Microalgae are the most important plankton for nutrition of marine larval organisms. The objective of this study is to apply the Plackett-Burman statistical design to specify which nutrient factor(s) optimizes the nutritional contents (protein, carbohydrates, lipids, and omega3 fatty acids) in the marine microalga Tetraselmis chuii. Tetraselmis chuii was cultured on F/2 medium (as control) reaching the maximum growth in the 10th day. By application of the design, contents of protein and carbohydrates increased at high concentrations of NO3 and PO4 by 43.5% and 50%, respectively. Total lipid increased by 91.5% at low concentrations of NO3 and PO4. Also, omega3 fatty acids, including Alpa-linolenic acid, Eicosatetraenoic, Eicosapentaenoic, and Decosahexaenoic, increased about 3 times. The enrichment of Artemia franciscana with T. chuii cultured on the optimized media showed increases in the total protein, carbohydrates and lipids by 58.9, 106.6 and 173%, respectively. The omega3 fatty acids in A. franciscana enriched with the optimized T. chuii medium constitute 61.1% of the total fatty acids versus 34.8% for that in the F/2 control medium. These acids including C18:3, C20: 5, and C22: 6 are similar to those found in T. chuii. Therefore, algal species rich in omega3 fatty acids may cover the requirements for the high survival, growth and quality of fish larvae.
Key words: Marine microalga-Protein, Carbohydrates, Omega3 fatty acids, Artemia franciscana
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