The effect of hydrogen bonding strength in natural deep eutectic solvents on the extraction efficiency of polyphenols

This study explored the extraction of polyphenols from Juniperus chinensis Roxb. using natural deep eutectic solvents (NADES), emphasizing the role of hydrogen bonding strength in enhancing extraction efficiency. Choline chloride-fructose emerged as the most effective NADES after evaluating the correlation between hydroxyl stretching vibrations and polyphenol yield. Using the response surface methodology, the optimal extraction process (liquid to solid ratio 50.6 mL/g, extraction temperature 41.1 degrees C, extraction time 29.8 min, ultrasonic time 14.9 min) was determined to have a yield of 27.90 +/- 0.14 mg/g, more than double that of water extraction. Choline chloride-fructose showed a more pronounced disruptive effect on plant powders. Additionally, compared to water extracts, the extracts using choline chloride-fructose exhibited higher antioxidant potential and quercitrin content. Overall, this study explores the correlation between hydrogen bond strength and extraction yield, while optimizing a green and efficient alternative process for polyphenol extraction from plants. These findings align with green chemistry principles, contributing to the development of sustainable and environmentally friendly extraction methods.