Review on Extraction of Phenolic Compounds from Natural Sources Using Green Deep Eutectic Solvents

Can a jolt of electricity supercharge how we capture nature’s hidden health compounds? By combining pulsed electric fields with green solvents, scientists have unlocked a remarkably efficient way to harvest valuable molecules from sage leaves.

Researchers set out to explore how pulsed electric field (PEF) technology assists the extraction of phytochemicals from *Salvia officinalis* L., commonly known as sage. Testing pulse durations of 10 or 100 microseconds over 30 minutes, they evaluated eco-friendly solvents including pure ethanol, pure water, and various mixtures. These clever green extracts were then rigorously compared against traditional reference methods without PEF.

To measure success, the team looked closely at total polyphenols, individual polyphenols, volatile compounds, and the resulting resistance to oxidation. The sweet spot for maximum yield? A 25% aqueous ethanol solvent paired with a 100-microsecond pulse duration.

Under these optimal conditions, the results were striking. Total polyphenols and individual polyphenols—specifically rosmarinic acid—saw staggering extractability increases of up to 73.2% and 403.1%, respectively. Beyond just the polyphenols, this electric-assisted approach also measurably influenced the final concentration and composition of the extracts' volatile compounds.

Key Points

• Pulsed electric field-assisted extraction of sage leaves
• Tested 25% aqueous ethanol with 100 µs pulses
• Achieved up to 403.1% increase in specific polyphenols