Biotransformation of dihydroresveratrol by crude Momordica charantia peroxidase provided six new acyclicbis[bibenzyls] 1-6. Their structures were established on the basis of NMR and MS analyses as C-C, C-O-C, and C-CH(2)-C dimers of dihydroresveratrol. Compounds 1-6 were tested for antiproliferative activity against human prostate cancer PC3 cell line in vitro, and 2 and 6 were found to be more potent