Objective: To establish a method for determination of verbascoside and isoacteoside in Rehmanniae Radix simultaneously by HPLC

and to compare content changes of isoacteoside in Rehmanniae Radix and its processed products.Method: Contents of verbascoside and isoacteoside were determined by HPLC

Waters-Symmetry ShieldTM RP18 column (4.6 mm×250 mm

5 μm) was employed with a mobile phase of acetonitrile-0.1% acetic acid solution (18:82)

flow rate of 1 mL · min-1

column temperature at 30℃

detection wavelength of 334 nm and injection volume of 20 μL.Result: There was no isoacteoside in fresh Rehmanniae Radix temporarily

but through a certain temperature and time of processing

isoacteoside can be determined.In Rehmanniae Radix samples steamed at different times

the content change of verbascoside and isoacteoside was a dynamic change process

and the steaming time had a great effect on the content of isoacteoside in Rehmanniae Radix.Baked at a certain temperature

it can produce isoacteoside in fresh Rehmanniae Radix

but in the different time periods

the content of isoacteoside did not change obviously.Verbascoside and isoacteoside could be transformed into each other under certain conditions.Conclusion: Production of isoacteoside in Rehmanniae Radix is partly from the transformation of verbascoside;isoacteoside can be considered as a one of the quality control indexes of Rehmanniae Radix Praeparata.