The claims that could be made by such as Paracelsus (9)
I believe the answer is:
Here is my best explanation:
'such as paracelsus' is the definition.
(I've seen this before)
'the claims that could be' is the wordplay.
'that could be' indicates anagramming the letters.
'theclaims' anagrammed gives 'ALCHEMIST'.
'made by' is the link.
(Other definitions for alchemist that I've seen before include "St Michael in role of one turning base metal into gold", "Seeker after gold", "... seeker after stone", "magician", "His hope to discover elixir of life", "St Michael (anag)", "One seeking to produce gold, elixirs etc", "Early experimenter", "seeker for gold" and "One tried to turn ordinary metal into gold".)