## 3 Results
### Interactive Effect between Growth Condition and Species on Nutritional Composition  
3.3.1. Protein and Nutritive Minerals  
The % protein content of the three Amaranth species is shown in Table 5. The highest protein content was recorded in OMET grown _A. cruentus_ (28.6%), followed by OMET grown _A. caudatus_ and non-OMET grown _A. cruentus_ (24.1%). The lowest protein content was recorded in non-OMET grown _A. tricolor_ (20.3%), not significantly different from the % protein recorded in non-OMET grown _A. caudatus_ (21.4%). Table 6A represents the contents of macro-elements (Ca, Mg, K, and P) and Table 6B shows micro-elements (Cu, Mn, Fe, Se, and Zn) in three Amaranth species grown under the OMET and non-OMET growing system. The OMET grown _A. cruentus_ had the highest Ca (130 mg/kg) and P (34.7 mg/kg) contents, while the highest Mg (82.5 mg/kg) and K (276 mg/kg) contents were found in the OMET grown _A. tricolor_. Non-OMET grown _A. cruentus_ recorded the lowest concentrations of Ca (88.3 mg/kg), Mg (56.6 mg/kg), and K (217 mg/kg) in comparison to all other studied Amaranth species grown under both OMET and non-OMET. The same trend was observed in OMET grown _A. tricolor_ that had \begin{table}
\begin{tabular}{l l l l l l} \hline \hline
**Retention** & \multirow{2}{*}{\begin{tabular}{l} **Exact Mass** \\ **(g/mol)** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{l} **Mass Generated ESI** \\ **(-) TOF MS (g/mol)** \\ \end{tabular} } & \multirow{2}{*}{**Fragmentation**} & \multirow{2}{*}{
\begin{tabular}{l} **Chemical** \\ **Formula** \\ \end{tabular} } & \multirow{2}{*}{**Tentative Structural Assignment**} \\
15.658 & 474.4557 & 474.08423 & 474.08758:246 475 & \multirow{2}{*}{
\begin{tabular}{l} C\({}_{21}\)H\({}_{30}\)O\({}_{12}\) \\ 3-methylbutylglycoside \\ \end{tabular} } \\
8093 & 219.23 & 218.10211 & 218.10655:4843 219 & \multirow{2}{*}{\
\begin{tabular}{l} C\({}_{9}\)H\({}_{17}\)NO\({}_{5}\) \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{l} Pantothenic acid \\ \end{tabular} } \\
21.15 & 468.46 & 467.15897 & 467.13629:1292 468 & \multirow{2}{*}{\
\begin{tabular}{l} C\({}_{22}\)H\({}_{28}\)O\({}_{11}\) \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{l} 6-O-(4-Hydroxybenzoylyl)-ajugol \\ \end{tabular} } \\
17.63 & 420.41 & 420.3132 & 268.03810:269.04341 & \multirow{2}{*}{\
\begin{tabular}{l} C\({}_{21}\)H\({}_{24}\)O\({}_{9}\) \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{l} Apigenin 7-O-glucose \\ \end{tabular} } \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Tentative identification of HPLC-Q-TOF-MS untargeted metabolites of Amaranth species. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Amaranth Species \& Treatment** & **Protein (\%)** \\ \hline _A. caudatus_ & OMET & 24.1 \(\pm\) 0.039 b \\ \cline{2-3}  & non-OMET & 21.4 \(\pm\) 0.044 d \\ \hline _A. cruentus_ & OMET & 28.6 \(\pm\) 0.46 a \\ \cline{2-3}  & non-OMET & 24.1 \(\pm\) 0.040 b \\ \hline _A. tricolor_ & OMET & 22.7 \(\pm\) 0.036 c \\ \cline{2-3}  & non-OMET & 20.3 \(\pm\) 0.042 d \\ \hline _p_-value & \multicolumn{2}{c}{0.04} \\ \hline \hline \end{tabular} Different letters show significance difference at _p_\(\leq\) 0.05.  
\end{table} 
Table 5: The effect of OMET system on total protein % found in three Amaranth species. the highest concentration of P. In contrast, the non-OMET grown _A. tricolor_ had the lowest concentration of P (21.4 mg/kg) when compared to the other species under both treatments. There was no significant difference Ca (104 mg/kg DW) measured in _A. caudatus_ in both treatment and OMET grown _A. tricolor_. Figure 5: HPLC-MS-QT of untargeted metabolites profiling of _Amaranthus caudatus_, _Amaranthus cruentus_, and _Amaranthus tricolor_, (**A**) unsupervised PCA and (**B**) supervised PCA (1 = OMET ad 2 = non-OMET). Red triangles = OMET grown _A. caudatus_. yellow triangles = non-OMET grown _A. caudatus_. Red pentagon = OMET grown _A. cruentus_. Dark Blue triangles = non-OMET grown _A. cruentus_. Light Blue rhombus = OMET grown _A. tricolor_. Purple pentagon = non-OMET grown _A.