Elicitation of Plumbago indica hairy roots with yeast carbohydrate fraction, chitosan, manganese chloride, copper chloride and methyl jasmonate exhibited significant elevation (similar to 1.2 to 2 fold) of plumbagin production in shake flask culture as compared with control. Chitosan and methyl jasmonate elicitation also caused simultaneous plumbagin leaching into culture media. Three days' exposure of chitosan (200 mg l(-1)) and methyl jasmonate (80 mu M) together synergized total plumbagin yield to its maximum 11.96 +/- 0.76 mg g(-1) DW in shake flask culture. In bioreactor cultivation, a significant raise in fresh root biomass was recorded on day 20 as compared with control shake flask culture. Three days' exposure of chitosan (200 mg l(-1)) and methyl jasmonate (80 mu M) with 20 days old bioreactor-culture significantly improved total plumbagin production to 13.16 +/- 1.72 mg g(-1) DW with simultaneous plumbagin leaching into bioreactor media. (C) 2011, The Society for Biotechnology, japan. All rights reserved.