Fingerprinting as approach to unlock black box of taste

Grape canes are a non-recycled byproduct of wine industry (1-5 tons per hectare per year) containing valuable phytochemicals of medicine and agronomical interest. Resveratrol and wine polyphenols are known to exert a plethora of health-promoting effects including antioxidant capacity, cardioprotection, anticancer activity, anti-inflammatory effects, and estrogenic/antiestrogenic properties (Guerrero et al. 2009). Additionally, resveratrol is a major phytoalexin produced by plants in response to various stresses and promotes disease resistance (Chang et al. 2011). Our project aims to develop polyphenol-rich grape cane extracts to fight phytopathogenic or clinically relevant fungi. We initiate the project with the development of analytical methods to analyze resveratrol mono- and oligomers (dimers, trimers and tetramers) from grape canes and we evaluate their potential activity against clinically relevant opportunistic fungal pathogens (Houillé et al. 2014).

Context description and research question: an increasing number of farmers are considering the impact of conservation practices on soil health to guide sustainable management of vineyards. Understanding impacts of soil management on soil organic carbon (SOC) is one lever for adoption of agroecological practice with potential to help maintain or improve soil health while building SOC stocks to mitigate climate change (Amelung et al., 2020).

Esca complex is a disease affecting grapevine trunks, characterized by the colonization of the wood by xylem-residing fungi (Phaeomoniella chlamydospora, Phaeoacremonium minimum and Fomitiporia mediterranea), and posing significant risks to vineyard longevity since no efficient treatment is available. Despite its prevalence, the mechanisms beyond symptomatic manifestations like interveinal chlorosis and leaf necrosis remain unclear. Preliminary findings indicated a more pronounced metabolic reprogramming in fruits compared to vegetative organs and a putative impact on wine quality by using fruits from symptomatic grapevines.

Grape pomace (GP) is a winemaking by-product particularly rich in (poly)phenols and dietary fiber, which are the main active compounds responsible for its health-promoting effects. GP-derived products have been proposed to manage cardiovascular risk factors, including endothelial dysfunction, inflammation, hypertension, hyperglycemia, and obesity. Studies on the potential impact of GP on gut health are much more recent. However, it is suggested that, to some extent, this activity of GP as a cardiometabolic health-promoting ingredient would begin in the gastrointestinal tract as GP components (i.e., (poly)phenols and fiber) undergo extensive catabolism, mainly by the action of the intestinal microbiota, that gives rise to low-molecular-weight bioactive compounds that can be absorbed and utilized by the body.

ln 1997, twenty six cultivation sites of cv. Muscat of Alexandria different for pedological conditions, altitude and exposition were selected through ail Pantelleria isle. ln each site, described and classified according to USDA Soil Taxonony and FAO Soil Classification methods, grapes, collected at technological ripening, were microvinificated, following a standard procedure which allowed to obtain the naturally sweet wine DOC Moscato di Pantelleria. Wines, five months after vinification, were analysed by gaschromatography.