Sara Saadatmand, Morteza Zamani
Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran
Key words: Nitrate, phosphate, mycosporine like amino acids, chlorophyll a, carotenoids.
The present study invested on the effect of different concentrations of NaNO3 (1.5, 2, 2.5 gl-1) and K2Hpo4 (0.04, 0.05, 0.06 gl-1) on chlorophyll a, carotenoids, fresh and dry weight measures, and the quality of mass absorption in Spirulina platensis alga. Findings revealed a significant increase in the amount of chlorophyll a and carotenoids in cultivation setting by increasing NaNO3 and K2HPO4, especially at 2.5gl-1NaNo3 and 0.06 gl-1 K2Hpo4 concentrations. More findings also revealed that nitrate or phosphate supplemented growth medium had reducing effects on fresh weight; but, adversely affected the dry weight. Here, there was an increase in concentration of NaNO3 and K2HPO4, especially for 2.5 gl-1nitrateand 0.05 gl-1phosphate concentration samples. It should also be mentioned that the highest dry mass measures were obtained in 2.5 gl-1 NaNO3, though mass absorption in Spirulina platensis was at the highest rate in 2 gl-1 nitrate and 0.06 gl-1 phosphate concentration samples. Supplementary findings also indicated that quantities of mycosporine like amino acids (MAAs) increased significantly by increasing nitrate and phosphate concentrations. Collectively, it could be concluded that the altered composition of cultivation medium, especially macro elements like nitrate and phosphate, may affect the composition of quasi-mycosporine like amino acids by changing nitrogen assimilation, photosynthetic pigments content, which leads to probably higher photosynthesis and stimulating shikimate pathway.
Get the original articles in Source: Volume 6, Number 5, March 2015 – IJB