Sustainable valorization of functional phytochemicals from Polygonum multiflorum using natural deep eutectic solvents (NADES)

What if the secret to greener chemistry was hiding in a mix of apple acid and a common nutrient? Scientists just used it to unlock the power of a legendary medicinal plant.

Forget harsh solvents. Researchers turned to a natural deep eutectic solvent (NADES) made from malic acid and choline chloride to extract bioactive compounds from Reynoutria multiflora, also known as Polygonum multiflorum. By adding just 10% water, they created a 90% NADES system with improved viscosity and mass transfer, making the extraction process more efficient.

The optimized extract matched or even outperformed traditional solvents like hot water and 70% ethanol in yielding key compounds: THSG, emodin, and physcion. It also showed the highest enrichment of polymeric tannins and superior antioxidant activity across multiple tests. GC/MS profiling and PLS-DA revealed a distinct volatile spectrum, while the extract strongly inhibited lipid peroxidation and suppressed COX-2, pointing to anti-inflammatory potential.

Beyond the lab, this approach is built for industry. The NADES used is biodegradable, safe, and food-compatible, offering a viable alternative to conventional solvents. This method could turn P. multiflorum into a renewable crop for functional foods, nutraceuticals, and natural preservatives—and it might even extend to other underutilized crops, promoting a circular economy.

Key Points

• NADES (malic acid + choline chloride) with 10% water boosts extraction efficiency.
• Optimized extract yields THSG, emodin, physcion comparable to conventional solvents.
• Shows superior antioxidant, anti-inflammatory, and industrial viability.