Growth performance analysis of Spirulina platensis production by substituting K2SO4-K of kosaric medium with MOP-K

Abstract

Five media were formulated with 0% (control, T₁), 25% (T₂), 50% (T₃), 75% (T₄) and 100% (T₅) inclusion of low-cost muriate of potash (MOP)-potassium (K) replacing high-cost reagent K₂SO₄-K and Spirulina platensis was cultured for 18 days. Cell dry weight, optical cell density and chlorophyll-a content of S. platensis cultured in five treatments were registered at every three-day interval and economic performance was calculated to observe the effect of K₂SO₄-K replacement with MOP-K. The cell biomass production and chlorophyll-a content of S. platensis cultured in 25 and 50% use of MOP-K instead of K₂SO₄-K (T₂ and T₃) did not represent any significant difference with the control treatment of 100% K₂SO₄-K (T₁). However, further addition of MOP-K in T₄ and T₅ significantly reduced the cell growth and pigment content of S. platensis. In addition, a significant reduction of production cost was calculated as more percentage of K₂SO₄- K was replaced with MOP-K.