Electrodialysis with ultrafiltration membrane for efficient isolation of oxymatrine from simulated eluent of traditional Chinese medicine

Precise screening of bioactive molecules from traditional Chinese medicine (TCM) is increasingly important in the development of TCM as well as drug discovery, however, it remains a challenge due to the low separation efficiency of the target substance. In this study, a specially designed electrodialysis with ultrafiltration membrane (EDUF) was proposed to isolate positively charged oxymatrine from the simulated eluent of TCM that contains oxymatrine, proline and NaCl. Results indicate that the oxymatrine(+) can be efficiently isolated by EDUF with a low diffusion of proline (J(proline)). The current density was optimized at 10-15 mA/cm(2) to obtain a high recovery ratio of oxymatrine (R-oxymatrine) and low energy consumption. Moreover, a low feed concentration was recommended for the efficient isolation of oxymatrine due to a low J(proline) and high R-oxymatrine. Furthermore, the Roxymatrine can be increased to a high value of 97.0 % through a continuous operation of EDUF, and the purity of oxymatrine can be increased to 98.7 % by electrodialysis desalination. Therefore, the EDUF process exhibits a great potential in isolating positively charged oxymatrine from the simulated eluent of TCM.