Production of indole alkaloids in hairy root cultures of Catharanthus roseus L. and their antimicrobial activity

Transgenic hairy roots of Catharanthus roseus L. were recovered.
• Accumulation of vincristine, catharanthine and vinblastine were determined in the transgenic hairy roots.
• The antimicrobial activity of the transgenic hairy roots was confirmed.

Agrobacterium rhizogenes-mediated transformation of Catharanthus roseus, an important medicinal plant that produces the powerful anticancer drug vincristine, was achieved by infecting stem and leaf explants with strain K599 harboring p35SGFPGUS + plasmid. Leaf explants induced hairy roots at a higher frequency than stem explants when infected with the Agrobacterium strain. The root initials on the wounded leaf explants proliferated vigorously and elongated more rapidly when they were segmented and subcultured on either half-MS or full-strength MS medium. The molecular evidence of HPTII, GUS and GFP genes integration was confirmed by PCR amplification. Moreover, the proliferated transgenic roots were evaluated for growth, morphology, alkaloid content and its antimicrobial activity. Growth of the hairy roots was undertaken by measuring root growth unit after culturing hairy root segments in either half-MS or full-strength MS liquid medium and determination of the fresh weight during the time-course of the experiment in shake flask cultures. The maximum biomass and accumulation of the antimicrobial activity were reordered when the hairy roots were cultured in liquid full-strength MS. In the present study, we have confirmed the accumulation of alkaloids (i.e. vinblastine, vincristine and catharanthine) in the transgenic hairy root which also secreted in the liquid culture medium.