Elicitation of pharmaceutical alkaloids biosynthesis by salicylic acid in marine microalgae Arthrospira platensis

Background and objective: Arthrospira platensis, an edible microalga approved by the World Health Organization, is known to be a rich natural source of valuable secondary metabolites with medicinal properties. The aim of this research was to determine the effect of salicylic acid (an abiotic elicitor) on biomass production, as well as the amount of alkaloids accumulated in Arthrospira platensis. Materials and methods: Salicylic acid was added to the medium culture at different concentrations on the third, seventh, tenth, fourteenth, and seventeenth days and its effects were determined after 24 h. The presence of alkaloid in the methanol extracts was confirmed by thin layer chromatography and quantified by bromocresol green. Results: The biomass and alkaloid production was increased with 5 and 20 mu M salicylic acid treatment, whereas salicylic acid at 100 mu M had a negative effect on the growth and biomass accumulation. The concentrations of alkaloids in control cultures ranged from 31.0 +/- 1.0 to 44.1 +/- 0.7 mu g Atropine/mg extract. The highest value of total alkaloids was obtained in cells treated with salicylic acid at a concentration of 5 mu M, followed by 20 mu M by the 15th day of culture; the levels were 1.7 and 1.4 times of the control, respectively. Conclusion: From the study, it is clear that the positive effect of salicylic acid on the growth and alkaloid production would make this elicitor an interesting candidate for increasing productivity in large scale process enterprises.