Optimization of Ultrasound-Assisted Extraction of Phenolic Compounds from Romanian Blackthorn (Prunus spinosa L.) Fruits

Hidden inside a wild, tart fruit from Romania's hedgerows lies a treasure chest of antioxidants—and scientists just found the perfect key to unlock it.

Blackthorn fruits, small and unassuming, are packed with phenolic compounds—natural antioxidants that could benefit health. But getting them out efficiently is a puzzle. Researchers turned to ultrasound-assisted extraction (UAE), a green technique using sound waves and ethanol-water mixtures, to crack this puzzle without harsh chemicals.

They screened six factors—solvent-to-plant ratio, ethanol concentration, temperature, pH, ultrasonic amplitude, and time—using a Plackett-Burman design to spot the big players. Then, a central composite design fine-tuned the process. The results were clear: solvent ratio, ethanol concentration, and temperature mattered most.

Under optimal conditions—15.1 cm³/g solvent, 33.2% ethanol, 66.8°C, pH 7, 50% amplitude, and 10 minutes—they achieved a total phenolic content of 14.45 mg GAE/g dry matter, with notable antioxidant capacity. The extract also revealed six specific phenolic compounds, including rutin and chlorogenic acid, each quantified precisely.

This isn't just lab trivia. It's a roadmap for turning a humble wild fruit into a valuable source of bioactive compounds, sustainably and efficiently.

Key Points

• Ultrasound-assisted extraction optimizes polyphenol yield from blackthorn fruits.
• Key factors: solvent ratio, ethanol concentration, and temperature.
• Optimal conditions yield 14.45 mg GAE/g TPC and six identified phenolics.