Syringin (Syr)

Syringin is a natural chemical compound first isolated from the bark of lilac (Syringa vulgaris) by Meillet in 1841. It has since been found to be distributed widely throughout many types of plants. It is also called eleutheroside B, and is found in Eleutherococcus senticosus (Siberian ginseng). It is also found in dandelion coffee. Chemically, it is the glucoside of sinapyl alcohol. Syringin was found to possess immunomodulatory activity by which it inhibited the in-vitro immunohaemolysis of antibody-coated sheep erythrocytes by guinea-pig serum through suppression of C3-convertase of the classical complement. Its in-vitro and in-vivo activity on tumour necrosis factor (TNF)-alpha and nitric oxide (NO) production, CD4+ T cell and CD8+ cytotoxic T cell (CTLL-2) proliferation, and croton oil-, arachidonic acid- and fluorescein-isothiocynate (FITC)-induced mouse ear oedema model.