experimented to redesign the cropping system (for instance plant cover, organic matter inputs, reduction of herbicides, mineral fertilizers). System redesign was made in collaboration by winegrowers and an interdisciplinary group of experts (agronomists, biologists). Several indicators are measured on vine and soil at each vintage to assess vine health and productivity. At the end of the project (2021), a final diagnosis was carried out. Gascogn’Innov allowed to create a regional database on the quality of wine-growing soils, which permitted to evaluate the effect of practices according to soil types. Especially, decreasing the intensity of tillage and increasing the duration and diversity of grass coverage tends to increase the abundance of all the organisms studied. This project confirmed the value of soil biological quality indicators to drive the sustainability of practices, but also highlighted the key-role of expertise, in both agronomy and soil biology, to help winegrowers understand and appropriate their soil quality diagnoses.

Sustaining wine identity through intra-varietal diversification

With contemporary climate change, cultivated Vitis vinifera L. is at risk as climate is a critical component in defining ecologically fitted plant materiel. While winegrowers can draw on the rich diversity among grapevine varieties to limit expected impacts (Morales-Castilla et al., 2020), replacing a signature variety that has created a sense of local distinctiveness may lead to several challenges. In order to sustain wine identity in uncertain climate outcomes, the study of intra-varietal diversity is important to reflect the adaptive and evolutionary potential of current cultivated varieties. The aim of this ongoing study is to understand to what extent can intra-varietal diversity be a climate change adaptation solution. With a focus on early (Sauvignon blanc, Riesling, Grolleau, Pinot noir) to moderate late (Chenin, Petit Verdot, Cabernet franc) ripening varieties, data was collected for flowering and veraison for the various studied accessions (from conservatory plots) and clones. For these phenological growing stages, heat requirements were established using nearby weather stations (adapted from the GFV model, Parker et al., 2013) and model performances were verified. Climate change projections were then integrated to predict the future behaviour of the intra-varietal diversity. Study findings highlight the strong phenotypic diversity of studied varieties and the importance of diversification to enhance climate change resilience. While model performances may require improvements, this study is the first step towards quantifying heat requirements of different clones and how they can provide adaptation solutions for winegrowers to sustain local wine identity in a global changing climate. As genetic diversity is an ongoing process through point mutations and epigenetic adaptations, perspective work is to explore clonal data from a wide variety of geographic locations.

Influence of a spontaneous cover crop on the vineyard and soil erosion under Mediterranean climate

Sixty five % of the agricultural area of the Basque Country located in the DO Ca Rioja corresponds to vineyards. More than 40% of it has an average slope greater than 10%, which makes it sensitive to erosive processes. Furthermore, it is foreseeable that extreme weather events (storms, hail, extreme heat and cold, etc.) will be favored due to climate change. Cover cropping can mitigate this risk, and therefore the objective of this work is to evaluate the impact that a vegetable cover has on the agronomic behavior of the vineyard, the quality of the grape and soil erosion. For this, a trial has been carried out with a Graciano variety vineyard with a slope between 10% -20% during the years 2020 and 2021. Conventional tillage management in the area has been compared (4-6 passes per year of tillage machinery) versus spontaneous vegetation cover management in the vineyard. This implies not tilling and allowing the grass of the land to colonize the range between the lines of vines, controlling their height through 1-3 mowing passes per year, always trying to affect the surface of the land as little as possible. The vegetative growth, yield and quality of the grape and wine was measured. Furthermore, erosion has been measured using Gerlasch boxes. The yield was lower in the second year of the trial in the cover crop treatment, but erosion was significantly reduced.