Characterization and anti-allergic effect of a polysaccharide from the flower buds of Lonicera japonica

► A polysaccharide (LJP-1) was isolated from Lonicera japonica and partially characterized. ► Oral administration of LJP-1 could inhibit ear thickness induced by picryl chloride (PC). ► LJP-1 treatment leads to substantial reductions in serum IgE, serum histamine and tissue TNF-α level. ► Treatment with LJP-1 may be effective for allergic contact dermatitis.