Ultrasound-assisted extraction, optimization, and purification of total flavonoids from <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si10.svg"><mml:mrow><mml:mi mathvariant="italic">Daphne</mml:mi><mml:mspace width="0.35em"/><mml:mi mathvariant="italic">genkwa</mml:mi></mml:mrow></mml:math> and analysis of their antioxidant, anti-inflammatory, and analgesic activities
Yi Xiang, Zheng Liu, Yanzhi Liu, Bin Dong, Chang-qing Yang, Hanhan Li
Abstract
• Optimize the ultrasonic-assisted extraction conditions of Daphne genkwa and determine five optimal extraction parameters. • Identify and quantify four representative and biologically active flavonoid components in Daphne genkwa. • The ultrasound extracted total flavonoids from Daphne genkwa have antioxidant activity and anti-inflammatory and analgesic properties. • Provide a theoretical basis and experimental support for further developing the industrial application and medicinal value of Daphne genkwa. Daphne genkwa (D. genkwa) is the dried flower buds of a Chinese medicinal plant with multiple biological activities. Response surface methodology (RSM) combined with artificial neural network (ANN) techniques were utilized to optimize ultrasound-assisted extraction conditions for D. genkwa . Antioxidant activity and anti-inflammatory and analgesic properties of total flavonoids from D. genkwa (TFDG) were assessed. Optimal conditions involving ultrasonic power of 225 W, 30 min extraction time, 30 mL/g liquid–solid ratio, 60 °C extraction temperature, and 70% ethanol concentration yielded a maximum total flavonoids content (TFC) of 5.41 mg/g. After microporous resin purification, four specific flavonoids in D. genkwa were identified and quantified using high-performance liquid chromatography (HPLC). The TFDG demonstrated potent antioxidant activity, with a 94% rate of scavenging the 2, 2-diphenyl-1-picrylhydrazyl (DPPH). Furthermore, TFDG exhibited pain-alleviating properties in hot plate and acetic acid-induced writhing tests and noteworthy inhibitory effects on xylene-induced ear swelling in mice. The total flavonoids extracted by ultrasound had excellent biological activity. This establishes a foundation for further investigation into the potential medical value of D. genkwa .