## 3 Results and Discussion
### Preparation and Chemical Characterization of SEWS
Although not a major source of amino acids, the SEWS might be used as a dietary supplement where enhanced amounts of the branched amino acids are needed. The SEWS contained a high amount of phenols (16.38%, Table 1). Chlorogenic acid (85.41% TIC) was in the highest relevant amount, followed by cinnamic (3.23% TIC) and p-hydroxybenzoic (2.76%) acids (Table 2). Syringic, ferulic, and caffe acids were also established (Table 2). [PERSON] et al. [54] also demonstrated that sunflower meal is a suitable source of phenols (with chlorogenic acid being in the highest amount). The highest yield of the latter was obtained by using acetone, but 60% ethanol was recommended for the extraction of chlorogenic acid if used in the food or pharmaceutical industries. A high amount of phenols (13.38%) was established in the ethanol-wash solute prepared from industrial rapeseed meal [16], although with a difference in the relative composition of the phenolic acids compared to those in the SEWS. [PERSON] et al. [55] obtained single phenolic compounds after enzymatic treatment of dry alcoholic extracts prepared from rapeseed and sunflower meals. While not desired as a part of the protein isolates [56], these phytochemicals are valuable for their antioxidant, antimicrobial, and anticarcinogenic properties [54; 57]. More specifically, chlorogenic acid was demonstrated to exert a beneficial \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{2}{c}{**Compound**} & \multicolumn{1}{c}{**RT**} & \multicolumn{1}{c}{**RI**} & \multicolumn{1}{c}{**TIC, \%**} \\ \hline \multicolumn{5}{c}{**B:** Nonpolar compounds} \\ \hline  & & Fatty acids & & \\
1 & Myristic acid & 12.60 & 1837 & 0.84 \\
2 & Palmitoleic acid & 15.34 & 1905 & 0.30 \\
3 & Palmitelaidic acid & 15.44 & 1912 & 0.73 \\
4 & Palmit acid & 15.79 & 1926 & 6.18 \\
5 & Linoleic acid & 18.63 & 2096 & 12.10 \\
6 & Oleic acid & 18.71 & 2099 & 0.14 \\
7 & Linolenic acid & 18.79 & 2102 & 1.72 \\
8 & Stearic acid & 19.07 & 2247 & 4.30 \\
9 & Arachidic acid & 20.65 & 2311 & 4.86 \\  & & Alkenes & & \\
10 & n-Eicosane & 17.01 & 2000 & 0.42 \\
11 & n-Tricosane & 20.31 & 2300 & 2.11 \\ \hline \multicolumn{5}{c}{**C:** Phenolic compounds} \\ \hline
1 & Salicylic acid & 8.60 & 1510 & 0.64 \\
2 & Cinnamic acid & 8.91 & 1557 & 3.23 \\
9 & P- & & & \\
3 & Hydroxybenzoic & 10.46 & 1642 & 2.76 \\  & acid & & & \\
4 & Vanillic acid & 11.18 & 1775 & 0.63 \\
5 & Syringic acid & 14.10 & 1884 & 1.85 \\
6 & Ferulic acid & 16.01 & 2103 & 0.90 \\
7 & Caffeic acid & 17.55 & 2140 & 0.81 \\
8 & Sinapic acid & 19.21 & 2253 & 0.74 \\
9 & Chlorogenic acid & 31.80 & 3111 & 85.41 \\ \hline \hline \end{tabular}
\end{table} 
Table 2: _Cont._effect on glucose and lipid metabolism [58] and promote wound healing by regulating the activity of metalloproteinases [59]. Compared to the ethanol-wash solute, obtained from rapeseed meal [12], the SEWS contained more than a 2.5-fold higher amount of total flavonoids (Table 1). The flavonoids are plant secondary metabolites with powerful antioxidant activity having the capacity to reduce the oxidation of biomolecules [1]. Therefore, flavonoid fractions or flavonoid-rich products, such as SEWS, could be potentially used as additives in the food industry for enhancement of food quality and shelf life or as a dietary supplementation contributing to the overall improvement of the health status of humans. The SEWS contained valuable microelements (Table 3). The contents of iron (259.02 mg/kg) and copper (109.36 mg/kg) were the highest, followed by zinc and manganese with 22.11 mg/kg and 5.10 mg/kg, respectively. Minerals in optimal concentrations are needed for humans and animals to maintain active physiological status. To provide adequate amounts of microelements, the diets in intensive livestock breeding are supplemented with synthetic premixes [60]. Microelement-rich plant-derived materials with natural origin might be a good alternative to currently used mixtures of inorganic salts.