In vitro production and chemical characterization of St. John’s wort (Hypericum perforatum L. cv ‘New Stem’)

Abstract

Hypericum perforatum L. (St. John’s wort) is a traditional medicinal plant that has been used for the treatment of neurological disorders and depression. To investigate a large-scale in vitro growth system for St. John’s wort cv ‘New Stem’, six different culture systems, balloon type bubble bioreactor, temporary immersion bioreactor, temporary root zone immersion bioreactor, Erlenmeyer flask, large vessel with gelled medium under forced ventilation (LFV system), and Magenta vessel, were compared with greenhouse-grown plants for biomass production efficiency and accumulation of the selected bioactive molecules, hypericin, pseudohypericin, and hyperforin. After 25 days in culture, significantly more plant fresh mass was observed in a balloon type bubble (BB) bioreactor system than in other in vitro culture systems or in the greenhouse system. Plant dry mass was at a similar level in BB bioreactor, LFV system, and greenhouse. Chlorophylls a and b were highest in the leaves of plantlets grown in either large vessels with forced ventilation or temporary root zone immersion bioreactors. In general, levels of hypericin, pseudohypericin and hyperforin of the plantlets grown in the LFV system and levels of hypericin and pseudohypericin in the Magenta vessel were greater or similar to those in greenhouse-grown plants. Gelled medium (LFV system and Magenta vessel) had higher concentrations of hypericin and pseudohypericin than those grown in liquid medium. Together these results show that St. John’s wort can be efficiently produced in a variety of in vitro culture systems for aseptic production of bioactive compounds.