要約

Good growth of Tolypothrix scytonemoides (Gardner) Geitler was observed in low concentrations of NPK fertilizer, single superphosphate, and urea. Protein content decreased in cells grown in higher concentrations of tested tested chemical fertilizers. Phycobilin pigment contents were enhanced in cells grown in medium amended with NPK fertilizer but were lower in cells grown in 15 and 20 mg·L⁻¹ of single superphosphate and 10, 15, and 20 mg·L⁻¹ of urea. The rates of photosynthetic oxygen evolution and respiratory oxygen consumption were enhanced in cells grown in medium amended with all different concentrations of NPK fertilizer and low concentrations of single superphosphate. Nitrogenase activity was completely inhibited by 20 mg·L⁻¹ NPK fertilizer and 15 mg·L⁻¹ urea but it remained unaffected with the addition of single superphosphate. On one hand, glutamine synthetase activity decreased gradually in a dose-dependent manner in cells grown in NPK fertilizer and urea-amended medium, on the other hand, the cells grown in 10 mg·L⁻¹ single superphosphate exhibited the highest glutamine synthetase activity. Greatest exogenous carbohydrate release was observed in cells grown in 15 mg·L⁻¹ urea.