Evaluation of nutrient uptake and physical parameters on cell biomass growth and production of spilanthol in suspension cultures of Spilanthes acmella Murr.

Spilanthes acmella Murr. has a plethora of highly valuable biologically active compounds and has been listed as one of the important medicinal plants of the world. However, no perceptible biotechnological advances have been made for this genus to exploit or enhance its utility. To nullify the effect of seasonal variations, the present report is the first attempt to establish in vitro cell suspension cultures and to evaluate the production of spilanthol from them, a key component of the plant responsible for most of its pharmaceutical activities. The study examined the biomass growth in relation to the consumption of major nutrients and sucrose, agitation speed and dynamic change in pH. Results indicated that the consumption of phosphate resulted in the onset of decline phase in cultures. Spilanthol production was observed to be growth associated and maximum production occurred on the 15th day. Among the carbon sources, the highest production of spilanthol as 91.4 µg g(-1) DW was recorded in the medium supplemented with sucrose, followed by glucose which produced 56.8 µg g(-1) DW of spilanthol. Spilanthol could not be detected in fructose containing medium. Maximum viable cultures were obtained at a rotation speed of cells at 120 rpm. This study signifies the utility of Spilanthes suspension cultures for biosynthesis and constant production of spilanthol, throughout the year. The results of present study are useful for further scale-up process.