Green Extraction of Bioactive Phenolics From Withania somnifera Using Deep Eutectic Solvents: Efficiency, Antioxidant Potential, and Antibacterial Activity

What if the secret to unlocking nature's powerful antioxidants lies in a solvent that's both green and recyclable? A new study reveals how deep eutectic solvents can extract flavonoids from Fagonia cretica with remarkable efficiency and sustainability.

Imagine a solvent that's not only effective but also kind to the planet. Researchers have been exploring deep eutectic solvents (DESs) as a greener alternative to traditional extraction methods. In a recent study, they optimized the extraction of flavonoids from Fagonia cretica, a plant known for its medicinal properties, using six different DESs. The standout performer was a betaine–acetic acid combination, thanks to its low viscosity of just 4.98 mPa·s, which allowed for better penetration and extraction efficiency.

The team pinpointed the perfect conditions: a 1:4 molar ratio of betaine to acetic acid, 25% water content, a solid/liquid ratio of 1:60 g/mL, and a temperature of 50°C for 30 minutes. Under these optimal settings, flavonoid yield was maximized while preserving bioactivity. But the benefits didn't stop there. The extracted flavonoids showed superior scavenging activity against DPPH and hydroxyl radicals compared to those obtained with ethanol, highlighting DESs' potential to boost antioxidant properties.

Sustainability was a key focus. The DESs were recycled using ultracapacitor porous activated carbon, achieving an impressive 89.78% recovery efficiency. Even after six cycles, the reused DES maintained a high extraction yield, retaining 92% efficiency. This demonstrates that DES-based extraction is not only efficient but also cost-effective and environmentally friendly, offering a promising path for green chemistry and bioactive compound recovery.

Key Points

• Betaine–acetic acid DES showed highest extraction efficiency due to low viscosity.
• Optimal conditions: 1:4 molar ratio, 25% water, 1:60 g/mL, 50°C, 30 min.
• DESs recyclable: 89.78% recovery, 92% yield after six cycles.