Cytotoxic Activity of β -Caryophyllene Oxide Isolated from Jeju Guava (Psidium cattleianum Sabine) Leaf

 β -caryophyllene oxide was isolated from the leaf of the Jeju guava (Psidium cattleianum Sabine) for the first time in this study. The chemical structure was confirmed with the help of various spectroscopic analyses, including NMR data, by comparison to that of the published data. An MTT assay was conducted against several cancer cell lines t o resolve an ongoing controversy regarding the cytotoxic effects of β-caryophyllene oxide. β-caryophyllene oxide evidenced potent cytotoxic activity against HepG2, AGS, HeLa, SNU-1, and SNU-16 cells, with IC 50 values of 3.95, 12.6, 13.55, 16.79, and 27.39 μM, respectively. The results also showed that β-caryophyllene oxide evidenced cytotoxicity in both a dose-dependent and time-dependent manner.