Medium composition potentially regulates the anthocyanin production from suspension culture of Daucus carota

In the present study, an effort has been made to optimize various culture conditions for enhanced production of anthocyanin. Nutrient content of MS medium (ammonium to potassium nitrate ratio and phosphate concentration) had a profound influence on the cell biomass and anthocyanin accumulation in cell suspension cultures of Daucus carota. Suspension cultures were carried out in shake flasks for 18 days and examined for cell growth, anthocyanin synthesis, anthocyanin yield and development of pigmented cells in relation to the uptake of total sugar, extracellular phosphate, nitrate and ammonia. The addition of NH4NO3 to KNO3 ratio (20.0 mM: 37.6 mM) in the suspension culture media resulted in a 2.85-fold increase in anthocyanin content at day 3. Similarly, a lower concentration of KH2PO4 (0.45 mM) in the MS medium resulted in 1.63-fold increase in anthocyanin content at day 9. The total sugar uptake was closely associated with a significant increase in anthocyanin accumulation. Total sugar and nitrate were consumed until 9-12 days, while ammonia and phosphate were completely consumed within 3 days after inoculation. After 9 days, cell lysis was observed and resulted in the leakage of intracellular substances. These observations suggest that anthocyanin was synthesized only by viable pigmented cells and degraded rapidly after cell death and lysis. This study signifies the utility of D. carota suspension culture for further up-scaling studies of anthocyanin.