Histochemistry of fleshy fruits polyphenols, cryostabilization and GMA embedding. Histotopochemical preservation and detection of polyphenols in fruits.

In the process of wax embedding the pulp of fleshy fruits is subsequently subjected to the action of the fixatives, the dehydrating agents (ethanol, acetone), the clearing agents (xilene) and finally to hot melted wax. Polar resin embedding is now proposed to preserve enzyme activity in semithin section for high resolution optical microscopy. The procedure has been tested on several fleshy fruits and at present we are working to confirm the preservation of lipids and waxy components, but also some water soluble components, notably polyphenolic substances, such as tannins. In fact lipids are easily extracted by apolar clearing solvents, but the dehydratig solutions (ethanol or acetone) may extract more polar components, or displace them from their original location.