Plant tissue cultures of Maclura pomifera showed a metabolite accumulation pattern which was both quantitatively and qualitatively different from that of the parent plant. Triterpenes and flavonoids were isolated from callus and cell cultures, however, xanthones and stilbenes, which have been reported in the whole plant, were not found. Among the flavonoids, flavones and flavanones were produced preferentially by the suspended cells, but with the prenyl substituents exclusively on ring A, while the isoflavones did not show the 3',4'-dihydroxyl substitution pattern found in the products isolated from fruits. A new prenylated 6'-deoxychalcone was also isolated from the callus and cell cultures.