New eco-sustainable approaches for the recovery of bioactive molecules from agricultural by-products and their biochemical validation for cosmeceutical application.

Nowadays, agricultural food waste poses a significant environmental challenge. Agri-food by-products, such as peels and seeds, are rich in bioactive compounds with proven health benefits, making them a valuable source of active ingredients for sustainable products. This research investigates the upcycling of pomegranate peels, tomato skins, and citrus by-products to develop innovative cosmeceutical ingredients for oral and skin care formulations. The first case study explored the biological activities of extracts derived from pomegranate peel and tomato skin using in vitro models of the oral mucosa (Human Primary Gingival Epithelial Cells). The results revealed significant antioxidant properties, due to reduced intracellular H2O2 production and enhanced Superoxide Dismutase 1 expression (p<0.01). The extracts also exhibited anti-inflammatory effects, related to the downregulation of key pro-inflammatory markers, including Tumor Necrosis Factor α (p<0.05) and Monocyte Chemoattractant Protein 1 (p<0.001). Furthermore, they displayed antibacterial properties by inhibiting the growth of Streptococcus mutans and Streptococcus sanguinis. Additionally, when included in a mouthwash formulation, the extracts maintained their efficacy, thereby underscoring their suitability for oral care applications.The second case study explored the valorization of citrus by-products, employing a sustainable Natural Deep Eutectic Solvents (NADES)-based extraction method to obtain polyphenol-rich extracts, with hesperidin as a major compound. Safety and efficacy evaluation in human keratinocytes (HaCaT) demonstrated significant antioxidant activity, characterized by a reduction in intracellular H2O2 levels (p<0.01). Notably, the extracts significantly enhanced wound healing, achieving complete wound closure within 48 hours (p<0.01). Chemokine release profiling indicated a modulation of inflammatory mediators, specifically interleukin-6 and interleukin-8 (p<0.05), supporting the observed tissue regeneration properties.This research supports the conversion of agri-food waste into high-value cosmeceutical ingredients that benefit oral and skin health. This approach aligns with circular economy principles, providing environmentally sustainable solutions while identifying novel resources for the cosmeceutical field.