Combining natural deep eutectic solvent and microwave irradiation towards the eco-friendly and optimized extraction of bioactive phenolics from Eugenia uniflora L.

What if the secret to greener pharmaceuticals was hidden in the leaves of a Brazilian plant—and a simple kitchen microwave could unlock it?

In the quest for sustainable chemistry, researchers are turning to nature's own solvents. A new study combines natural deep eutectic solvents (NADES) with microwave irradiation to extract bioactive phenolics from Eugenia uniflora L., a plant used in folk medicine and listed by Brazil's health system as a potential source for phytomedicines. The goal: make extraction greener without sacrificing efficiency.

The team screened five food-compatible NADES and found that choline chloride:lactic acid (1:3 mol/mol) with 20% water worked best. Using a statistical design, they optimized conditions like plant-to-solvent ratio, irradiation time, and temperature. The result was a polyphenolic extract ready for use without extra purification steps—something previous methods using volatile organic solvents couldn't achieve.

Environmental impact was measured with three complementary metrics (HPLC-EAT, Analytical Eco-Scale, and GAPI), confirming the approach is more sustainable. This integrated method—NADES, microwaves, and design of experiments—offers a rational, eco-friendly blueprint for extracting phenolics from plants, potentially extending to other species.

Key Points

• NADES with microwave boosts phenolic extraction from Eugenia uniflora.
• Choline chloride:lactic acid (1:3) + 20% water is optimal.
• Eco-friendly method beats volatile organic solvents, no purification needed.