The bioconversion process of deoxypodophyllotoxin with Linum flavum cell cultures

The in vitro cell suspension culture of Linum flavum is able to convert high amounts of the 2,7'-cyclolignan deoxypodophyllotoxin into 6-methoxypodophyllotoxin 7- O-glucoside. We studied this conversion in detail by monitoring the intermediates and side-products after feeding different concentrations of deoxypodophyllotoxin. At a low concentration (0.1 mM) deoxypodophyllotoxin is rapidly converted into 6-methoxypodophyllotoxin 7- O-glucoside, 6-methoxypodophyllotoxin and traces of beta-peltatin and podophyllotoxin. The feeding of 0.5 and 2.0 mM also shows a rapid conversion into 6-methoxypodophyllotoxin 7- O-glucoside, but a delayed formation of 6-methoxypodophyllotoxin and beta-peltatin. By using different extraction methods we delivered proof in favour of the hypothesis that a part of the deoxypodophyllotoxin after uptake is temporarily stored as beta-peltatin glucoside.