Potential health benefits of phenolic compounds in grape processing by-products

Abstract

Prevention emerges as a powerful approach in minimizing the risk of deleterious lifestyle diseases because therapies do not necessarily guarantee a permanent cure. Accordingly, consumers' growing preference for natural and health-promoting dietary options that are rich in antioxidants has become widespread. Grape (Vitis vinifera) is an antioxidant-rich fruit extensively grown for fresh or processed consumption. The long-term consumption of its polyphenolic antioxidants may promote multiple health benefits. However, grape pomace (GP), consisting of peel, seed, stem, and pulp, is discarded during grape processing, including juice extraction and winemaking, despite its substantial antioxidant content. Polyphenolic extraction techniques have been widely explored to date, but the consolidation of reported physiological impacts of GP-derived polyphenolic constituents is limited. Thus, this review highlights current studies of the potential applications of GP extract in disease prevention and treatment, emphasizing the major influence of polyphenolic compositions and origins of different grape varieties.

Nutrigenomic Effects of Long-Term Grape Pomace Supplementation in Dairy Cows

“…Grape pomace accounts for ~25%-35% of the total weight of processed grapes; it contains significant amounts of dietary fiber, for which it may partially replace the forage portion in ruminants' diet [22,37]. Far more interesting, GP is enriched with potent bioactive compounds, especially polyphenols (~2%-6.5%).…”

“…The objective of this study was to examine the transcriptomic signature of a long-term dietary GP supplementation in dairy cows and to evaluate whether this signature reflects known GP-associated potential health benefits [37]. The main finding was that a 60-day dietary GP supplementation can modulate the expression of a considerable, albeit less than expected, number of genes in dairy cows and induce a noticeable transcriptomic signature that mainly reflects a GP-induced immunomodulatory effect.…”

“…Far more interesting, GP is enriched with potent bioactive compounds, especially polyphenols (~2%-6.5%). Grape polyphenolics, possessing different chemical structures and activities, are essentially categorized into two major classes of compounds: flavonoids (the most abundant polyphenols) and non-flavonoids [37,39,41]. Even though the biological activity of GP extracts mostly relate to their antioxidant properties, the dietary intake of these bioactive compounds results in pleiotropic health-promoting responses, e.g., cardio-and neuroprotective, anti-diabetic, anti-cancer, anti-aging, anti-adipogenetic as well as prebiotic and anti-microbial beneficial effects [39,[41][42][43].…”

Grape Pomace Valorization: A Systematic Review and Meta-Analysis

“…The main representatives of polyphenolic compounds in this byproduct are anthocyanins (only in red grape pomaces), catechins, flavonol glycosides, phenolic acids, and alcohols [31]. Together with dietary fibers, phenolic compounds are the most valuable compounds of grape pomace with health beneficial properties, such as the maintenance of intestinal health and the prevention of chronic diseases and cancer [9,32]. Many studies showed the great antioxidant potential of polyphenols and their use in food preservation due to the inhibition of lipid oxidation and antibacterial effect [33].…”

Grape Stem Extracts with Potential Anticancer and Antioxidant Properties

“…According to current research results, grape stem extracts possess important biological activities with multiple benefits for human health due to antioxidant and anti-inflammatory properties [ 5 , 7 , 8 , 9 , 10 , 11 ]. Veskoukis et al [ 10 ] found that this by-product is particularly rich in flavonoids and stilbenes, such as trans -resveratrol and viniferin, which are found in considerably high concentrations.…”