Arnica montana L. cell suspension culture as a biotechnological approach for the production of bioactive secondary metabolites

Arnica montana L. is a medicinal plant with traditional use to treat sprains, bruises, rheumatic and muscular aches based on the anti-inflammatory properties of sesquiterpene lactones (SL), mainly esters of helenalin and dihydrohelenalin. Overexploitation has led to conservation actions in the majority of European countries, involving in vitro cultivation techniques as a sustainable alternative. Cell suspension cultures of A. montana have not been reported extensively, although a sustainable biotechnological process in bioreactors for production of the active plant secondary metabolites is of great interest for industry. The starting plant material consisted of seeds, collected from wild populations in the Romanian Eastern Carpathians. Germination in aseptic environment lead to sterile plantlets for the micropropagation process. Leaf fragments of about 1 cm2 were placed on several medium variants – MS medium supplemented with different amount of 2,4-dichlorophenoxyacetic acid and benzylaminopurine for callus induction. First qualitative results show that suspension cultures from the obtained calli in small scale single-use bioreactors have been successfully established. Due to small biomass amounts, common HPLC and HPTLC methods from the Ph Eur Monograph on Arnica for SL, flavonoids and phenolic acids using HPLC and HPTLC had to be optimized to very low sample amounts. Quantitative assessment of the desired secondary metabolites is under way in parallel to the continuous culturing process. The final aim of the study is to show differences in secondary metabolite content in plant material from the field, callus and cell suspensions