Anti-inflammatory triterpenes from Pistacia terebinthus galls.

From the galls of Pistacia terebinthus we obtained an extract that proved to be effective against chronic and acute inflammation. Now we report on the isolation and identification of three triterpenes: two tirucallane-type lanostanoids and one oleanane, which we have identified as masticadienonic acid (1), masticadienolic acid (2), and morolic acid (3), respectively. All of them showed effectiveness on the mouse ear inflammation induced by repeated applications of 12-O-tetradecanoylphorbol 13-acetate and on the phospholipase A2-induced foot paw edema. The pharmacological activity of the compounds was ratified by a histological study of the ear samples. In addition, they inhibited leukotriene B4 production in rat polymorphonuclear leukocytes stimulated with calcium ionophore A 23187.