Abstract
A reliable protocol was optimized for callus initiation and cell suspension culture cell lines of Moringa oleifera for the enhanced production of bioactive metabolites, i.e., flavonoids. The impact of plant growth regulators concentrations (auxins and cytokinins) were assessed to develop the callus growth, biomass and flavonoid content of M. oleifera explants based cell suspension system. The leaf explant of M. oleifera was optimum for callus induction rather than other explants viz. hypocotyl, node and internode. The optimized liquid medium B2 [MS+BAP (2.0 mg/l) + NAA (0.5 mg/l)] without agar for callus induction with the highest induction rate (98.55 +/- 2.51%), the highest callus growth, i.e., biomass (17.55 g/explant) were selected for leaf explants. Incompact and fast growing calli, i.e., cell line were further transfered in the liquid medium 82, for agitate and maximum recovery of mass of cells of M. oleifera. The optimum time of subculture in B2, medium is at the 15 days followed by another 15 days time interval. Biomass and flavonoid (rutin, gallic acid, quercetin, apigenin and chlorogenic acid) was recorded high after 4 weeks (log phase) of liquid culture and slow down the growth, i.e., biomass and subsequently after 5 weeks (stationary phase) of culture in same medium (B2). The maximum contents of rutin (4.4 mu g/mg), quercetin (4.6 mu g/mg), gallic acid (3.02 mu g/mg), apigenin (4.8 mu g/mg) and chlorogenic acid (0.27 mu g/mg) DW basis respectively, was recorded at the 4th week of calli cultured on liquid 82 medium. This study provided an efficient platform for biosynthesis and production of valuable flavonoid contents in short span of time through cell suspension culture of M. oleifera.