Effect of Different Purities of Seed Cells and Culture Media on the Growth Pattern and Protein Content of Spirulina Platensis

Spriulian platensis is a type of microalgae commonly used as natural fish feed. The purity of cell seedlings represents an internal factor, while the culture media acts as an external factor that can limit microalgae growth. This research investigates how varying purities of cell seedlings and culture media affect the growth patterns and protein content of Spriulian platensis, as well as to identify the optimal purity of cell seedlings and culture media that best promote growth patterns and protein content. The research method employed was an experimental design using a completely randomized factorial design with four treatment combinations and three replicates. The results showed that factor A (purity of seed cells) significantly affected growth patterns, including the lag phase duration, specific growth rate, and maximum density, but did not influence the final density Spriulian platensis. Factor B (culture media) had no significant effect on any of the variables. The combination of axenic seedlings with Pro Analis media was identified as the best treatment, producing a lag phase duration of (-4.17 ± 0.03 cells/day), a growth rate of (0.33 ± 0.01 cells/day), a maximum density of (6.43 ± 0.02 log cells/ml), and a final density of (5.78 ± 0.03 log cells/ml). The protein content across all treatments remained consistent at 58-60%. The study concludes that the purity of cell seedlings is a critical factor in determining the growth pattern of Spirulina platensis, particularly affecting the lag phase, growth rate, and maximum density.