The effect of medium compounds on growth and azadirachtin production in cell suspension culture of neem (Azadirachta indica)

Azadirachtin is an important secondary metabolite of neem which is used as a natural biopesticide. In this study the effect of different concentrations of sucrose (1, 2, 3, 4 and 5%), calcium chloride, monopotassium phosphate, potassium nitrate, magnesium sulfate and ammonium nitrate (0.5x, 1x, 1.5x, 2x and 2.5x concentrations of MS base medium) on neem cell suspension growth and azadirachtin production was investigated. Although there were no significant difference between some of the treatment in terms of studied indices, the highest amount of fresh and dry cells weight were obtained by using 3% sucrose, 1x calcium chloride, 1x magnesium sulfate and 1x ammonium nitrate (493.02 and 77.27 g/L), 2.5x monopotassium phosphate (500.97 and 80.77 g/L) and 0.5x potassium nitrate (495.01 and 78.41 g/L). The highest settled cell volume was obtained by application of 4% sucrose (59.69%), 1x calcium chloride and 1x ammonium nitrate (94.93%), 2.5x monopotassium phosphate (97.22%), 0.5x potassium nitrate (94.96%) and 2x magnesium sulfate (94.96%). Maximum amount of azadirachtin accumulation observed by using 4% sucrose (3.72 mg/g DW), 0.5x calcium chloride (3.80 mg/g DW), 0.5x monopotassium phosphate (3.73 mg/g DW), 1x and 1.5x potassium nitrate (3.69 mg/g DW), 1x magnesium sulfate (3.69 mg/g DW) and 1.5x ammonium nitrate (3.71 mg/g DW). The highest amount of azadirachtin production was 286.65 mg/L obtained in MS basal medium supplemented with 3% sucrose.