Ultrasound-Assisted Extraction of Phenolic Compounds from Celtuce (Lactuca sativa var. augustana) Leaves Using Natural Deep Eutectic Solvents (NADES): Process Optimization and Extraction Mechanism Research

Imagine turning lettuce leaves into a goldmine of antioxidants using a green, sugar-like solvent and sound waves. That's exactly what scientists just did—and they figured out how it works.

Natural deep eutectic solvents, or NADES, are the rising stars of green chemistry—non-toxic, biodegradable, and surprisingly effective at pulling valuable compounds out of plants. Yet until now, no one had tested them on celtuce leaves, a leafy vegetable often overlooked for its hidden phenolic treasures.

Researchers screened a specific NADES, L-proline-lactic acid (Pr-LA), and paired it with ultrasound-assisted extraction. The results were striking: Pr-LA outperformed traditional solvents, as confirmed by SEM and FT-IR, which showed the solvent shattered cell walls more effectively, releasing more phenolic compounds.

But the real magic lies in the mechanism. Molecular dynamics simulations revealed that Pr-LA forms stronger hydrogen bonds and van der Waals interactions with phenolics, boosting their solubility. The team then optimized the process using single-factor and Box–Behnken experiments, and a second-order kinetic model perfectly described the extraction under optimal conditions—offering a roadmap for industrial scale-up.

This isn't just a greener method; it's a deeper understanding of why it works. The study paves the way for NADES-based extraction to become mainstream, turning waste leaves into valuable sources of natural antioxidants.

Key Points

• Pr-LA NADES + ultrasound boosts phenolic extraction from celtuce leaves.
• SEM & FT-IR show enhanced cell wall disruption with Pr-LA.
• Kinetic model and simulations explain extraction mechanism for industry.