Allergy-Preventive Effects of Chlorogenic Acid and Iridoid Derivatives from Flower Buds of Lonicera japonica

Allergy-preventive activity of flower buds of Lonicera japonica THUNB. was found in the 35% EtOH extract (LJ) using an in vivo assay, The assay system uses monitoring of a decrease in blood flow (BF) in the tail vein of mice subjected to sensitization with hen-egg white lysozyme (HEL). Bioassay-guided fractionation of the 35% EtOH extract led to isolation of chlorogenic acid (1) and three known iridoid derivatives, loganin (2), secoxyloganin (3)...