The Optimal Extracting Conditions for Rotundine-rich Extract fromStephania Glabra Tubers

Introduction: Stephania glabra (S. glabra) is a medicinal plant from the Menispermaceae family, traditionally used to treat various ailments. Its tubers contain alkaloids, particularly rotundine, which have sedative, analgesic, and cardioprotective properties with minimal toxicity. Optimizing rotundine extraction is crucial for its pharmaceutical applications. The Response Surface Methodology (RSM), particularly the Box-Behnken Design (BBD), is an effective approach to refining extraction conditions by reducing experiments, minimizing solvent use, and improving efficiency Methods: The RSM with BBD design was applied to optimize the extracting conditions for obtaining a rotundine-rich extract from Stephania glabra tubers using a predictive modeling approach with four independent factors (temperature, methanol concentration, extraction time, and liquidsolid ratio). Results: The proposed model was experimentally validated, demonstrating a high degree of accuracy, with predicted and actual rotundine contents showing strong agreement with p-value < 0.0001, model, adjusted, and predicted R2 above 0.90. A systematic evaluation of key extraction parameters, including temperature (55°C), methanol concentration (67%), extraction time (154 minutes), and liquid/solid ratio (30/1), was conducted to maximize rotundine yield. The findings indicate that the optimized extraction process consistently yielded extracts with more than 15%. Discussion: RSM optimization effectively maximized rotundine yield with minimal resource use. The model’s accuracy and key factors—temperature and methanol concentration—align with previous studies, offering a more efficient approach for rotundine extraction and potential use in other medicinal plants. Conclusion: This research establishes a scientific basis for efficient rotundine extraction and its pharmaceutical applications. The validated predictive model for optimizing extraction from Stephania glabra tubers demonstrated strong accuracy, reinforcing its reliability and practical value in the medicinal field.