Abstract
Phenethyl alcohol was galactosylated by the β-galactosidase of Escherichia coli using lactose as the galactosyl donor. When 4 kg of phenethyl alcohol and 60 kg lactose in 10 mM potassium phos-phate buffer (pH 7.0) were incubated for 3 h at 40°C in the presence of 10 U/mL β -galactosidase, 2.8 kg of phenethylgalactoside was obtained in a 30.2% yield based on the phenethyl alcohol added. This product was water-soluble and had no perfume. It was identified as phenethyl β-D-galactopyranoside (PEGaI) by hydrolysis with α/β-galactosidase, FAB-mass and 1H-, 13C-NMR spectroscopies, respectively. PEGaI increased the floral aroma in rose flowers more strongly than phenethyl α -D-glucopyranoside (PEGIc).
