Optimization of ultrasound assisted extraction method for polyphenols from Desmodium triquetrum (L.) DC. with response surface methodology (RSM) and in vitro determination of its antioxidant properties

The response surface method was used to study the ultrasonic extraction of traditional Chinese medicine Desmodium triquetrum (L.) DC. phenolic acid. By measuring the total phenolic content, the liquid/solid ratio, ultrasonic power, temperature, time and ethanol solubility were determined to be the significant influencing factors. The total phenolic content reached the highest value (30.3708 mg g(-1)) under the conditions of the liquid/solid ratio 30%, ultrasonic power 160 w, temperature 40 degrees C, time 20 min, and ethanol solubility 60%, compared with the traditional boiling method. The total phenolic content was improved, and it was close to the predicted value (29.6548 mg g(-1)), which proves that the scheme is feasible. After testing, the phenolic acid extracted under these conditions has a good antioxidation effect. The study suggests that ultrasonic extraction methods have the potential to extract antioxidants from traditional Chinese medicines. Also, the influence parameters affecting the process can be further optimized for industrial production.