Study on optimization of ultrasonic extraction processing and in vitro antioxidant activity of Fructus Tribuli polysaccharides

Key Points

• This research aims to optimize the extraction process of Fructus Tribuli polysaccharides and evaluate their antioxidant activity.
• Utilized response surface methodology to optimize ultrasonic extraction factors: liquid-to-material ratio, ultrasonic time, temperature, and ethanol concentration.
• Determined the sugar composition of the extracted polysaccharides using HPAEC-PAD method.
• Assessed the in vitro antioxidant activity against DPPH, ABTS, and hydroxyl radicals.
• Optimal extraction conditions were a liquid-to-material ratio of 20:1, ultrasonic time of 51 minutes, ultrasonic temperature of 62°C, and ethanol concentration of 95%, yielding a polysaccharide extraction rate of 2.182%.
• The sugar composition included fucose, rhamnose, arabinose, galactose, glucose, xylose, mannose, galacturonic acid, and glucuronic acid in specific proportions.
• At a concentration of 2.5 mg/mL, the extracted polysaccharides exhibited significant antioxidant activity, with DPPH, ABTS, and hydroxyl radical scavenging rates of 67.8%, 88.9%, and 90.7% respectively.