In an era of escalating environmental challenges, converting organic residues into high-value bioactive compounds provides a sustainable way to reduce waste and enhance resource efficiency. This study explores the potential of the circular bioeconomy through the valorization of agricultural byproducts, with a focus on the antioxidant properties of specific chestnut burr cultivars. Currently, over one-third of food production is wasted, contributing to both humanitarian and environmental crises. Through circular bioeconomy, we can transform biological waste into valuable products for use in fields like food innovation and sustainability. The antioxidant effects of three chestnut cultivars, Bastarda Rossa, Cecio, and Marroni, were assessed through in vitro assays, highlighting their potential to combat oxidative stress—an important factor for health-related applications. The characterization of the three cultivars showed the major presence of ellagic acid and gallic acid in the extract, renowned for their antioxidant activity. In vitro assays evaluated the phenolic and flavonoid content, as well as the antioxidant activity of the three extracts, confirming the cultivar Cecio as the richest in these bioactive compounds and the most performative in antioxidant assays. In vitro antioxidant and oxidative stress recovery assays on SaOS-2, fibroblast, and chondrocyte cell lines displayed a strong antioxidant activity. Furthermore, the cytotoxicity assay demonstrated the safety of all three extracts in the tested human cell lines. In silico docking simulations further validated the biological relevance of these compounds by predicting strong hydrophobic and polar interactions with oxidative stress-related protein targets. Overall, this study demonstrates the antioxidant properties of chestnut byproducts. The findings contribute to the development of functional foods, nutraceuticals, and other applications, underscoring the role of chestnut cultivars in advancing circular bioeconomy practices.

Green chemistry principles are pivotal in driving sustainable and innovative solutions to global health challenges. This study explores a hydroalcoholic extract from Castanea sativa (chestnut) burrs, an underutilized natural resource, as a potent source of antimicrobial compounds against Helicobacter pylori (H. pylori). The extract demonstrated significant bactericidal activity, synergizing effectively with clarithromycin and showing additive effects with metronidazole. Remarkably, combining the extract with clarithromycin and sub-inhibitory concentrations of pantoprazole reduced clarithromycin’s Minimum Bactericidal Concentration (MBC) to just 1.56% of its original value. Mechanistic studies suggest that the extract’s polyphenolic compounds compromise bacterial membrane integrity, enhancing antibiotic uptake, while pantoprazole disrupts bacterial ATPase activity. This research highlights the critical role of natural product extraction within the framework of green chemistry, offering a sustainable and environmentally friendly alternative to synthetic antimicrobials. By harnessing bioactive compounds from plant sources, this approach addresses the pressing issue of antibiotic resistance while promoting the responsible use of natural resources. The findings underscore the transformative potential of green chemistry in developing effective, eco-conscious antimicrobial therapies that align with global sustainability goals.

The valorization of culinary by-products into functional bioactive resources represents a significant advancement in sustainable biotechnology. This study characterizes an extract derived from “battuto toscano” by-products, a traditional blend of garlic, onion, carrot, and celery trimmings, recovered through circular economy principles. Comprehensive antioxidant profiling was performed alongside biological evaluations on human cell lines and anti-glycation assays. Results from Folin–Ciocalteu, FRAP, and TEAC assays confirmed a high concentration of secondary metabolites with significant scavenging capacity. In vitro testing on primary human fibroblasts and HaCaT keratinocytes revealed a concentration- and time-dependent biological response, with lower concentrations showing better compatibility and transiently enhancing HaCaT metabolic activity. Furthermore, BTE reduced AGE-associated fluorescence in the BSA–glucose model, particularly at 5 mg/mL, supporting its potential anti-glycation activity. These findings establish “battuto toscano” by-products as a reservoir of sustainable biomolecules. This study offers a transformative resource for the pharma/nutraceutical sectors by bridging culinary tradition with biomedical innovation.