Ensuring healthy lives and well-being constitutes one of the Sustainable Development Goals of the UN 2030 agenda. Consequently, research into how natural products may promote health is essential for the new generation of nutraceuticals and functional foods that are in high demand today. Grape juice is a natural foodstuff composed of water, sugars, minerals, vitamins and a wide array of polyphenols. Polyphenols are bioactive compounds of great interest due to their antioxidant properties and benefits to health, supporting antimicrobial, anti-aging, and anticarcinogenic activity. The majority of grape juice produced in the world is used for the production of wine, although a small part is used in the food industry, mainly in baby food and sports drinks. The aim of this work is to determine the polyphenol content in the natural and concentrated juice of Airen grapes, the main white grape variety produced in Spain. For this, fresh juices from five grape varietals (Airen, Sauvignon Blanc, Gewürztraminer, Verdejo and Tempranillo) and concentrated Airen juice were analyzed and compared. Results showed similar contents of phenolic acids and stilbenes in all grape varietals studied, although the Airen variety demonstrated a higher concentration of two flavonoids: quercetin and catechin. It can be concluded that the grape juice concentration process negatively affects the stability of these compounds, causing a reduction in the polyphenol content that ranges between 54–71%, with the exception of quercetin and catechin.

Leukemia is a heterogeneous group of hemopoietic cancers, which accounts for 2.6% of new cases per year of total cancer incidence worldwide. Grapes and grapederived products, such as grape juice, are naturally rich in polyphenols, bioactive compounds with antioxidant properties. Certain polyphenols have been proved to alter oxidative balance, both in inducing apoptosis in cancer cells and in preventing cancer development via controlling oxidative stress. To assess the therapeutic potential of grape polyphenols in the treatment of leukemia, a systematic review and meta-analysis of the reported data on leukemia was carried out. Following the PRISMA guide, a literature review of published papers on leukemia and polyphenols from the last 50 years was conducted, and 17 scientific articles published from 2002-2017 were included in the study. Resveratrol 50 m had the highest growth inhibition effect (67%) followed by quercetin (30%). The results also point to a differential effect of polyphenols based on cell lineage; monocytes-and myelocytic-derived cell lines are the most susceptible, with a mean of 85% and 64% proliferation inhibition, respectively. Moreover, results show that growth inhibition cannot be associated with a molecular effect of polyphenols on the cell cycle arrest.