IVAS 2022 banner
IVES 9 IVES Conference Series 9 IVAS 9 IVAS 2022 9 Peptides diversity and oxidative sensitivity: case of specific optimized inactivated yeasts

Peptides diversity and oxidative sensitivity: case of specific optimized inactivated yeasts

Abstract

Estimation of the resistance of a wine against oxidation is of great importance for the wine. To that purpose, most of the commonly used chemical assays that are dedicated to estimate the antioxidant (or antiradical) capacity of a wine consist in measuring the capacity of the wine to reduce an oxidative compound or a stable radical. In the must/wine matrix, polyphenols are major compounds likely to react with oxidant or radical, but such reaction generate quinones that then are involved in varietal aroma loss via nucleophilic addition reaction. It raises the paradox that a good antioxidant capacity does not imply a good protection of such sensitive compounds as aromatic compounds which are wine key quality markers.

The authors have developed a methodology focusing on the survival time of a sensitive compound to estimate the oxidative sensitivity of a solution. A labeled nucleophile is monitored by UHPLC-ESI-Q-ToF MS periodically for hours (from 0.5h to 72h) after a chemical initiation of oxidation in wine model solution containing 4-methylcatechol. 7 Cystein containing peptides (alone or in combination) are used to artificially increase the nucleophilic environment (and thus the competition for quinone nucleophilic addition) and estimate the half-life of the labeled nucleophile. In addition, soluble fraction released by different inactivated yeasts are also used as complex source of nucleophiles.

Half-life of the labeled compound is the final expression of several complex mechanisms such as nucleophilic competition, but also oxygen consumption, or catechol reduction.
Independently of the mechanisms, we can observe that increasing the nucleophilic environment improve the half life of the labeled nucleophile. It is notably visible for the specific optimized inactivated yeast which released many cysteine-containing peptides.
Finally, this method relies on the fate of one sensitive nucleophile to estimate the sensitiveness of the whole matrix to oxidation. It estimates the half-life of this compound which allows to compare oxidative sensitivity of different matrices under specific oxidation conditions.

DOI:

Publication date: June 23, 2022

Issue: IVAS 2022

Type: Article

Authors

Bahut Florian1, Sieczkowski Nathalie1, Nikolantonaki Maria1 and Gougeon Régis D.1

1Univ. Bourgogne Franche-Comté, AgroSup Dijon, PAM UMR A 02.102, Lallemand SAS, Institut Universitaire de la Vigne et du Vin – Jules Guyot, F-21000 Dijon, 19 rue des Briquetiers, BP 59, 31 702 Blagnac, France

Contact the author

Keywords

Nucleophile, oxidation, wine, peptide, diversity

Tags

IVAS 2022 | IVES Conference Series

Citation

Related articles…

Ecophysiological performance of Vitis rootstocks under water stress

The use of rootstocks tolerant to soil water deficit is an interesting strategy to cope with limited water availability. Currently, several nurseries are breeding new genotypes, but the physiological basis of its responses under water stress are largely unknown. To this end, an ecophysiological assessment of the conventional 110-Richter (110R) and SO4, and the new M1 and M4 rootstocks was carried out in potted ungrafted plants. During one season, these Vitis genotypes were grown under greenhouse conditions and subjected to two water regimes, well-watered and water deficit. Water potentials of plants under water deficit down to < -1.4 MPa, and net photosynthesis (AN) <5 μmol m-2 s-1 did not cause leaf oxidative stress damage compared to well-watered conditions in any of the genotypes. The antioxidant capacity was sufficient to neutralize the mild oxidative stress suffered. Under both treatments, gravimetric differences in daily water use were observed among genotypes, leading to differences in the biomass of root, shoot and leaf. Under well-watered conditions, SO4 and 110R were the most vigorous and M1 and M4 the least. However, under water stress, SO4 exhibited the greatest reduction in biomass while M4 showed the lowest. Remarkably, under these conditions, SO4 reached the least negative stem water potential (Ψstem), while M1 reduced stomatal conductance (gs) and AN the most. In addition, SO4 and M1 genotypes also showed the highest and lowest hydraulic conductance values, respectively. Our results suggest that there are differences in water use regulation among genotypes, not only attributed to differences in stomatal regulation or intrinsic water use efficiency at the leaf level. Therefore, because no differences in canopy-to-root ratio were achieved, it is hypothesized that xylem vessel anatomical differences may be driving the reported differences among rootstocks performance. Results demonstrate that each Vitis rootstock differs in its ecophysiological responses under water stress.

Modeling island and coastal vineyards potential in the context of climate change

Climate change impacts regional and local climates, which in turn affects the world’s wine regions. In the short term, these modifications rises issues about maintaining quality and style of wine, and in a longer term about the suitability of grape varieties and the sustainability of traditional wine regions. Thus, adaptation to climate change represents a major challenge for viticulture. In this context, island and coastal vineyards could become coveted areas due to their specific climatic conditions. In regions subject to warming, the proximity of the sea can moderate extremes temperatures, which could be an advantage for wine. However, coastal and island areas are particular prized spaces and subject to multiple pressures that make the establishment or extension of viticulture complex.
In this perspective, it seems relevant to assess the potentialities of coastal and island areas for viticulture. This contribution will present a spatial optimization model that tends to characterize most suitable agroclimatic patterns in historical or emerging vineyards according to different scenarios. Thanks to an in-depth bibliography a global inventory of coastal and insular vineyards on a worldwide scale has been realized. Relevant criteria have been identified to describe the specificities of these vineyards. They are used as input data in the optimization process, which will optimize some objectives and spatial aspects. According to a predefined scenario, the objectives are set in three main categories associated with climatic characteristics, vineyards characteristics and management strategies. At the end of this optimization process, a series of maps presents the different spatial configurations that maximize the scenario objectives.

Climate change projections to support the transition to climate-smart viticulture

The Earth’s system is undergoing major changes through a wide range of spatial and temporal scales as a response to growing anthropogenic radiative forcing, which is pushing the whole system far beyond its natural variability. Sources of greenhouse gases largely exceed their sinks, thus leading to a strengthened greenhouse effect. More energy is thereby being supplied to the system, with inevitable shifts in climatic patterns and weather regimes. Over the last decades, these modifications have been manifested in the full statistical distributions of the atmospheric variables, with dramatic changes in the frequency and intensity of extremes. Natural hazards, such as severe droughts, floods, forest fires, or heatwaves, are being triggered by extreme atmospheric events worldwide, thus threatening human activities. Viticultculture is not only exposed to changing climates but is also highly vulnerable, as grapevine phenology and physiological development are strongly controlled by atmospheric conditions. Therefore, the assessment of climate change projections for a given region is critical for climate change adaptation and risk reduction in viticulture. By adopting timely and suitable measures, the future sustainability and resiliency of the sector can be fostered. Climate-grapevine chain modelling is an essential tool for better planning and management. However, the accuracy of the resulting projections is limited by many uncertainties that must be duly taken into account when transferring knowledge to stakeholders and decision-makers. Climate-smart viticulture will comprise ensembles of locally tuned strategies, envisioning both adaptation and mitigation, assisted by emerging technologies and decision-support systems.

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…

Local adaptation tools to ensure the viticultural sustainability in a changing climate

[lwp_divi_breadcrumbs home_text="IVES" use_before_icon="on" before_icon="||divi||400" module_id="publication-ariane" _builder_version="4.19.4" _module_preset="default" module_text_align="center" module_font_size="16px" text_orientation="center"...