# Nutritional Profiling of Underutilised _Citrullus lantus mucosospermus_ Seed Flour
## 3 Results and Discussion
### Effect of Supercritical CO\({}_{2}\) Extraction on the Proximate Composition of Egusi Flour
\begin{table}
\begin{tabular}{l l l l l} \hline \hline  & \multicolumn{4}{c}{**Defatted Egusi flour \({}^{1,2}\)**} \\ \cline{2-5}
**Proximate (\%)** & **Raw Egusi** & **DEF1** & **DEF2** & **DEF3** \\ \hline Moisture & 8.1 \(\pm\) 0.0 \({}^{\text{a}}\) & 10.1 \(\pm\) 0.0 \({}^{\text{a}}\) & 6.6 \(\pm\) 0.5 \({}^{\text{b}}\) & 5.3 \(\pm\) 0.0 \({}^{\text{c}}\) \\ Crude protein & 28.4 \(\pm\) 0.0 \({}^{\text{a}}\) & 60.4 \(\pm\) 0.1 \({}^{\text{a}}\) & 48.4 \(\pm\) 0.4 \({}^{\text{b}}\) & 60.1 \(\pm\) 0.6 \({}^{\text{a}}\) \\ Crude fat & 52.0 \(\pm\) 0.0 \({}^{\text{a}}\) & 0.6 \(\pm\) 0.0 \({}^{\text{b}}\) & 0.4 \(\pm\) 0.0 \({}^{\text{b}}\) & 0.7 \(\pm\) 0.0 \({}^{\text{b}}\) \\ Carbohydrate & 5.2 \(\pm\) 0.0 \({}^{\text{a}}\) & 19.5 \(\pm\) 13 \({}^{\text{b}}\) & 34.9 \(\pm\) 1.7 \({}^{\text{c}}\) & 23.4 \(\pm\) 2.3 \({}^{\text{c}}\) \\ Fibre & 2.7 \(\pm\) 0.1 \({}^{\text{a}}\) & 4.4 \(\pm\) 0.3 \({}^{\text{a}}\) & 3.4 \(\pm\) 0.3 \({}^{\text{b}}\) & 4.4 \(\pm\) 0.4 \({}^{\text{a}}\) \\ Ash & 3.6 \(\pm\) 0.0 \({}^{\text{a}}\) & 5.0 \(\pm\) 1.3 \({}^{\text{a}}\) & 6.3 \(\pm\) 1.9 \({}^{\text{a}}\) & 6.1 \(\pm\) 2.5 \({}^{\text{a}}\) \\ \hline \hline \end{tabular} \({}^{\text{I}}\) Values are mean \(\pm\) standard deviation of 5 replicates. Means with a different superscript in each row differ significantly (\(p\leq 0.05\)). \({}^{\text{2}}\) DEF1 = flour extracted at 60 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 450 bar; DEF2 = flour extracted at 55 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 600 bar; DEF3 = flour extracted at 75 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 600 bar.  
\end{table} 
Table 1: Proximate composition of raw and defatted egusi flour. Figure 1: Defatted egusi flour DEF1 = flour extracted at 60 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 450 bar; DEF2 = flour extracted at 55 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 600 bar; DEF3 = flour extracted at 75 \({}^{\circ}\)C, carbon dioxide flow rate 30 g/h, and pressure 600 bar). and reducing the risk of colon cancer [34]. The high fibre content of defatted egusi flour makes it a functional ingredient in therapeutic food formulation. Effect of Supercritical CO\({}_{2}\) Defatting on the Amino Acid Composition of Defatted Egusi Flour  
The amino acid composition indicated in Table 2 shows the presence of 14 amino acids, with glutamine being the highest. Glutamine is found chiefly in muscles, consisting of 19% nitrogen, making it the primary carrier of nitrogen in muscle cells. Another glutamine attribute is its flavour-enhancing role in food [35]. In defatted egusi flour, glutamine was as high as 12.9 g/100 g. The concentration of sulphur-containing amino acids (methionine) decreased with increased pressure and temperature to 600 bar and 75 \({}^{\circ}\)C. The decrease in sulphur-containing amino acids reflects the instability of amino acids when subjected to heat treatment and high-pressure [36]. Methionine considerably contributes to body cells' functionality by influencing cellular redox state and helping with detoxification [24]. According to [PERSON], 2011, in sunflower seeds, the amino acid content is high enough, with lysine and methionine ranging from 0.6 to 0.7 g/100 g and 0.3 to 0.5 g/100 g, respectively [37]. Lysine is not produced in animals or humans, making it an essential amino acid that must be ingested in food with high lysine protein [38]. The recent FAO pattern for the amino acid advised consuming 15-22 mg/kg/day of methionine and 30 mg/kg/day of lysine [28]. Defatted egusi flour was a source of lysine, ranging between 2.4 g/100 g for DEF1 and 2.6 g/100 g for DEF2, with no significant differences. The high glutamic and aspartic acid contents in defatted egusi flour were similar to those in seaweeds (26). These compositions are high in egusi flour, as the essential amino acid present is similar to the recommended value.