Daily photon flux density (PFD) and culture temperature profile applied for (A) summer cultivation, with (reg. summer) and without thermal regulation (summer), (B) extreme summer cultivation with (reg. extreme summer) and without thermal regulation (extreme summer), and (C) winter cultivation with (reg winter) and without thermal regulation (winter). Only temperature values were altered between regulated vs non-regulated cultivations, PFDs remained the same.

Cultivation of the two strains in open raceway tanks. A represents the culture at T = 0, and B represents the culture at T = end. Both strains were cultivated in duplicates, n = 2.

Biomass concentration evolution for PM and NA for batch cultivation in open raceway tanks, under natural environment (NE). Data shown is the mean ± SD, n = 2.

Areal productivities (g/m2/d) determined during steady state continuous cultivation (D = 0.017/h) for PM and NA under the different thermal regimes. Values are mean ± SD, n = 6, Different letters indicate significant differences (p < 0.05) between the individual means for NA and PM, respectively.

(A) Yearly average light variation in Qatar and corresponding values used for PE calculation. B-Emergence of diverse PE (%) for two strains PM and NA over the main seasons in Qatar (with and without thermal regulation).

A.B.C. Variation in biochemical composition of the two strains under different thermal regimes Summer, Extreme Summer, Winter (with and without the thermal regulation) and when cultivated in natural environment (NE). Protein, lipid and carbohydrate values are means (n = 2) ± SD. Different superscripts indicate significant differences.

Variation in the fatty acid content in terms of SFA (saturated fatty acid), MUFA (monounsaturated fatty acid) and PUFA (polyunsaturated fatty acid) for PM and NA under the different thermal regimes representing summer and winter seasons with and without regulation. S, RS, W, RW and NE indicate the different conditions implemented on the strains and they stand for summer, regulated summer, winter, regulated winter and natural environment (open pond cultivation) respectively.

(A) Representative photographs of 96-hpf embryos exposed to PTU medium (negative control), Sparos zebrafeed (negative control), DEAB nanoparticles (positive control), and all concentrations of Microalgae feed. The red arrow shows the heart edema, the orange arrow shows the yolk edema, and the yellow arrow shows the short body length. (B) The survival rate of the microalgae feed at 96 hpf. (C) Graph demonstrating the LC50 of Microalgae compared to the DEAB (PC). n = 25.

A) Average body length, B) size of the yolk, C) size of the eye, and D) heart sac size following treatment, as captured using the HCImage software and analyzed with version 1.52a of the ImageJ software version. One-way analysis of variance (ANOVA) followed by the Dunnett test was used to compare the groups, **p < 0.01 and ***p < 0.001, n = 6.