*Article* **Antioxidant E**ff**ect of Cocoa By-Product and Cherry Polyphenol Extracts: A Comparative Study**

**Francesca Felice 1,\*, Angela Fabiano 2, Marinella De Leo 2,3, Anna Maria Piras 2, Denise Beconcini 2, Maria Michela Cesare 1,4, Alessandra Braca 2,3, Ylenia Zambito 2,3 and Rossella Di Stefano 1,3**


Received: 17 December 2019; Accepted: 31 January 2020; Published: 3 February 2020

**Abstract:** Background: Recent studies have highlighted the importance of cherry and cocoa extracts consumption to protect cells from oxidative stress, paying particular attention to cocoa by-products. This study aims to investigate the protective effect of cocoa husk extract (CHE) and cherry extracts (CE) against ROS-induced oxidative stress in Human Umbilical Vein Endothelial Cells (HUVECs). Methods: CE and CHE had antioxidant activity characterized by total polyphenols content (TPC). HUVECs were treated for 2 h and 24 h with increasing TPC concentrations of CE and CHE (5-10-25-50-100 μg Gallic Acid Equivalent (GAE)/mL) and then with H2O2 for 1 h. Cell viability and ROS production were evaluated. CE and CHE polyphenols permeability on excised rat intestine were also studied. Results: CE and CHE showed a similar antioxidant activity (2.5 <sup>±</sup> 0.01 mmol Fe<sup>2</sup>+/100 g FW (fresh weight) and 2.19 <sup>±</sup> 0.09 mmol Fe2+/100 g FW, respectively, *<sup>p</sup>* <sup>&</sup>gt; 0.05) whereas CHE had a higher TPC (7105.0 ± 96.9 mg GAE/100 g FW) than CE (402.5 ± 8.4 mg GAE/100 g), *p* < 0.05. The in vitro viability assay showed that both extracts were non-cytotoxic. CHE resulted in protection against ROS at lower concentrations than CE. CHE showed a 2-fold higher apparent permeability compared to CE. Conclusions: CHE represents a high-value antioxidant source, which is interesting for the food and pharmaceutical industries.

**Keywords:** cocoa by-products; cherry extract; oxidative stress; human endothelial cell
