# White Grape Ponace Valorization for Remediating Purposes
## 3 Results
### Antioxidant and Antiradical Activity  
Figures 2 and 3 show that all samples have antiradical activity independent of the pretreatment applied. The effect is present even at the lowest aqueous extract concentration. In the case of these samples, the process seems to be influenced by the temperatures used at the minimum concentration in the experiments; only the refrigerated samples present antiradical activity. Figure 1: Total phenol content. For the evaluation of the antioxidant activity, we used the IC 50 parameter, which refers to the necessary concentration of antioxidant that reduces the DPPH concentration by 50%. A low value for IC 50 corresponds with a higher antioxidant capacity. According to the data presented in Table 2, the most efficient extraction, in terms of half of the maximum inhibitory concentration, was obtained in the case of dried samples in alcoholic media. It can be observed that despite the highest content of phenolic compounds in the lyophilized extracts, the IC 50 does not reveal the same. This behavior might be due to the presence of phenolic compounds with weak radical-scavenging activity in the lyophilized extracts, but further studies are necessary to prove this assumption. Figure 3: DPPH* scavenging activity at different pomace concentrations in water. PRE-aqueous extract of refrigerated pomace; PDE-aqueous extract of dry pomace; PLE-aqueous extract of lyophilized pomace; PLU-aqueous ultrasound macerate of lyophilized pomace; PLS-aqueous-stirred macerate of lyophilized pomace. Figure 2: DPPH* scavenging activity at different pomace concentrations in ethanol-water. PRE-hydroalcoholic extract of refrigerated pomace; PDE-hydroalcoholic extract of dry pomace; PLE-hydroalcoholic extract of lyophilized pomace; PLU-hydroalcoholic ultrasound macerate of lyophilized pomace; PLS-hydroalcoholic stirred macerate of lyophilized pomace. As shown in Figures 4 and 5, the water-obtained extracts exhibit lower activity in ABTS-scavenged radicals than the extracts obtained in the mixture of ethanol and water. For the hydroalcoholic extracts, in the case of ABTS-scavenging activity, it is necessary to have a higher concentration of the extracts than that exhibited for the DPPH radicals. In the case of the concentrations of the extracts ranging between 0.0625 and 0.25, no ABTS-scavenging activity could be detected. Also, the lyophilized extract had the same behavior in aqueous media. Figure 4: ABTS* scavenging activity at different pomace concentrations in ethanol-water. PRE-hydroalcoholic extract of refrigerated pomace; PDE-hydroalcoholic extract of dry pomace; PLE-hydroalcoholic extract of lyophilized pomace; PLU-hydroalcoholic ultrasound macerate of lyophilized pomace; PLS-hydroalcoholic stirred macerate of lyophilized pomace. Figure 5: ABTS* scavenging activity at different pomace concentrations in water. PRE-aqueous extract of refrigerated pomace; PDE-aqueous extract of dry pomace; PLU-aqueous ultrasound macerate of lyophilized pomace; PLS-aqueous-stirred macerate of lyophilized pomace. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Sample, [mg/mL]** & **Ethanol-Water** & **Water** \\ \hline PRE & 0.055 & 0.192 \\ PDE & 0.045 & 1.545 \\ PLE & 0.166 & 0.388 \\ PLS & 0.785 & 4.395 \\ PLU & 0.709 & 7.238 \\ \hline \hline \end{tabular} \({}^{\dagger}\)IC 50: Half of the maximum inhibitory concentration.  
\end{table} 
Table 2: IC 50 \({}^{\dagger}\) values for DPPH* scavenging activity. The medium inhibition concentration in the case of ABTS**++** scavenged radicals shows 10 times higher values than the one obtained in the case of DPPH(Table 1) scavenged radicals, as shown in Table 3. Comparable values present the lyophilized samples and the refrigerated samples. As observed in Figures 6 and 7, the extract's superoxide radical-scavenged activity is presented in concentrations of 100 times lower compared with the previous determinations. The best results are obtained for the refrigerated extracts in alcoholic and aqueous media.