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.

Sustainable fertilisation of the vineyard in Galicia (Spain)

Excessive fertilization of the vineyard leads to low quality grapes, increased costs and a negative impact on the environment. In order to establish an integrated management system aimed at a sustainable fertilization of the vineyards, nutritional reference levels were established. For this purpose, 30 representative vineyards of the Albariño variety were studied, in which soil and petiole analyses were carried out for two years and grape yield and quality at harvest were measured. In both years of study, soil pH, calcium, sodium and cation exchange capacity were positively correlated with calcium content and negatively correlated with manganese in grapes. Irrigated vineyards had higher levels of aluminium in soil and lower levels of calcium in petiole. Climatic conditions were very different in the years of the study. The year 2019 was colder than usual, in 2020 there was a marked water stress with high summer temperatures. This resulted in medium-high acidity in grapes in 2019 and low acidity in 2020, with sugar levels being similar both years. A very marked decrease in must amino nitrogen was observed in 2020, with ammonia nitrogen remaining stable. The correlation of acidity and sugar values in grapes with soil and petiole analysis data made it possible to establish reference levels for the nutritional diagnosis of the Albariño variety in this region. Based on these results, an easy-to-use TIC application is currently being created for grapegrowers, aimed at improving the sustainability of the vineyard through reasoned fertilization. This study has now been extended to other Galician vine varieties.

Climate, Viticulture, and Wine … my how things have changed!

The planet is warmer than at any time in our recorded past and increasing greenhouse emissions and persistence in the climate system means that continued warming is highly likely. Climate change has already altered the basic framework of growing grapes for wine production worldwide and will likely continue to do so for years to come. The wine sector can continue to play an important role in leading the agricultural sector in addressing climate change. From developing on…

Assessing the relationship between cordon strangulation, dieback, and fungal trunk disease symptom expression

Grapevine trunk diseases including Eutypa dieback are a major factor in the decline of vineyards and may lead to loss of productivity, reduced income, and premature reworking or replanting. Several studies have yielded results indicating that vines may be more likely to express symptoms of vascular disease if their health is already compromised by stress. In Australia and many other wine-growing regions it is a common practice for canes to be wrapped tightly around the cordon wire during the establishment of permanent cordon arms. It is likely that this practice may have a negative effect on health and longevity, as older cordons that have been trained in this manner often display signs of decay and dieback, with the wire often visibly embedded within the wood of the cordon. It is possible that adopting a training method which avoids constriction of the vasculature of the cordon may help to limit the onset of vascular disease symptom expression. A survey was conducted during the spring of two consecutive growing seasons on vineyards in South Australia displaying symptoms of Eutypa lata infection when symptomless shoots were 50–100 cm long. Vines were assessed as follows: (i) the proportion of cordon exhibiting dieback was rated using a 0–100% scale; (ii) the proportion of canopy exhibiting foliar symptoms of Eutypa dieback was rated using a 0–100% scale; (iii) the severity of strangulation was rated using a 0–4 point scale. Images were also taken of each vine for the purpose of measuring plant area index (PAI) using the VitiCanopy App. The goal of the survey was to determine if and to what extent any correlation exists between severity of strangulation and cordon dieback, in addition to Eutypa dieback foliar symptom expression.

Vineyards and clay minerals: multi-technique analytical approach and correlations with soil properties

Purpose of this research is to quantitatively assess the mineral component of vineyard soils, with particular attention to the mineralogical analysis of clays, which represent an element of high importance in the vineyard culture as well as in general agriculture. An X-ray diffraction (XRD) / thermogravimetric (TG) multi-technique analytical approach was developed, tested on soil samples taken from vineyards around the world. This codified analytical procedure was necessary to obtain precise qualitative and quantitative mineralogical data, globally comparable to distinguish the geopedological identity of the vineyards. Soil samples from vineyards of various locations were analysed, in very different geological conditions. The bulk-rock quantitative phase analysis (QPA) was obtained by the Rietveld method while the detailed composition of the clay-sized fraction was determined by modelling of the oriented X-ray diffraction patterns. The research provided a precise classification of the mineral component of soils, distinguishing the mineral phases of the clays and the so-called mixed-layer clay minerals. We found that the content in mixed layers can be directly correlated with the water retention and the cation exchange capacity ​​of the soil, while the presence of other clayey minerals and phyllosilicates in this research did not affect this CEC parameter, which codes the fertility level of the soils. The study demonstrates that terroir, in particular soils formed in complex or very different geological conditions, can only be effectively interpreted by properly analysing its mineral phases, in particular the mixed-layer clay component. These are characteristic abiotic ecological indicators, which may have specific eco-physiological influences on the plant.