Cancer chemopreventive activity of euglobal-G1 from leaves of Eucalyptus grandis

In the course of our continuing search for novel cancer chemopreventive agents from natural sources, several kinds of Eucalyptus plants were screened. Consequently, the phlorogrucinol–monoterpene derivative, euglobal-G1 (EG-1), was obtained from the leaves of Eucalyptus grandis as an active constituent. EG-1 exhibited the remarkable inhibitory effect on two-stage carcinogenesis test of mouse skin tumors induced by 7,12-dimethylbenz[a]anthracene (DMBA) as an initiator and fumonisin-B1, which has been known as one of mycotoxins produced by Fusarium monifliforme, as a promoter. Further, EG-1 exhibited potent anti-tumor-promoting activity on two-stage carcinogenesis test of mouse pulmonary tumor using 4-nitroquinoline-N-oxide (4-NQO) as an initiator and glycerol as a promoter.