Green extraction of Rosa canina L. and Prunus spinosa L. by NaDES and their encapsulation in chitosan nanoparticles for cosmetic industry

The cosmetic industries increasingly value innovative natural ingredients as markers of sustainability. This work investigated the preparation of extracts from rosehips and blackthorns using natural deep eutectic solvents (NaDES) and their encapsulation in chitosan nanoparticles for cosmetic applications. The phenolic composition of the extracts, obtained either using ethanolic solution or NaDES, was evaluated through phytochemical assays. Chitosan nanoparticles were prepared using various crosslinking agents and polymer concentrations, followed by characterization of their physicochemical properties. Cell viability studies were conducted on the human dermal fibroblast cell line WS1. The NaDES extracts exhibited promising results, showing a total phenolic content of 35.26±2.41 and 8.65±0.42 mg GAE/g FW and antioxidant activity by DPPH assay of 92.67±0.74 and 86.06 ±1.88 % for rosehip and blackthorn, respectively. The optimized nanoparticles formulation was achieved using pentasodium tripolyphosphate solid as the crosslinking agent and a chitosan concentration of 2 mg/mL. Nanoparticle characterization revealed that they were small in size with entrapment efficiency of 63.43±0.54 and 72.64±0.68 % for rosehips and blackthorns extract, respectively. Furthermore, the chosen formulations were stable for 8 weeks and exhibited good cell viability. In conclusion, chitosan nanoparticles loaded with NaDES extract of rosehip and blackthorn could be a novel and green antioxidant formulation for cosmetic application.