Optimization of the separation and purification process for iridoid glycosides from Lamioplomisrotata

Objective To obtain iridoid glycosides with relatively high purity by the optimization of the preparation process of iridoid glycosides from Lamioplomisrotata. Methods Used methanol-water mobile phase with gradient run to set up an HPLC method and achieved the best separation of each composition. Recorded and calculated statistics for its three-dimensional absorption spectrum combined with UV visible wavelength scanning to analyze the characteristics of the impurities, which have affected the purity of previous preparations of iridoid glycosides from Lamioplomisrotata. To optimize the process, a macroporous adsorptive resin chromatographic column and a polyamide chromatographic column were used on the basis of characteristics of the impurities. A real time UV visible wavelength scan was applied to monitor the effluent components of each column to remove the impurities. Merged the ethanol elution which had the characteristic absorption at 235 nm and smaller absorptions at other wavelengths. The target solutions were cryodesiccated. Compared the differences of the iridoid glycoside compositions at equal concentrations before and after the experiment by HPLC. Results The contents of iridoid glycosides from Lamioplomisrotata before and after the purification process were 69.06% and 90.60% respectively. The yield was 16.70% (use the quality of the water extract as a reference).The transfer rate of iridoid glycosides was 74.72% (relative to the quality of water extract of total iridoid glycosides). Compared with the previous preparation technology, the content was increased to 21.54%. Conclusion The optimization process was simple and practicable with high efficiency, which made a significant improvement in the purity of the iridoid glycosides from Lamioplomisrotata.