Horse Chestnut Extraction

I would like to make an extraction of horse chestnut seed. Should I use the seed as whole, or only the inside of it? I would like to get the aescin part, and low level of aesculin (which should be toxic). I would like to use it e.g. in bath.

Aescin is found in seeds, husk and leaves, while aesculin and its aglycone, aesculetin, are found in the leaves and seeds, but not the husk. Using the husks only would be the simplest approach.
There is a patent on the extraction of aescin from the seeds using chemical methods:
www.freshpatents.com/Simple-process-for-obtaining-beta-aescin-from-indian-horse-chesnut--aesculus-indica--dt20060209ptan20060030697.php?type=description
There is a lot of useful information about aescin and how it is extracted in the patent.