Evaluation of Biologically Inspired Ammonium Xanthommatin as a Multifunctional Cosmetic Ingredient.

We describe the investigation of an organic natural product, ammonium xanthommatin (Xanthochrome), in a series of studies designed to not only assess its impact on endocrine receptor function in vitro but also interrogate its mutagenic potential using bacterial reverse mutation assays. As a multifunctional raw material, ammonium xanthommatin functions as an antioxidant with a broad absorption profile spanning the UV through the visible spectrum, making it an interesting target for cosmetic applications. In solution, ammonium xanthommatin contributes to <30% inhibition of hormonal activities, indicating that it is not an endocrine disruptor. Furthermore, the compound does not cause gene mutations in the bacterial strains used, indicating that it is nonmutagenic. Applications are also described, highlighting xanthommatin's ability to boost the UVA and UVB absorptive properties of traditional chemical UV filters by >50% across all filters tested. In addition to these features, xanthommatin exhibited no phototoxic hazards in vitro when irradiated with UVA and visible light, demonstrating its utility as a multifunctional cosmetic ingredient. Although these findings encourage the use of xanthommatin in cosmetics, they represent only the beginning of the complete in vitro and in vivo data package needed to support safety and efficacy claims for future applications in skin health.