Abstract
The effect of different tissue prehandling methods on the phenolic content of willow
bark, leaves, and twigs was studied. The phenolics were extracted at room temperature,
purified, and analyzed by high resolution capillary gas chromatography. Neither oven-drying
at a low temperature nor room-drying of fresh leaves and oven-drying of bark produced
any qualitative changes in the glucoside composition and only a minor binding effect
was seen on the amounts of each glucoside. On the other hand, oven-drying of the intact
long twigs and room-drying of the bark are prehandling methods to avoid. Freeze-drying
or immediate analysis of frozen leaves lowered the total amount of glucosides and
caused considerable qualitative changes to the glucoside composition. 80% acetone
was found to be slightly more effective and gentle extraction solvent for all glucosides
compared with methanol.
