Green recovery of phenolics from bitter orange flowers: Natural deep eutectic solvent-ultrasound synergistic extraction, adsorptive purification, and UPLC/Q-TOF-MS/MS analysis

Bitter orange flowers hide a treasure of health-boosting phenolics—but old extraction methods waste them. Now, a green, ultrasound-powered recipe unlocks them more efficiently than ever before.

Bitter orange flowers aren't just a pretty bloom—they're a medicinal and edible powerhouse packed with phenolic compounds. Yet, pulling these bioactive molecules out efficiently has long been a challenge. Researchers have now crafted a green solution: a natural deep eutectic solvent paired with ultrasound, a combination that gently but powerfully extracts phenolics from the flowers.

After screening 12 solvents, choline chloride-ethylene glycol emerged as the winner. Fine-tuned with a statistical design, the method achieved a remarkable yield of 104.58 mg per gram of flower—1.3 to 2.16 times higher than conventional solvents. The process is fast, uses mild heat, and leaves no toxic residue.

Next, the team purified the extract using AB-8 resin, which adsorbed the phenolics in a predictable, spontaneous, and exothermic manner. This step boosted purity to over 75%, setting the stage for precise analysis. With UPLC-Q/TOF-MS/MS, they identified and measured seven bioactive compounds, creating a reliable quality-control blueprint.

This integrated approach isn't just a lab trick—it's a sustainable template for recovering valuable plant compounds, proving that going green can also be going smart.

Key Points

• NADES-ultrasound yields 104.58 mg/g phenolics, 1.3-2.16x higher than conventional.
• AB-8 resin purifies extract to 75.62% purity via spontaneous physisorption.
• UPLC-Q/TOF-MS/MS identifies 7 bioactive compounds for quality control.