Quality standard study on Pteris multifida
The quality control method and standard were established to control the quality of Pteris multifida in this paper. The tests of water content, total ash, acid-unsoluble ash and ethanol-soluble extractives of P. multifida were carried out according to the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1) . The TLC method was established by using rhoifolin as references, and a mixture of CHCl3 -MeOH-HAc (6: 1: 1) as the developing solvent system on GF254 thin layer plate. The contents of rhoifolin was determined by HPLC on a Diamonsil C18 (4.6 mm x 250 mm, 5 μm) column, using acetonitrile-water (containing 0.15% formic acid) (16: 84) as mobile phase at a flow rate of 1.0 mL x min(-1). The column temperature was 30 degrees C and the detection wave-length was 350 nm. As a result, pterosin C 3-O-β-D-glucosidede and the other constituents were well separated on TLC detected under the UV light at 254 nm . The methodology validation for the assay of rhoifolin presented that it was in good linear correlation in the ranges of 0.025 5-5.1 μg with the regression equations of Y = 1 092.4X + 9.503 5 (r = 0.999 8), and the average recoveries were 100.3% (RSD 1.3%). The content range of rhoifolin from 16 different batches of Pteris multifida was 0.08-5.06 mg x g(-1). The water content, total ash, acid-unsoluble ash and ethanol-soluble extractives of 16 samples varied in the ranges of 7.35% - 12.96%, 6.90% - 16.33%, 2.07% -11.38% and 13.29% -23.87%, respectively. The suggesting limes in the quality standard for water content, total ash, acid-unsoluble ash, ethanol-soluble extractives and rhoifolin content were ≤ 12% , ≤ 15% , ≤ 8.5% , ≥ 14% and ≥ 0.040%, respectively. The result proved that the established quality of control method was specific and accurate, which can be used for the quality control of P. multifida.