Antioxidant properties evaluation of topical astaxanthin formulations as anti‐aging products

BACKGROUND: The reactive oxygen species lead to skin aging via oxidative damage that are induced by UV radiation. Therefore, topical formulations which have antioxidant effect could reduce aging level. Astaxanthin is an antioxidant substance. AIMS: The aim of this study was to investigate antioxidant activity and cytotoxicity potential of the astaxanthin-loaded gel formulations. METHODS: Astaxanthin-loaded oleoresin and algae extract were used as natural active materials. The lipogel and hydrogel of these natural materials were prepared as anti-aging formulations. The formulations were characterized via parameters such as, pH, rheological analysis, mechanical properties, and stability. And also in vitro release experiments of the formulations were carried out. The antioxidant activity and cytotoxicity test were performed. RESULTS: The results of characterization studies confirmed the formulations suitable for topical application. After 24 hours, 99 μg, 88.3 μg, 403 μg, and 234.8 μg of astaxanthin released through oleoresin lipogel, oleoresin hydrogel, algae extract lipogel, and algae extract hydrogel, respectively. It was found by the cytotoxicity tests that astaxanthin is more proliferative in lipogel formulations compared to hydrogel formulations. And finally, the highest antioxidant activity was found in the algae extract hydrogel and algae extract lipogel formulation, respectively (P < .05). CONCLUSIONS: Topical formulations of astaxanthin-loaded oleoresin and algae extract were prepared successfully. At the same time, according to antioxidant activity and release studies, algae extract loaded could be suggested as topical anti-aging formulations.