Identification of an anticancer compound against HT-29 cells from Phellinus linteus grown on germinated brown rice.

ABSTRACT

OBJECTIVE: To isolate and identify the anticancer compound against proliferation of human colon cancer cells from ethyl acetate (EtOAc) extract of Phellinus linteus grown on germinated brown rice (PB). METHODS: EtOAc extract of PB was partitioned with n-hexane, EtOAc, and water-saturated n-butanol. Anticancer compound of n-hexane layer was isolated and identified by HPLC and NMR, respectively. Cytotoxicity against HT-29 cells was tested by SRB assay. RESULTS: The n-hexane layer obtained after solvent fractionation of PB EtOAc extracts showed a potent anticancer activity against the HT-29 cell line. Atractylenolide I, a eudesmane-type sesquiterpene lactone, a major anticancer substance of PB, was isolated from the n-hexane layer by silica gel column chromatography and preparative-HPLC. This structure was elucidated by one- and two-dimensional NMR spectroscopic data. Atractylenolide I has not been reported in mushrooms or rice as of yet. The isolated compound dose-dependently inhibited the growth of HT-29 human colon cancer cells. CONCLUSIONS: Atractylenolide I might contribute to the anticancer effect of PB.