Regioselective hydroxylation and glucosylation of flavanones with cultured plant cells of Eucalyptus perriniana. Cultured plant cells of Eucalyptus perriniana catalyzed reduction, regioselective hydroxylation, and regioselective glycosylation of flavanones. (2S)-Flavanone was converted into (2S)-flavan-4-ol, (2S)-flavan-4,7-diol, (2S)-flavan-7-ol, (2S)-flavan-7-yl glucoside, and (2S)-flavan-7-yl gentiobioside. The cells glucosylated (2S)-flavan-6-ol to (2S)-flavan-6-yl glucoside. (2S)-Flavan-2'-ol was transformed to (2S)-flavan-2',4-diol, (2S)-flavan-2',7-diol, (2S)-flavan-2'-yl glucoside. In addition, (2S)-flavan-4'-ol was transformed to (2S)-flavan-4,4'-diol, (2S)-flavan-4',7-diol, (2S)-flavan-4'-yl glucoside. 