Enhancing content and decreasing production costs of phycocyanin through phytohormone supplementation in Spirulina cultivations

Abstract

This study explores the potential of fractional supplementation of the phytohormone indole-3-acetic acid (IAA) to enhance phycocyanin production in Spirulina cultures. Microalgae cultures were supplemented with IAA at specific time points (days 0, 5, 10, 15, 20, and 25), reaching the same supplementation concentration (0.1 mg L⁻¹) in the final 30-day cultivation period. The continuous daily supplementation resulted in a remarkable 229 % (106.41 mg g⁻¹) increase in phycocyanin concentration and a 251 % (8.3 mg L⁻¹ d⁻¹) improvement in productivity compared to the control group without phytohormone addition (32.30 mg g⁻¹ and 2.4 mg L⁻¹ d⁻¹, respectively). Additionally, the strategy successfully reduced the production cost of the pigment by 71 %. This approach can potentially make microalgae-based products more accessible to the population while addressing the industry's need for cost-effective pigment production. The study offers a novel strategy for optimizing natural pigment production and microalgae cultivation.