Eco-friendly insights on kiwiberry leaves valorization through in-vitro and in-vivo studies

On the last decade, the demand for novel active skin ingredients based on sustainable principles arise as a trend. These new concerns transformed the consumer preferences, which are not actually solved by the industry portfolio. Regulatory aspects establish guidelines to assess the safety and efficacy of new cosmetic ingredients, being this step imperative to introduce a new ingredient on the market. Our last studies reported the richness of Actinidia arguta (kiwiberry) leaves in bioactive compounds with potential skin applications, but further studies are necessary to validate this extract. Therefore, the current study aimed to screen the hydroalcoholic extract of A. arguta leaves regarding elastase and hyaluronidase inhibition, achieving excellent results (65.62 ± 2.09% and 54.64 ± 4.17%, respectively). The cell viability was assessed in keratinocytes and fibroblasts (0.1–1000 μg/mL), ensuring the absence of cytotoxic effects. Afterwards, 3D models, namely a skin (EpiSkin™) and an ocular (SkinEthic™ HCE, respectively) model, were used to estimate the irritant potential. The viability achieved in both models after exposure to the extract was, respectively, 55.18 ± 10.60% and 101.15 ± 5.96%. The IL-1α released for the skin and ocular models were, respectively, 0 pg/mL and 35.60 ± 2.61 pg/mL, being the extract classified as non-irritant for both models. Lastly, in-vivo studies performed through a patch test in 10 human volunteers proved the absence of allergic or irritative reactions. Overall, the results attained highlighted that the hydroalcoholic kiwiberry leaves extract is an excellent cosmetic ingredient, being not irritant to skin application.