Abstract

Conditions for co-culturing the cell suspensions of Catharanthus roseus, Rauwolfia serpentina and Vinca major in shake flask and bioreactor are described here for the possible complementation of the terpenoid indole alkaloid pathway operating in them. Catharanthus + Rauwolfia or Catharanthus + Vinca cell combinations could be reared on a Murashige and Skoog medium containing 2.0 mg L^-1 naphthalene acetic acid (NAA) and 0.2 mg L^-1 kinetin (Kn). A 20- and 40-fold increment in the biomass of these co-cultures was achieved within 30 days in a stirred tank bioreactor. Thin layer chromatography (TLC) of the alkaloid extracts of co-cultures of Rauwolfia + Catharanthus showed the presence of two novel compounds (RF1 and RF2) upon staining with Dragendroff’s reagent. Proton nuclear magnetic resonance (¹HNMR), electrospray ionization mass spectrometry (ESI-MS) and ultraviolet (UV) spectral analysis data of these compounds suggested an indole alkaloid identity. Out of these two alkaloids, compound RF1 was found to possess strong antioxidant potential.

Key words: Catharanthus roseus, Rauwolfia serpentina, Vinca major, co-culture, terpenoid indole alkaloids, pathway complementation.