o:37288 Chemical Characterization and Cytotoxic Profile of Cocoa Bean Shell (Theobroma cacao L.) extract as a Potential Cosmetic Ingredient en The cocoa bean shell (Theobroma cacao L.) represents a significant by-product of the confectionery industry, generated during the removal of the outer seed coat after the roasting process and accounting for approximately 12–20% of the total bean mass. Traditionally treated as waste, this biomass is increasingly recognized as a secondary raw material suitable for valorization across various industrial sectors, including food, cosmetic, and biotechnological applications. Such an approach aligns with the principles of the circular economy, which emphasize closing material loops through waste reduction, reuse, and resource recycling, thereby improving both environmental performance and the economic efficiency of production systems. In the present study, extraction of the cocoa bean shell was carried out using aqueous Soxhlet extraction. The obtained extract was chemically characterized through the determination of total polyphenol content (TPC), total flavonoid content (TFC), antioxidant capacity (DPPH and ABTS methods), and sun protection factor (SPF). TPC, determined using the Folin-Ciocalteu method, amounted to 8.13±0.59 mg gallic acid equivalent/100 mg of dried extract, while TFC was 2.37±0.05 mg catechin equivalent/100 mg of dried extract. The IC50 value (the concentration of the extract required to neutralize 50% of free DPPH radicals) was 4.05±0.02 mg/mL, and the anti-ABTS potential was 28.89±3.11 mmol Trolox equivalent/g of dried extract. SPF, determined using the in vitro spectrophotometric method and the Mansur equation, varied in the range of 0.94-21.40, depending on the tested concentration of the extract (175-3000 µg/mL). Cytotoxicity of the extract was assessed using the MTT (3-(4,5 dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on human fibroblasts (MRC-5). The starting extract concentration of 21.1 mg/mL was diluted in medium to 2×, 4×, 8×, 16×, 32×, and 64×. Significant cytotoxicity was observed at 2× and 4× dilutions (p < 0.001), partial recovery of cell viability at 8× (p < 0.001), a mild but significant effect at 16× (p < 0.05), while 32× and 64× dilutions showed no statistically significant effect compared to the control (p > 0.05), indicating the absence of cytotoxicity at these concentrations. One-way ANOVA (F = 449.6; p < 0.0001) confirmed significant differences between treated groups. Dunnett’s post hoc test was used to compare each treatment with the control. These findings highlight the notable potential of cocoa bean shell extract as a natural antioxidant and auxiliary UV filter for incorporation into cosmetic formulations. 1552100 978-86-80321-40-0 2025-12-12T15:32:25.312Z 44 yes 46 Sandra Rakin University of Belgrade, Institute for the Application of Nuclear Energy, Serbia master inženjer tehnologije/hemijski inženjer 0009-0007-4016-3882 Aleksandra A. Jovanović University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor tehnoloških nauka person 0000-0001-5394-0125 Milica Jovanović Krivokuća University of Belgrade, Institute for the Application of Nuclear Energy INEP, Serbia doktor bioloških nauka person 0000-0001-8292-4853 Maja Bulatović University of Belgrade, Faculty of Technology and Metallurgy, Serbia person Danica Zarić University of Belgrade, Innovation Centre of the Faculty of Technology and Metallurgy, Serbia person Marica Rakin University of Belgrade, Faculty of Technology and Metallurgy, Serbia person application/pdf 1059543 https://phaidrabg.bg.ac.rs/o:37288 no yes 19 70 92000005 11A29 11A41 Chemical Characterization and Cytotoxic Profile of Cocoa Bean Shell (Theobroma cacao L.) extract as a Potential Cosmetic Ingredient 50 Book of Abstracts of the 23rd Young Researchers' Conference, Materials Science and Engineering Kneza Mihaila 35/IV, 11000 Belgrade, Serbia Institute of Technical Sciences of SASA 2025