Enhanced “Greener” and Sustainable Ultrasonic Extraction of Bioactive Components from Waste Wild Apple (Malus sylvestris (L.) Mill.) Fruit Dust: The Impact of Pretreatment with Natural Deep Eutectic Solvents

What if the dust from discarded wild apples could become a treasure trove of antioxidants? Scientists have found a green way to unlock its hidden value.

Industrialization has left us with dwindling resources and mounting pollution, but green chemistry is fighting back. In this study, researchers turned to an unlikely hero: waste wild apple dust, a by-product of the food industry. By combining ultrasonic extraction—a clean, efficient technology—with natural deep eutectic solvents (NADESs), they aimed to pull out bioactive compounds from this discarded material. The results were promising. Among various NADES pretreatments, aqueous propylene glycol paired with Reline NADES stood out, yielding the highest total phenolic content (TPC) and total flavonoid content (TFC), along with superior antioxidant activity. Chemical analysis via UHPLC-DAD-MS revealed a rich profile of natural organic acids, quercetin and kaempferol derivatives, tannins, and flavones. This approach not only valorizes agro-industrial waste but also offers extracts with potential uses in food and pharmaceuticals, contributing to cleaner production and a reduced environmental footprint. It's a win-win for industry and the planet.

Key Points

• Green combo: ultrasonic extraction + NADES solvents
• Aqueous propylene glycol with Reline NADES best
• Extracts rich in antioxidants, potential for food/pharma