 This research paper investigated the extraction of caffeine and polyphenol from spent coffee grounds, SCGs. The authors optimized the extraction process using a response surface methodology, which resulted in a high yield of caffeine, 6.14 mg per g, and total polyphenol, 19.85 mg Gallic acid equivalents slash g. Additionally, the ferric-reducing antioxidant power and DPPH scavenging values were 136.69 mol ascorbic acid equivalents, slash g, and 230.41 mol DPPH, slash g, respectively. These results suggest that SCGs have great potential for use in the food industry due to their high levels of bioactive compounds. This article was authored by Theodoros Chatsomotakos, Vasilis Athanasaitis, Konstantina Katsu, and others.