# Evaluation of _Sambucus nigra_ L. Biopotential as an Unused Natural Resource
## 3 Results and Discussion
### Biological Activity
#### 3.2.2 Enzyme Inhibitor Activity of Fresh Fruits of Elderberry Extracts
In order to find novel natural tyrosinase inhibitors, the analysis of fresh elderberry extracts has resulted in excellent inhibitory activity and is summarized in Table 4. Achieving the best inhibitory ability was 50% EtOH MAE, 243.70 mg KAE/g E, while the inhibitory capacity of 50% EtOH of the UAE extract was 240.41 mg KAE/g E. MAC extract accomplished the lowest tyrosinase inhibition value: 102.11 mg KAE/g E. H\({}_{2}\)O extracts realized good results in terms of anti-tyrosine activity, but the obtained values were lower in relation to 50% EtOH extracts and ranged from 80.54 to 96.63 mg KAE/g E. The presence of secondary metabolites in elderberry extracts, especially rutin, chlorogenic acids, and torsolic acid, which correlate well with tyrosinase inhibition, enabled the analyzed extracts to achieve very good inhibition of tyrosinase (Table S1, Supplementary Material). The results achieved by fresh elderberry extracts in the process of inhibition of excessive tyrosinase enzyme activity, especially EtOH MAE extract could be considered as a starting point and a potential guideline for the formulation of potentially new products based on the protective role of the skin. Preventing the development of diabetes as the leading chronic disease of modern society is based on the inhibition of excessive activity of the enzymes \(\alpha\)-amylase and \(\alpha\)-glucosidase. In this regard, fresh elderberry extracts were examined as potential natural inhibitors of these enzymes. Investigated elderberry extracts exerted strong inhibitory power against \(\alpha\)-amylase than \(\alpha\)-glucosidase, where all the extraction techniques leaded to an approximately similar result. In the ability to inhibit \(\alpha\)-amylase and \(\alpha\)-glucosidase, \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \begin{tabular}{c} **Extraction** \\ **Technique** \\ \end{tabular} & **Solvent** & \begin{tabular}{c} **AChE Inhibition** \\ **(mg GALAE/g E) * \\ \end{tabular} & \begin{tabular}{c} **BChE Inhibition** \\ **(mg GALAE/g E) * \\ \end{tabular} & \begin{tabular}{c} **Tyrosinase** \\ **Inhibition** \\ **(mg KAE/g E) ** \\ \end{tabular} & \begin{tabular}{c} **\(\alpha\)-** \\ **Inhibition** \\ **(mmol ACE/g E) *** \\ \end{tabular} & \
\begin{tabular}{c} **\(\alpha\)-** \\ **Inhibition** \\ **(mmol ACE/g E) *** \\ \end{tabular} \\ \hline
\begin{tabular}{c} MAE \\ 50\% \\ \end{tabular} & 50\% & 5.05 \(\pm\) 0.001 1 & 4.00 \(\pm\) 0.05 2 & 240.41 \(\pm\) 0.01 3 & 0.31 \(\pm\) 0.01 4 & 0.083 \(\pm\) 0.05 4 \\ MAC & 5.09 \(\pm\) 0.005 2 & 1.29 \(\pm\) 0.01 5 & 102.11 \(\pm\) 0.01 5 & 0.08 \(\pm\) 0.01 5 & 0.086 \(\pm\) 0.005 5 \\ MAE & 4.50 \(\pm\) 0.01 6 & 0.51 \(\pm\) 0.01 5 & 96.63 \(\pm\) 0.01 4 & 0.07 \(\pm\) 0.00 5 & 0.080 \(\pm\) 0.06 4 \\ UAE & H\({}_{2}\)O & 4.78 \(\pm\) 0.005 2 & 1.26 \(\pm\) 0.01 5 & 82.95 \(\pm\) 0.001 6 & 0.06 \(\pm\) 0.00 5 & 0.06 \(\pm\) 0.00 4 \\ MAC & 5.00 \(\pm\) 0.05 2 & 1.09 \(\pm\) 0.01 4 & 80.54 \(\pm\) 0.001 6 & 0.06 \(\pm\) 0.00 5 & 0.043 \(\pm\) 0.00 4 \\ \hline \hline \end{tabular}  
* mg galantamine equivalent per g of extract, ** mg koic acid equivalent per g of extract, *** mmol acarbose equivalent per g of extract \(\pm\) 3 SD. Means followed by different letters (2-6) differ significantly at \(p<0.05\).  
\end{table} 
Table 4: Enzyme inhibitor capability of fresh fruits of elderberry extracts. there was no statistically significant difference between the 50% EtOH extracts of all three extraction techniques. In terms of correlation, the best correlation was observed between the content of rutin and \(\alpha\)-glucosidase inhibition, so rutin probably had the strongest effect on this enzyme inhibition (Table S1, Supplementary Material). To achieve the general conclusion on antioxidant and enzyme inhibitor activities and possible classification of the samples, PCA was carried out using the datasets containing variables related to antioxidant and enzyme inhibitor activities (Figure 3).