## 3 Results and Discussion
### Characterization of Aronia Extract
#### 3.1.1. Phenolic Content in the Aronia Extract  
The results show that the aronia extract was rich in biologically active compounds. Therefore, the total polyphenol content was 5522 mg GAE/100 g DW extract; the total flavonoid and tannin content were, respectively, 5071 mg GAE/100 g DW and 549.2 mg TAE/100 g DW extract. [PERSON] et al., studied four aronia specimens and showed that the species and districts of fruit growth influenced the total content of polyphenols and flavonoids. In the case of A. melanocarpa extract, they were, respectively, 40.06 mg GAE/g and 13.16 mg QE/g [33]. [PERSON] et al., studied the influence of extraction temperature on the total polyphenol content in hydroalcoholic extracts from aronia waste and found that at 73.3 \({}^{\circ}\)C the extraction rate of polyphenols increased 4.5 times (7700 mg GAE/L) compared to 40 \({}^{\circ}\)C (1711 mg GAE/L) [34]. [PERSON] et al., studied 23 samples of aronia fruits (Nero variety) in which the total polyphenol content ranged from 1022.4 to 1795.5 mg GAE/100 g FW [35]. Bibliographic sources attest that the variety, cultivation and harvesting conditions can significantly influence the total polyphenol content, the values of which can reach up to 8000 mg/100 g DW [36]. [PERSON] et al., demonstrated that the ripening state of the aronia fruits influenced the flavonoid content, showing that during the ripening period it decreased from 7-11 g/100 g DW to 4 g/100 g DW [37]. According to the study by [PERSON] et al., in dried fruits and powders of aronia the flavonoid content varied between 867 mg GAE/100 g DW and 3317 mg GAE/100 g DW [38]. In the study by [PERSON] et al., it was shown that in the aronia fruits harvested in 2006-2007, the tannin content varied between 1.174 g/100 g and 1.072 g/100 g fruit [39]. Table 3 shows the polyphenols identified by the HPLC method in hydroethanolic extract from aronia fruits. The main phenolic compounds detected in aronia extract were catechin (828.49 \(\mu\)g/100 g DW), ferulic acid (296.24 \(\mu\)g/100 g DW), epicatechin (252.69 \(\mu\)g/100 g DW), salicylic acid (142.47 \(\mu\)g/100 g DW), protocatechin (101.08 \(\mu\)g/100 g DW), ferulic acid methyl ester (79.57 \(\mu\)g/100 g DW), polydatin (68.28 \(\mu\)g/100 g DW), but also gallic, para- and meta-benzoic acids, procyanidin B1 and B2, etc. [PERSON] et al., identified and quantified polyphenic compounds, especially gallic, caffeic, p-coumaric, ellagic, chlorogenic and flavonoids acids (quercetin and kemferol) in two varieties of fresh aronia fruits (Nero and Viking variety) [5]. [PERSON] et al., used high-performance liquid chromatotagra \begin{table}
\begin{tabular}{l c} \hline \hline
**Indices** & **Quantity** \\ \hline \multicolumn{3}{c}{_Anthocyanins_} \\ \hline Total anthocyanin content (mg cyanidin-3-glucose & 412.0 \(\pm\) 1.1 \\ equivalents (CGE)/100 g DW) & 263.7 \(\pm\) 1.8 \\ Cyanid-3-arabinozide (mg/100 g DW) & 125.7 \(\pm\) 1.4 \\ Cyanid-3-glucose (mg/100 g DW) & 11.5 \(\pm\) 0.5 \\ Petunid-3-glucose (mg/100 g DW) & 11.1 \(\pm\) 0.9 \\ \hline \multicolumn{3}{c}{_Organic acids_} \\ \hline Malic acid (mg/100 g DW) & 4836 \(\pm\) 15 \\ Citric acid (mg/100 g DW) & 362 \(\pm\) 9 \\ Ascorbic acid (mg/100 g DW) & 66 \(\pm\) 3 \\ Acetic acid (mg/100 g DW) & 312 \(\pm\) 10 \\ \hline \multicolumn{3}{c}{_Antioxidant activity_} \\ \hline Antioxidant activity (DPPH) (mmol redox equivalents & 191.66 \(\pm\) 5.32 \\ (TE)/100 g DW) & \\ \hline \multicolumn{3}{c}{_CIELab Chromatic Parameters_} \\ \hline L\({}^{*}\) & 30.21 \(\pm\) 0.17 \\ a\({}^{*}\) & 34.72 \(\pm\) 0.05 \\ b\({}^{*}\) & 9.46 \(\pm\) 0.08 \\ C\({}^{*}\) & 36.00 \(\pm\) 0.06 \\ H\({}^{*,\circ}\) & 15.2 \(\pm\) 0.3 \\ \hline DPPH = 2,2-diphenyl-1-picrylhydraz-ly hydrate, L\({}^{*}\)—luminosity; a\({}^{*}\)—red/green component; b\({}^{*}\)—yellow/blue component; C\({}^{*}\)—chromatically; H\({}^{*}\)—hue angle. \\ \hline \hline \end{tabular}
\end{table}