Green Extraction of Bioactives from Curcuma longa Using Natural Deep Eutectic Solvents: Unlocking Antioxidative, Antimicrobial, Antidiabetic, and Skin Depigmentation Potentials

Imagine a solvent so green it could make turmeric's golden treasures shine brighter than ever—without a drop of toxic chemistry. That's the promise of Natural Deep Eutectic Solvents, and they just outperformed plain water in unlocking turmeric's health secrets.

Turmeric has long been celebrated for its vibrant color and medicinal punch, but extracting its bioactive compounds has usually meant harsh solvents. Now, scientists tested 20 formulations of Natural Deep Eutectic Solvents (NADES)—blends of choline chloride with sugars, acids, glycerol, and more—to see if they could do better. The results are striking: two NADES mixes, one with choline chloride, 1,2-propanediol, and water (1:1:1) and another with glycerol, betaine, and water (1:1:3), pulled out 30.73 and 31.70 mg of curcumin per gram, respectively, beating water's 26.91 mg/g. But extraction was just the beginning. These green solvents didn't just collect turmeric's compounds; they supercharged them. The extracts showed boosted antioxidant power, strong antimicrobial effects, and impressive antidiabetic activity, with one NADES (ChCl/lactic acid/water 1:2:5) blocking 98.7% of tyrosinase—an enzyme behind skin pigmentation—and over 90% of α-amylase, a key target for diabetes management. This isn't just a lab curiosity; it's a step toward sustainable, eco-friendly extraction that could transform how we harness nature's pharmacy.

Key Points

• NADES outperform water in extracting curcumin from turmeric.
• Two NADES hit 30.73 and 31.70 mg/g curcumin yields.
• NADES 14 blocks 98.7% tyrosinase and >90% α-amylase.