GERANYL -O-ALPHA-L-ARABINOPYRANOSYL-BETA-D-GLUCOPYRANOSIDE ISOLATED AS AN AROMA PRECURSOR FROM LEAVES OF A GREEN TEA CULTIVAR

A new glycosidic aroma precursor was isolated from green tea leaves (C amellia sinensis var. sinensis cv. Yabukita) along with the known prim everosides of cis-linalool 3,6-oxide, linalool and geraniol. These gly cosides mere separated by chromatographic isolation on Amberlite XAD-2 , ODS hash chromatography, and finally HPLC. The chemical structure of the new unknown glycoside was confirmed as geranyl -O-alpha-L-arabino pyranosyl-beta-D-glucopyranoside (geranyl beta-vicianoside) by spectro metric analyses and by an enzymatic hydrolysis with glycosidase follow ed by GC-MS and HPLC anslyses. Moreover the vicianoside was hydrolyzed with acetone powder obtained from fresh tea leaves to generate the sa me compounds, suggesting this glycoside to be a tea aroma precursor.