Seaweed aquaculture is one of the fastest-growing maritime industries worldwide. Devaleraea mollis has emerged as a potential species for land-based cultivation in the Pacific Northwest of the United States given their high protein content. Land-based cultivation has the advantage of customization for high-quality biomass production. However, the high cost of commonly used nutrient medium, such as von Stosch enrichment medium (VSE) and Guillard’s f/2 medium (f/2), is one of the limitations of land-based cultivation of D. mollis. Therefore, development of cost-effective nutrient supplements without compromising biomass growth and quality is needed. This study aims to find cost-effective nutrient supplements for land-based cultivation of D. mollis.
The commercial fertilizer, Jack’s Special (JS), was evaluated as a potential alternative in the present study. Five experimental treatments, 1) ambient seawater (AS); 2) VSE; 3) f/2; 4) JS; 5) JS with vitamins (JSV), were used in the present study. The growth, tissue carbon and nitrogen, phycobiliprotein, and total protein contents of D. mollis were measured.
The growth of D. mollis cultivated did not differ significantly among the tested nutrient supplements (VSE, f/2, JS and JSV) except for AS. However, the tissue nitrogen and phycobiliprotein content of D. mollis cultivated in f/2, JS and JSV were significantly higher than those in VSE. Additionally, the highest total protein content of D. mollis was observed at JS and JSV. These results suggest that the commercial fertilizer, Jack’s Special, can replace the nutrient medium, f/2 and VSE, for land-based cultivation of D. mollis with reduced cost and enhanced protein quality.