## 3 Results and Discussion
### Enzyme Inhibitory Activities  
In the present work, the inhibitory activities of extracts against cholinesterase (AChE and BChE), amylase, glucosidase and tyrosinase have been investigated. The results are summarized in Table 5. The theory of enzyme inhibition is a potent tool in drug development, enabling the precise regulation of enzyme activity to alleviate the pathological symptoms associated with widespread health issues. By comprehending the intricate interactions among various enzymes and their impacts on biological pathways, scientists can devise medications that specifically target certain areas and impede particular processes. This approach has already demonstrated considerable success in the treatment of conditions such as Alzheimer's disease, diabetes mellitus and obesity. There are numerous works in the literature that have reported that phenolic compounds have promising cholinesterase inhibitory activities [29; 30]. Since _Hypericum_ extract is rich in phenolic compounds, it can be considered a promising AChE and BChE inhibitor. The results of our _H. perforatum_ samples showed a similar AChE and BChE inhibitory effect for all tested extracts, from 1.98 \(\pm\) 0.01 to 2.36 \(\pm\) 0.07 mg GALAE/g and from 1.35 \(\pm\) 0.12 to 1.86 \(\pm\) 0.18 mg GALAE/g, respectively. Samples exhibited moderate inhibitory activity for both \(\alpha\)-glucosidase and \(\alpha\)-amylase, according to the data of [PERSON] et al. [31]. In particular, we detected smaller values in terms of \(\alpha\)-amylase inhibition for extracts than \(\alpha\)-glucosidase inhibition. The samples were also tested for their capacity to inhibit the tyrosinase enzyme. The extracts derived from the full bloom harvested plants have a greater tyrosinase inhibitory activity than that observed for the other extract, obtained from sample III (harvested at late flowering maturity). In particular, the extract of _H. perforatum_ with higher tyrosinase inhibitory activity showed a value of 52.49 \(\pm\) 2.31 mg KAE/g. [PERSON] et al. [12] obtained similar results with the highest enzyme inhibitory properties in _H. perforatum_ L., originating from the Republic of Macedonia. Overall, _H. perforatum_ extracts displayed encouraging biological activities, which warrant further investigations aimed at developing biopharmaceuticals. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Samples**} & **DPPH** & **ABTS** & **CURRAC** & **FRAP** & **Chel. ab.** & **Pho.** \\  & **(mg TE/g)** & **(mg TE/g)** & **(mg TE/g)** & **(mg TE/g)** & **(mg EDTAE/g)** & **(mmol TE/g)** \\ \hline _H. perforatum_ & & & & & & \\ I & 171.40 \(\pm\) 2.73 a & 363.58 \(\pm\) 5.82 a & 386.92 \(\pm\) 12.97 a & 207 \(\pm\) 6 a & 15.13 \(\pm\) 0.4 b & 2.35 \(\pm\) 0.17 a \\ _H. perforatum_ & & & & & & \\ II & 159.45 \(\pm\) 0.44 b & 310.33 \(\pm\) 6.9 b & 315.63 \(\pm\) 14.8 b & 194.98 \(\pm\) 2.65 b & 12.96 \(\pm\) 0.35 c & 2.49 \(\pm\) 0.04 a \\ _H. perforatum_ & & & & & & \\ III & 62.19 \(\pm\) 0.32 c & 160.97 \(\pm\) 2.97 c & 143.99 \(\pm\) 1.64 c & 75 \(\pm\) 3.46 c & 19.65 \(\pm\) 0.5 a & 1.86 \(\pm\) 0.12 b \\ \hline \hline \end{tabular} Values expressed are means \(\pm\) S.D. of three parallel measurements. TE: Trolox equivalent; EDTAE: EDTA equivalent. Chel. ab., Chelating ability; Pho., Phosphomolybdenum. Different letters indicate significant differences between the tested extracts (\(p<\) 0.05).  
\end{table} 
Table 4: Antioxidant properties of the tested extracts.