Plant Science 166 (2004) 229–236 Enhancing the production of cinnamyl glycosides in compact callus aggregate cultures of Rhodiola rosea by biotransformation of cinnamyl alcohol Zsuzsanna György a,∗ , Ari Tolonen b , Minna Pakonen c , Peter Neubauer a , Anja Hohtola c a Bioprocess Engineering Laboratory, Department of Process and Environmental Engineering, University of Oulu, P.O. Box 4300, 90014 Oulu, Finland b Department of Chemistry, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland c Department of Biology, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland Received 13 June 2003; received in revised form 25 August 2003; accepted 11 September 2003 Abstract Compact callus aggregates (CCA) of Rhodiola rosea were established. The growth curve of CCA culture was determined. No secondary compounds are produced in callus. Cinnamyl alcohol was added to the media in several concentrations between 0.05 and 5 mM in order to stimulate the production of cinnamyl glycosides. The optimal concentration of the precursor was determined. The consumption of cinnamyl alcohol and the production of cinnamyl glycosides were followed by daily sampling. The chemical analyses of the samples were performed by HPLC/MS. Among the cinnamyl glycosides rosin was produced in high amounts. A three to sixfold rosin content was achieved in the treated calli comparing to the content of wild growing plants. Rosavin was produced in traces only. © 2003 Elsevier Ireland Ltd. All rights reserved. Keywords: Rhodiola rosea; Cinnamyl alcohol; Cinnamyl glycosides; Compact callus aggregates 1. Introduction Rhodiola rosea (rose root) is a medicinal plant mainly used in Asia and Eastern Europe. It is a member of the Crassulaceae family, a perennial herbaceous plant growing in Northern areas. The rhizome contains secondary metabo- lites among which the most important ones are tyrosol and its glucoside salidroside, and the cinnamyl alcohol glyco- sides rosin, rosavin, rosarin (Fig. 1). There are more than 200 Rhodiola species but cinnamyl alcohol glycosides, in- cluding rosavin, are found only in R. rosea. Other Rhodi- ola species contain only salidroside [1]. Russian researchers have described this plant as an adaptogenic since it offers generalized resistance to physical, chemical and biological stressors. Most commonly R. rosea can be administered as an alcohol-based extract for the asthenic condition due to overwork. The symptoms are poor appetite, sleep distur- bances, declining work performance, irritability, hyperten- sion, headaches and fatigue [2]. Furthermore cell culture, ∗ Corresponding author. Tel.: +358-8-553-2361; fax: +358-8-553-2304. E-mail address: zsuzsanna.gyorgy@oulu.fi (Z. György). animal and human studies revealed anticancer, antioxidant, antistress, immune enhancing and sexually stimulating ef- fects [3]. Field cultivation of this plant takes several years to obtain a satisfactory content of the pharmacologically interesting compounds [4]. An alternative source of these compounds is the production in cell cultures. However, in callus and in vitro grown plants no salidroside or rosavin was found [5]. The phenylpropanoids are prob- ably transformed to p-hydroxyrosine (triandrin) by phenyl- hydroxylases [4]. Furmanova et al. added trans-cinnamyl alcohol in 2.5 mM concentration to the media and reported 90% of it to be transformed into several products, but only rosavin was identified [6]. In most cases, some level of differentiation is needed for the biosynthesis of secondary metabolites. In case of Rhodi- ola sachalinensis compact callus aggregates (CCA) are used instead of cell suspensions. Compact callus aggregates are spherical, smooth surfaced clumps displaying some level of cellular or tissue differentiation [7]. The aim of this work was to examine the possibility of sti- mulating the production of cinnamyl glycosides in R. rosea compact callus aggregates by adding cinnamyl alcohol. 0168-9452/$ – see front matter © 2003 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.plantsci.2003.09.011