[Objective] The aim was to investigate the influence of different size of ground Cyanotis arachnoidea C.B.Clarke particles on the release of β-ecdysone.[Method] The content of β-ecdysone extracted from Cyanotis arachnoidea powders of different sizes was detected through HPLC,under the chromatographic conditions：GRACE ODS C18 column（250 mm × 4.6 mm,5 μm）,mobile phase methanol：water= 40：60（V/V）,column temperature 26 ℃,flow rate 1.0 ml/min and detection wavelength 248 nm.[Result] The extracted β-ecdysone from ultra-fine Cyanotis arachnoidea powder（particle size 10,30 and 50 μm） was as more than two folds as common powder（particle size 180 μm）.[Conclusion] The β-ecdysone in ultra-fine powder of Cyanotis arachnoidea was more easily soluble in methanol.The extraction rate of β-ecdysone was significantly higher than that of common powder.The result showed that the technology of ultra-fine pulverization markedly improved the dissolution of the β-ecdysone for increasing the cell breakage rate,and then the active ingredients could be extracted more easily.
