## 3 Results and Discussion  
### Determining Optimal Extraction Conditions  
Measurements provided the optimal conditions for achieving the highest antioxidative activity of a single material as shown in Table 1. The antioxidative activity is presented in Figure 1d. Table 1 shows optimal extraction temperatures for all materials at a temperature range from 90 \({}^{\circ}\)C to 100 \({}^{\circ}\)C, according to the experimental design in the temperature range from 40 \({}^{\circ}\)C to 100 \({}^{\circ}\)C and the time range from 5 min to 30 min. The extraction times are about 15 min, with a slightly lower optimal extraction time in the case of Horsetail extract, according to the program. A high percentage of inhibitory effectiveness (89%) in rosemary was measured (Figure 1d).  
Much research has already been done on rosemary, and it has been shown to contain many antioxidants, such as carnosol, rosamol, carnos  
\begin{table}
\begin{tabular}{c c c} \hline \hline _Material_ & \(T_{extraction}\) [\({}^{\circ}\)C] & \(t_{extraction}\) [min] \\ \hline _curcuruma (Curcuruma longa)_ & 100 & 15 \\ _goji berry (Lycium barbarum)_ & 93 & 13 \\ _grape marc and seeds (Vitis L.)_ & 100 & 15 \\ _horsetail (Equisetum arvense)_ & 100 & 6 \\ _rosemary (Rosmarinus officinalis)_ & 96 & 20 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Optimal conditions for the highest antioxidative activity.  
Figure 1: (a) Total phenolic content in selected extracts. (b) Proanthocyanidin content in selected extracts. (c) Concentrations of extracts required for 50% inhibitory effectiveness. (d) Antioxidant activity in selected extracts under optimal conditions. The extracts were obtained by maceration with water at optimum temperature and time: Curcuma (100 \({}^{\circ}\)C, 15 min), Goji berry (93 \({}^{\circ}\)C, 13 min), Grape marc and seeds (100 \({}^{\circ}\)C, 15 min), Horsetail (100 \({}^{\circ}\)C, 6 min), and Rosemary (96 \({}^{\circ}\)C, 20 min).  
perecent inhibitory effectiveness was determined for turmeric, which is assumed to be a component of curcumin. Similar results have been reported in the literature, with most being achieved with added ethanol on extraction; for example, about 70% of the antioxidant activity was achieved on extraction with 50% ethanol at 60 \({}^{\circ}\)C and a time of 60 min [91]. High values were obtained with the use of a juice extractor, with antioxidant activity of curcumin measured around 65% [92]. Grape extract achieved 84% inhibition, probably because of the high content of proanthocyanidins. The inhibitory value of horsetail extract was measured at 79%. It has been reported that horsetail extracts show high superoxide anion radical-scavenging activities [93]. Goji berries had the lowest inhibitory value, but still above 50%. In the future, it would be interesting to compare the maceration results obtained with supercritical extraction using a co-solvent (water), because supercritical water extraction has been shown to achieve high antioxidant activities. A concentration of 11.3 \(\upmu\)g/mL has been measured, corresponding to high antioxidant activities. It has also been found that at lower temperatures (25 \({}^{\circ}\)C), the main constituent of the extract is a more polar compound (rosmanol). By increasing the temperature to 200 \({}^{\circ}\)C, carnosic acid, carnosol, genquaninin, and carnosic acid have been extracted at 200 \({}^{\circ}\)C [90]. Studies show the key impact of different extraction methods on purity, molecular characteristics and biological properties, even in the case of extracted alignates [94]. For example, curcumin-laden alginate--80 nanoparticle polysorbate may be useful in treating various human inflammatory diseases [95].