Application of Plackett–Burman design for the high production of some valuable metabolites in marine alga Nannochloropsis oculata

Microalgae have efficient nutritional influence to obtain high survival growth and quality of fish larvae and to promote the growth of brine shrimp. In this work the Plackett–Burman statistical design was applied to specify which nutrient factor(s) optimize the nutritional contents [protein, carbohydrate, β-carotene, ascorbic acid and free radical scavenging activity (DPPH)] in the marine alga Nannochloropsis oculata used in aquaculture to maximize marine hatchery production. N. oculata was cultured on F/2 medium (as control) to reach its maximum growth. The obtained results showed that the maximum growth, chlorophyll-a,b and carotenoid contents were attained after 10 days. The contents of all studied parameters in N. oculata grown on the optimized medium after10 days increased significantly (P ⩽ 0.1) than those on control with low concentration of PO4 (2.5 g l−1) and with high concentration of NO3 (112.5 g l−1) except for cell numbers and DPPH. Significant increases in the protein, carbohydrate, ascorbic acid, β-carotene and DPPH in Artemia franciscana enriched with N. oculata cultured on the newly optimized medium were observed.