## 3 Results and Discussion
### Amino Acid Composition  
The total amino acid compositions of the _Spirulina_ sp. protein extract and _Isochrysis_ sp. protein extract are shown in Table 1. The total amino acid contents of the whole _Spirulina_ sp. and _Spirulina_ sp. protein extracts were determined to be 314.71 g/kg DW and 380.99 g/kg DW, respectively, and the total amino acid contents of _Isochrysis_ sp. and the protein extracts were determined to be 257.06 g/kg DW and 22.20 g/kg DW, respectively, with the essential amino acid composition of approximately 40.93% of the total amino acid composition for _Spirulina_ sp. and 45.18% for the _Spirulina_ protein extract. The essential amino acid composition for the _Isochrysis_ sp. and _Isochrysis_ sp. protein extracts were 43.55% and 42.03% of the total amino acid composition, respectively, and were comparable to other reports [24]. The level of the essential amino acids lysine and methionine con tained in both the soluble protein extracts were 14.26 \(\mu\)g/mL and 9.08 \(\mu\)g/mL of lysine, respectively, for the _Spirulina_ sp. soluble protein extract and _Isochrysis_ sp. soluble protein extract and 0.913 \(\mu\)g/mL and 0.57 \(\mu\)g/mL of methionine, respectively. The _Spirulina_ sp. soluble protein extracts contained less methionine and lysine than previously reported by [PERSON] et al. [25], who reported methionine and lysine contents of 14 mg g\({}^{-1}\) (methionine) and 30 mg g\({}^{-1}\) (lysine). The free amino acid contents of both microalga protein extracts are shown in Table 2. \begin{table}
\begin{tabular}{c c c c c c} \hline  & & _Spirulina_ sp. & & & _Isochrysis_ sp. & \\ \hline \multirow{6}{*}{**Essential amino acids**} & \multicolumn{2}{c}{_Spirulina platensis_} & \multicolumn{2}{c}{_Spirulina platensis_} & \multicolumn{2}{c}{_Isochrysis_ T-_Iso_} & \multicolumn{2}{c}{_Isochrysis T-_Iso_} \\  & \multicolumn{2}{c}{**Whole Biomass**} & \multicolumn{2}{c}{**Protein Extract**} & \multicolumn{2}{c}{**Whole Biomass (g/g)**} & \multicolumn{2}{c}{**Protein Extract**} \\  & \multicolumn{2}{c}{**(g/kg)**} & \multicolumn{2}{c}{**(g/kg)**} & \multicolumn{2}{c}{**(kg)**} & \multicolumn{2}{c}{**(g/kg)**} \\ \hline
**Essential amino acids** & Isoleucine & 3.53 & 4.61 & 2.75 & 0.3 \\  & Leucine & 5.59 & 7.58 & 5.39 & 0.45 \\  & Valine & 4.54 & 5.46 & 3.64 & 0.4 \\  & Phenylamine & 2.95 & 4.38 & 3.07 & 0.3 \\  & Typtophan & 1.48 & 1.82 & 2.53 & 0.59 \\  & Lysine & 2.78 & 2.64 & 2.8 & 0.27 \\  & Threonine & 3.38 & 3.58 & 3.13 & 0.31 \\  & Methionine & 1.84 & 1.9 & 1.95 & 0.17 \\
**Non-essential amino acids** & Alanine & 5.38 & 5 & 4.88 & 0.54 \\  & Glycine & 3.28 & 4.11 & 3.46 & 0.36 \\  & Proline & 2.35 & 3.38 & 3.17 & - \\  & Tyrosine & 2.41 & 2.75 & 0.98 & 0.38 \\  & Asparatic acid and & 6.55 & 7.18 & 5.92 & 0.72 \\  & Glutamic acid and & 8.99 & 7.65 & 6.43 & 0.73 \\  & Arginine & 4.09 & 4.31 & 3.61 & 0.38 \\  & Serine & 3.06 & 3.63 & 2.72 & 0.27 \\  & Cysteine & 1.56 & 0.69 & 1.55 & 0.48 \\
**Total amino acids** & & 63.76 & 70.67 & 57.98 & 6.65 \\
**(TAA)** & & & & & \\
**Essential amino acids (EAA)** & & 26.09 & 31.97 & 25.26 & 2.79 \\
**Non-essential amino acids (NEAA)** & & 47.15 & 38.7 & 32.72 & 3.86 \\  & Protein & & & & \\
**Ash** & & & & & \(71.9\pm 8.6\%\) \\
**Lipid** & & & & & \(1.7\pm 1.1\%\) \\  & Lipid & & & & \(2.87\pm 1.2\%\) \\ \hline \end{tabular}
\end{table} 
Table 1: Proximate analysis and total amino acid content of the microalgal protein extracts.