## 3 Results and Discussion
### Antioxidant Activity Evaluation
#### 3.3.2 Determination of Antioxidant Activity by the Electrochemical Method  
The determination of the antioxidant capacity of the studied samples was made using as a reference the antioxidant capacity of Trolox, as it had previously been obtained. The methodology used was the same for all samples, with one exception for each sample: after recording the DPPH voltammogram, a 10 \(\upmu\)L sample was introduced into the system and the voltammogram corresponding to the addition was recorded again. The readings for each sample were made at time zero and at 2 min. Figures S5-S10 in the Supplementary Materials File show the behaviors of the samples with respect to the long-living radical DPPH at the times established as optimal for measurement. From Figures S5-S10, it is obvious that all the analyzed samples have some antioxidant properties that can be explained by the important content of polyphenic derivatives, including flavones, catechols, ODPs, proanthocyanosides, and anthocyanins. This method reports on the total antioxidant capacity of the extracts, and no fractional separation of the components in the mixture was performed. After recording the voltammograms, the peak current intensities corresponding to each sample were read and the differences were determined at 0 and 2 min from the peak current intensity belonging to DPPH in the absence of any antioxidant. The results are presented in Table 7.  
Equation (5) was used to determine the antioxidant capacity of the samples:  
\[AC_{sample}=V_{sample}\times K\times\frac{i_{sample}-i_{blank}}{i_{Trolox}-i_{ blank}} \tag{5}\]  
where \(V\) is the sample volume, \(K\) is the dilution factor of the sample, \(i_{sample}\) is the intensity of the anodic peak current of the DPPH in the presence of the sample, \(i_{blank}\) is the peak current intensity of DPPH in the absence of any antioxidant, and \(i_{Trolox}\) is the peak current intensity of DPPH in the presence of Trolox. The obtained values are presented in Table S3 in the Supplementary Materials File and Figure 4.  
Figure 3: Variation in antioxidant activity values as a function of the reaction time for the studied solutions. The obtained data were verified by UV-VIS spectrometry, and we observed the changes in the absorption maxima of DPPH from 519 nm. The spectrometric determinations for _Myrtilli fructus, Cynosbati fructus_, and the antioxidant product, however, were inconclusive since the extracts have absorption maxima in the region of 500-520 nm, which made it difficult to monitor possible changes in the maximum DPPH. In the case of _Medicaginis herba, Trifolini pratense forces_, and _Ginkgo bilobae folium_, to which the method could be applied, the antioxidant capacity was calculated according to Equation (6):  
\[AC_{sample}=V_{sample}\times K\times\frac{A_{sample}-A_{blanck}}{A_{Trolax}-A_{ blanck}} \tag{6}\]  
where \(AC_{sample}\) is the antioxidant capacity of the sample, \(V\) is the sample volume, \(K\) is the sample dilution factor, \(A_{sample}\) is the absorbance of DPPH in the presence of the sample, \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Sample** & **I\({}_{DPPH}\) (mA)** & **Time (Minutes)** & **Intensities** \\ \hline _Medicaginis herba_ & 2.330 & 0 & 0.487 \\  & 2.070 & 2 & 0.701 \\ \hline _Trifolini pratense forces_ & 2.261 & 0 & 0.317 \\  & 2.338 & 2 & 0.437 \\ \hline _Ginkgo bilobae folium_ & 2.461 & 0 & 0.861 \\  & 2.292 & 2 & 1.03 \\ \hline _Myrtillis fructus_ & 1.896 & 0 & 0.207 \\  & 1.892 & 2 & 0.211 \\ \hline _Cynosbati fructus_ & 1.890 & 0 & 0.220 \\  & 1.887 & 2 & 0.236 \\ \hline _CILTAG_ & 2.461 & 0 & 0.861 \\  & 2.287 & 2 & 1.100 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: The values of the anodic peak current intensities of DPPH in the presence of hydroalcoholic solutions of _Medicaginis herba, Trifolini pratense forces, Ginkgo bilobae folium, Myrtilli fructus_, and _Cynosbati fructus_ and CILTAG.