Objective:To compare the powder properties between common powder and micropowders of Angelica to provide experimental evidence for the superfine grinding application.Method:Morphology structure

hygroscopic property

liquidity

surface area and porosity of Angelica powders were investigated;the contents and the dissolution of ferulic acid of Angelica powders were determined by HPLC.Result: With the decreasing of particle size of powders

the surface area

pore volume and moisture increased

and the liquidity decreased;the contents of ferulic acid from four Angelica powders were in the order of: common powder > ultrafine powder I > ultrafine powder II > ultrafine powder III;but with the crushing level increased

dissolution rate and the total dissolution of the ultrafine powder II was higher than levels of particle size in other angelica powder.Conclusion: An appropriate degree of micronization is helpful for the dissolution of the active components in Angelica.