## 6 Grape and Winery By-Products: Active Ingredients in Cosmeceuticals
### Antioxidant
Catechins, which also exhibit antioxidant activity [89], were present in varying amounts across the extracts, with the Marselan variety showing the highest concentration. Similarly, other antioxidants such as chlorogenic acid, caffeic acid, and p-coumaric acid were most abundant in the Marselan extract. \begin{table}
\begin{tabular}{p{113.8 pt} p{113.8 pt} p{113.8 pt} p{113.8 pt}} \hline \hline
**Hypothesis-Intervention** & **Study Design-/Parameters Examined** & **Main Findings** & **Year of Study** & **Ref.** \\ \hline The purpose of this research was to formulate a facial motivating own containing phenolic center and oils from grape pome and grapeseeds, and to evaluate its antioxidant and its ability & * The antioxidant capacity was determined by the DPPH method. & * Both extracts and oils show antioxidant properties, with extracts showing higher levels. & * \\ \hline This study investigated the efficacy and safety of grape pome for application as an antioxidant raw material in cosmetics & * The extracts were tested in cell line 3T3 (fibroblasts) with cytotoxicity. & * The extracts were safe at high concentrations. & * \\ \hline \multirow{2}{*}{The aim of this study was to examine and evaluate seed extracts of different grape cosmetics with antioxidants in the extracts.} & * The composition of the extracts was determined by HPLC. & * HPLC analysis confirmed the presence of & * \\ \cline{2-3} This study investigated the efficacy and safety of grape pome for application as an antioxidant raw material in cosmetics & * The extracts were tested in cell line 3T3 (fibroblasts) with cytotoxicity. & * The extracts were safe at high concentrations. & * \\ \cline{2-3} in cosmetics & * Study of the cyyptoctive effect of the extract at a lower concentration. & * There was significant cyyptoc protection from & * \\ \cline{2-3} Analysis of SEM. & * Analysis of SEM. & * Oxidative damage in fibroblasts. & * \\ \hline \multirow{4}{*}{The aim of this study was to examine and evaluate seed extracts of different grape cosmetics with antioxidant activity} & * TPC was measured by the Poincaré-Ciocalute method and pronthocyanantilus were identified by the & * Phenolic content and proanthocyanin content & * \\ \cline{2-3}  & * & 4-dimethyl/aminoaminoaldehyde reduction. & * were higher in two of the varieties. & * \\ \cline{2-3}  & * & & * High levels of polyphenols (gallic acid, & * \\ \cline{2-3}  & * & & *ductions, chlorogenic acid, & * \\ \cline{2-3}  & * & & * p-comamic acid) were found in some of & * \\ \cline{2-3}  & * & & * Various percentages of an extract were incorporated into cosmetic & * \\ \cline{2-3}  & * & & * creams and stability tests were carried out for 4 months. & * \\ \hline \hline \end{tabular}  
* In vitro tests exposing cells to reactive oxygen species and measuring the reduction of oxidative stress.
* Enzyme measurement evaluating levels of antioxidant enzymes such as SOD, CAT, and GPs.
* Dose-response tests observing the effects of polyphenols at different concentrations.  
\end{table} 
Table 4: Antioxidant properties. The antioxidant capacity of the extracts was evaluated using three methods: DPPH (2,2-diphenyl-1-picrylhydrazyl), CUPRAC (cupric ion reducing antioxidant capacity), and FRAP (ferric reducing antioxidant power). As anticipated, the Marselan extract demonstrated the highest antioxidant activity, correlating with its elevated levels of phenolic compounds and proanthocyanidin [3]. Another study investigated the antioxidant properties of grape pomace polyphenols through a series of in vitro experiments. Grape pomace extracts were tested on cellular models exposed to reactive oxygen species (ROS), revealing a significant reduction in oxidative stress. Antioxidant enzyme activity, including superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), was evaluated, demonstrating an upregulation in response to GP polyphenols. Dose-response experiments confirmed that the antioxidant effect was concentration-dependent, with higher doses yielding enhanced ROS scavenging and enzyme activation.