Enhanced Terpenoids Production of Elicited Hairy Root Cultures of Scutellaria bornmuelleri

Abstract

Scutellaria bornmuelleri is recognized as a medicinal plant and a rich source of terpenoids. Hairy Root Cultures (HRCs) along with elicitation of in vitro cultures have been widely considered in order to produce important secondary metabolites such as terpenoids. In the present study, S. bornmuelleri HRCs were established by transformation of stem explants with Agrobacterium rhizogenes strain A4. The effect of different concentrations of sucrose on transgenic root induction and biomass production were investigated. The production and accumulation of terpenoids in HRCs elicited with chitosan (CS), methyl jasmonate (MeJA) and β-cyclodextrin (β-CD) was evaluated using Gas chromatography/mass spectrometry (GC/MS). Among various concentrations of sucrose, half-strength Murashige and Skoog (MS) medium supplemented with 2.5% sucrose resulted in significant increase in transformation frequency and maximum root biomass production. The highest sesquiterpene production was observed in HRCs elicited with 100 mg L -1 CS. However, the highest monoterpene accumulation was occurred in HRCs treated with 100 µM MeJA. Among the combined treatments, the highest sesquiterpene and monoterpene yield was achieved by 0.7 and 7 mM β-CD plus MeJA as well as 50 and 100 mg L -1 CS plus MeJA, respectively. To the best of our knowledge, the results of this study for the first time suggested that eliciting HRCs can be an effective method to accumulate sesquiterpenes in large scale cultures of S. bornmuelleri HRs in bioreactor.