In vitro assessment of antioxidant and photo-protective activities of essential oils for cosmetic formulations

Ultraviolet (UV) radiation is a major contributor to skin aging and damage. This study aimed to evaluate five essential oils (ginger, basil, tea tree, rosemary, and palmarosa) as potential natural alternatives or complements to organic ultraviolet filters, focusing on their in vitro sun protection factor (SPF), antioxidant activity and safety profile. Ginger oil, showing the most promising results, was selected to be incorporated (at 1% and 5% w/w) into oil-in-water (O/W) emulsions whosein vitro SPF values, technological and sensory properties were compared with the same vehicle containing Octyl Methoxycinnamate, the most commonly used organic UV-filter. Emulsions with 1% and 5% ginger oil showed suitable technological and sensory properties, although the 5% formulation had a stronger fragrance less appreciated by panelists. Overall, ginger essential oil, particularly at 5%, demonstrated significant antioxidant activity and moderate SPF, suggesting its potential use as a complementary ingredient alongside conventional UV filters to develop safer sunscreen formulations.