Application of Accelerated Solvent Extraction(ASE) for the Extraction of Compounds in Fructus Xanthii / 中药新药与临床药理

Objective To establish a method for extracting compounds in Fructus Xanthii by accelerated solvent extraction(ASE),and to simultaneously determine the compounds by GC-MS.Methods The extraction was performed by ASE in which the conditions were optimized by orthogonal test,then the compounds in different extracts with different polarity were determined by GC-MS.Results The optimized conditions of ASE for compounds in Xanthium sibiricum fruits were as follows: petroleum ether,ethyl acetate and methanol as extracting solvent in turn in 33 mL extracting tube and the volume of solvent being 65 mL;6 g sample,9 MPa of extracting pressure,90 ℃of extracting temperature,5 min of extracting time,two cycles and one time for each extraction.The GC-MS conditions were as follows: 1 ?L extract was analysed by GC-MS(Shimadzu Model QP-2010) instrument fitted with a flame ionisation detector,separation was achieved on a DB-5ms,DB-17ms and DB-WAX column(J&W Scientific,30 m,0.25 ?m id film thickness,1.4 ?m,USA) respectively,the column temperature was maintained at 60 ℃for 3 min and increased to 250 ℃,the scanning range was from m/z 40 to m/z 700(scanning interval: 0.5 s),and the compounds were identified by searching NIST and Wiley registry of mass spectral data.Conclusion There are 61 compounds found in the petroleum ether extract and in which 48 are identified,22 in the ethyl acetate extract and 18 identified,as well as 34 in the methanol extract and 29 identified with the methods of optimized ASE combined with GC-MS.

Antioxidant Compounds and Radical Scavenging Property of Fructus Xanthii / 中药新药与临床药理

Objective To isolate and purify the antioxidant compounds from fructus xanthii and to study their antioxidant activity.Methods Compounds were isolated by repeated silica gel,macroreticular resin Diaion HP-20 and Sephadex LH-20 column chromatography and their antioxidant property was determined by scavenging activity to DPPH and ?OH.Results Five antioxidant compounds were isolated from the ethyl acetate extracts of Xanthium sibiricum fruits and their structures were identified as 5,7,3',4'-tetramethoxyisoflavone,myricetin-3'-methyl ether,falcalindiol,1,8-heptadecadiene-4,6-diyne-3,10-diol and 3,4-dihydroxybenzoic acid.Among them,3,4-dihydroxybenzoic acid had the highest radical scavenging activity.Conclusion All above 5 compounds have high antioxidant activities,and antioxidant activity of 3,4-dihydroxybenzoic acid is the highest.