A modified method for a fast and economic determination of nitrate concentrations in microalgal cultures

The sodium salicylate method for nitrate determination in liquids was adapted for the use in microtiter plates and the applicability of this quick, easy and economic test was examined for cyanobacterial mineral media. The assay was found to be suitable for a direct detection of nitrate ions up to a concentration of 450 mg L-1 within the commonly used mineral media BG-11, BBM, ASN-III and Zarrouk. The salicylate method was successfully used for the correlation of Synechococcus elongatus PCC 6301 cell growth and nitrate consumption over 17 cultivation days.

Automated summary

The sodium salicylate method was adapted for nitrate determination in microtiter plates and its applicability in cyanobacterial mineral media was examined. The assay was suitable for direct detection of nitrate ions up to a concentration of 450 mg L-1 in commonly used media. Additionally, the salicylate method successfully correlated cell growth and nitrate consumption over a 17-day cultivation period in Synechococcus elongatus PCC 6301.