Biotransformation of furanocoumarins by Cunninghamella elegans

Biotransformation of Furanocoumarins; psoralen (1), bergapten (2), xanthotoxin (3) and imperatorin (4) was explored by Cunninghamella elegans NRRL 1392, revealing the metabolism of psoralen (1) and bergapten (2) into bergaptol (5), while xanthotoxin (3) and imperatorin (4) were converted into xanthotoxol (6). On the other hand unexpected conversion of xanthotoxin (3) into 3,4 dihydroxanthotoxin (7) occurred. The structure of the isolated pure metabolites was established using physical and spectroscopic techniques including, melting points, IR, ^1H NMR, ^13C NMR and mass spectroscopy.