Ultrafiltration LC-ESI-MS~n Screening Of Anti-inflammatory Chemical Components From Selected Chinese Medicinal Herbs

Five flavonoids(puerarin, daidzin, daidzein, 3′-hydroxy-puerarin and 3′-methoxypuerarin) were successfully isolated and purified from ethyl acetate extract of Pueraria lobata by high performance current-counter chromatography(HPCCC) using the solvent system hexane/ ethyl acetate/ n-butanol/ ethanol/ water(0.5:2:1:0.5:3.5), and the purity of the five compounds detemined by high performance liquid chromatography(HPLC) were all over 90%. The five purified compounds were identified by the refenrences about the compouds, the congruent retention times, the data of liquid chromatography electrospray ionisation tandem mass spectrometry(LC-ESI-MSn) and the nuclear magnetic resonance(NMR) with those of the authentic standards.In vitro Matrix metalloproteinases-2(MMP-2), Phosphodiesterase-4(PDE-4) and 5-lipoxygenase(5-LOX) inhibition assays and ultrafiltration LC-ESI-MSn were combined to screen the enzyme inhibitors from S.divaricata, P. lobata, S. glabrae, C. tinctorius and S. china.Results showed that, extracts of both S.divaricata and P. lobata were identified as strong MMP-2 inhibitors, and the major components 4′-O-b-D-glucosyl-5-Omethylvisamminoland, puerarin, daidzin, daidzein, prim-glucosylcimifugin, cimifugin and sec-O-glucosylhamaudol were also MMP-2 inhibitors in both assays; the extract of C. tinctorius was found to be the strongest inhibitor of PDE-4 among the four herbs, and the major components 4′-O-b-D-glucosyl-5-O-methylvisamminoland, primglucosylcimifugin, astilbin, cimifugin, safflower yellow B(SYB), puerarin, Hydroxysafflor yellow A(HSYA), daidzin, sec-O-glucosylhamaudol, daidzein, isoastilbin, engelitin, isoengelitin were also PDE-4 inhibitors in both assays, 3′-hydroxy-puerarin, 3′-methoxy-puerarin and resveratrol were found to have low inhibition activity and 4′-O-b-D-glucosyl-5-O-methylvisamminoland was found to be the strongest inhibitor towards PDE-4; extracts of all the five herbs were found to be the inhibitors of 5-LOX, and S.divaricata was found to be the strongest, and the major components SYB, HSYA, daidzin, resveratrol, daidzein, 3′-hydroxy-puerarin, sec-O-glucosylhamaudol, astilbin, prim--glucosylcimifugin, 4′-O-b-D-glucosyl-5-O-methylvisamminoland, engelitin, puerarin, isoastilbin, cimifugin, isoengelitin were also 5-LOX inhibitors in both assays.