ANTHRAQUINONES PRODUCTION IN AERIAL PARTS-DERIVED CALLUS OF RUBIA TINCTORUM L.

Callus cultures were developed from the aerial parts of Rubia tinctorum L. on MS medium
containing 6-benzylaminopurine and 1-naphthaleneacetic acid. The changes in callus weight
and anthraquinones content were followed between week 1 and 6. Anthraquinones content was
monitored by HPLC. The linear increase in fresh weight was found to be parallel to the
anthraquinones production. Effect of medium pH, incubation temperature and growth
regulators on callus growth and anthraquinones content was studied and optimised. pH 7.5 and
temperature of 30° were found optimum for the callus growth. 6-Benzylaminopurine (0.5 mg/L)
and 1-naphthaleneacetic acid (2.0 mg/L) were found the most appropriate growth regulators.
The callus ethanolic extract showed the same picture on TLC as that of the roots. The
anthraquinones alizarin (1), lucidin--ethyl ether (2), 1-hydroxy-2-hydroxymethylantraquinone-
3-O- -glucoside (3) and lucidin primeveroside (4) in addition to other four minor
anthraquinone spots were found to be produced by these cultures. The four isolated compounds
(1-4) were identified by spectral analysis (UV, IR and MS) as well as comparison with authentic
samples. Aerial parts, roots and the callus were analysed for their anthraquinones content. The
anthraquinones content of callus extract was about 91% and eighteen fold of the roots and
aerial parts extract respectively.