## 3 Results and Discussion
### Polyphenolic Profile by HPLC-DAD  
The prepared tinctures were subjected to the qualitative evaluation of the polyphenol profile by the HPLC-DAD method. The compounds identified in individual samples are presented in Table 4 and sample chromatograms recorded at 280 nm (for samples 1 and 4) are shown in Figure 2. All samples are dominated by metabolites typical for green walnuts, belonging to the groups of phenolic acids (gallic acid, syringe acid, and their derivatives), tannins (catechin isomers, and condensed catechins), and flavonoids (rutin and quercetin). The presence of naphthoquinones was also found, but the juglone, a typical metabolite of _J. regia_, was not detected. Such compounds were previously reported in tinctures prepared from unripe walnuts. Regardless of the variety and solvent system used, gallic and syringe acid [33], and (+)-catechin, as well as (\(-\))-epicatechin [5] were found to be the dominant compounds. Using the combined LC/MS technique, depsides were also detected--derivatives of caffeic, coumaric, and quinic acids [32]. According to the literature, juglone occurred in tinctures and liquens however, its content may be influenced by various factors. It has been shown that juglone content is significantly lower in tinctures than in green husk extracts, and what's even more important, its content in husks changes seasonally [15; 33]. Juglone is also a relatively unstable compound, it can decompose e.g., under the influence of light [34]. The exact identification of the naphthoquinones present in the tinctures was not possible without the available standards. \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Peak** & **Retention** & **Absorption Maxima** & & & & **Sample** & & \\
**No.** & **Time [min]** & **Absorption** & **Information** & **1** & **2** & **3** & **4** & **5** & **6** \\ \hline
1 & 2.12 & 272 & Gallic acid & + & + & + & + & + \\ \hline
2 & 3.50 & 265, 426 & Naphthoquinone & + & \(-\) & \(-\) & \(-\) & \(-\) & \(-\) \\ \hline
3 & 3.64 & 311, 295 sh & Coumaric acid derivative & + & + & + & + & + \\ \hline
4 & 4.68 & 275 & (+)-catechin & + & - & tr & + & + \\ \hline
5 & 5.00 & 219, 266, 422 & Naphthoquinone & + & + & \(-\) & \(+\) & \(+\) \\ \hline
6 & 5.13 & 263, 317 sh & Dihydroxybenzoic acid isomer & \(-\) & \(-\) & \(-\) & \(+\) & \(-\) & \(-\) \\ \hline
7 & 5.68 & 273 & (\(-\))-epicatechin & + & tr & tr & + & + & tr \\ \hline
8 & 5.85 & 276 & Syringic acid & + & + & tr & + & + \\ \hline
9 & 6.42 & 260, 326 sh & Dihydroxybenzoic acid isomer & + & + & + & + & + \\ \hline
10 & 6.81 & 223, 345 sh, 359 & unknown & + & + & + & \(-\) & + & + \\ \hline
11 & 7.31 & 234 sh, 259 sh, 363 & Rutin & tr & tr & tr & tr & + & tr \\ \hline
12 & 7.50 & 266 & Gallic acid derivative & + & + & + & + & + \\ \hline
13 & 7.89 & 272, 301 sh, 318 sh, 383 & Naphthoquinone & \(-\) & + & + & \(-\) & \(-\) & \(+\) \\ \hline
14 & 7.96 & 269, 378 & Naphthoquinone & + & + & + & + & + \\ \hline
15 & 8.41 & 258, 348 & Quercitrin & tr & tr & tr & + & tr \\ \hline
16 & 13.43 & 230 sh, 283 & Eugenol & \(-\) & \(-\) & \(+\) & \(-\) & \(-\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Polyphenolic profiles of tested green wanut tinctures. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline  & **TPC** & **TFC** & **FRAP** & **DPPH** & **ABTS** \\ \hline TPC & 1.000 & & & & \\ TPC & 0.618 & 1.000 & & & \\ FRAP & 0.910 & 0.855 & 1.000 & & \\ DPPH & 0.876 & 0.676 & 0.893 & 1.000 & \\ ABTS & 0.752 & 0.942 & 0.931 & 0.773 & 1.000 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Correlation matrix for total phenolic and flavonoid content, and antioxidant capacity. The most significant effect of the addition of spices to tinctures is the introduction of eugenol in the case of the addition of cloves (tincture 4). In the case of this sample, it is the dominant peak in the chromatogram (Figure 2), which proves its high content as the result of enrichment.