Improving Protein Recovery from Limnospira platensis through Enzymatic-Surfactant Synergy

By 2050, the global population is expected to reach 9.5 billion, driving a projected 32–78% increase in protein demand and reinforcing the urgency for sustainable, high-quality protein sources in line with the UN Sustainable Development Goals. Since conventional animal-derived proteins impose significant environmental pressures, microalgae represent a sustainable alternative due to their rapid biomass accumulation, low resource inputs and abundance of proteins, polyunsaturated fatty acids and bioactive metabolites. Limnospira platensis (Spirulina) is particularly notable for its elevated protein content, positioning it as a competitive substitute for traditional protein sources such as soy, eggs and meat. However, its structurally resilient cell wall and polysaccharide matrix have necessitated the use of energy-intensive, solvent-based extraction approaches. In this context, lysozyme has emerged as a promising biocatalyst to support greener protein recovery. This study investigated whether lysozyme incubation in the presence of Triton X-100 enhances protein release by mitigating micelle formation. Lyophilized biomass was treated with increasing amount of lysozyme (from 1250 to 5000 U/g of biomass) for 1–2 h, with Triton X-100 maintained at 0.5% (w/v). The optimal condition (2500 U/g) yielded about 30% of protein after 1 h and 35% after 2 h with an approximate 24% increase, demonstrating that the synergistic action of lysozyme and surfactant markedly improves cell wall disruption, thus significantly enhancing protein recovery.