Study On Extraction, Purification And Antibacterial Activity Of Osthole From Radix Angelica Pubescens

The osthole, which is the major antibacterial component of Radix AngelicaPubescens, was qualitative and quantitative detected by High PerformanceLiquid Chromatography. Microwave-assisted extraction and cellulase-assistedextraction were used to extract osthole; macroporous resin was used to purifyosthole. The antibacterial activity of purified osthole was also determined bybacteriostatic test, so as to providing theoretical basis and practical guiding forexploiting and utilizing osthole of Radix Angelica Pubescens to beantibacterial drugs. The main results are as follows:1.The optimal parameters for the extraction conditions of osthole weredetermined by single factor and response surface methodology. The optimalextraction conditions of microwave-assisted extraction were as follows: the ratio ofliquid to solid20:1mL/g, extraction time1.0h, extraction temperature35℃andmicrowave power330W. The yield of osthole was1.03%.The optimal extractionconditions of cellulase-assisted extraction were as follows: pH5.0, temperature50℃, time60min and the amount of cellulose3%. The yield of osthole was0.926%under this conditions.2. The adsorption and desorption properties were studied to choose the optimalmacroporous resin and X-5macroporous resin was chosen to be the optimal, the optimized parameters for the purification of osthole were as follows: the content ofosthole was0.345mg/mL, the flow rate was1BV/h, The eluent was80%ethanol, the flow rate was1BV/h and the volume was29BV. The purity ofosthole was reached to23.13%after X-5macroporous resins.3.The bacteriostatic test showed that: the purified osthole had certainantibacterial activities on Staphylococcus.epidermidis, Escherichia.coli,S.agalactiae and Staphylococcus.arueus. And it had stronger antibacterialactivities than the crude extraction of Radix Angelica Pubescens. The MICvalues of Escherichia coli was12.5mg/mL.