Objective    To screen the Chinese herbs with high affinity for lipid A and extract the anti-lipopolysaccharide (LPS) compound from densefruit pittany root-bark (DPR).     Methods    Forty-two kinds of aqueous extracts of traditional Chinese medicine were screened to determine their binding to lipid A by the biosensor technology. The chemical components with high affinity for lipid A were gotten by macroporous adsorptive resins

solvent extraction

polyamide laminar analysis and high performance liquid chromatogram (HPLC) from DPR. The neutralization of HPLC products DPR1-3 for LPS （0.1 ng/ml） was detected by kinetic turbidimetric limulus test. The release of TNF-α and IL-6 in RAW264.7 cells after exposure to LPS (100 ng/ml) were detected by ELISA.     Results    Eight kinds of aqueous extracts including DPR displayed high affinity for lipid A (RU100 arc/s). Three chemical components DPR1-3 with high affinity for lipid A were gotten. DPR-2 neutralized LPS and inhibited the release of  TNF-α and IL-6 in LPS-induced RAW264.7 cells in a dose-dependent manner.     Conclusion    Eight herbs possess the components with high affinity for lipid A. DPR-2

extracted from DPR

shows anti-LPS activity probably by binding lipid A and neutralizing LPS.