Bioactive homoisoflavones from Vietnamese coriander or pak pai (Polygonatum odoratum)

The roots of Polygonatum odoratum were screened for compounds which induce apoptosis in breast cancer cell lines. The powdered roots were extracted with methanol and ethyl acetate. The ethyl acetate fraction was then subjected to bioassay directed fractionation using silica gel column chromatography. Bcl-2 protein, a regulator of apoptosis, was assessed by immunoblot. The active fraction was eluted with 30:1 CHCl₃/CH₃OH and was rechromatographed on a second silica gel column. Elution with 20:80 hexanes/chloroform yielded the active fraction which was purified using semipreparative HPLC. Two compounds were identified. These include 2,3-dihydro-3-[(15-hydroxyphenyl)methyl]-5,7-dihydroxy-6-methyl-8-methoxy-4H-1- benzopyran-4-one and 2,3-dihydro-3-[(15-hydroxyphenyl)-methyl]-5,7-dihydroxy-6,8-dimethyl-4H-1- benzopyran-4-one.