Our client wanted help to understand the antioxidant potential of 5 different cosmetic active ingredients, to help formulate an optimal anti-ageing skincare product.
This case study shows how our in vitro test works and how we demonstrated which concentration and combination of active ingredients produced the most significant antioxidant activity.
ABSTRACT
Anti-oxidant activity forms a vital part of the body’s natural defence system against reactive oxygen species (ROS), which are formed as a by-product of metabolism and can be harmful to cells. ROS levels in the skin are increased dramatically by a variety of internal and external factors including stress, the ageing process and exposure to air pollutants. Antioxidant cosmetic ingredients may therefore support a variety of claims including anti-pollution and anti-ageing and have gained significant popularity.
The OxiSelect™ test measures antioxidant activity against hydroxyl, peroxyl and other ROS in human skin cell (epidermal keratinocyte) cultures, indicating the potential of active cosmetic ingredients to protect against the effects of ageing and pollution. The aim of this study was to assess the antioxidant potential of five active ingredients (designated codes A, B, C, D, E), alone and in combination (A+B; A+C; A+B+C; A+B+D; A+B+E in equal concentrations). Two different concentrations (0.01% and 0.05%) of each test item and combinations were tested and compared to the untreated negative control (NC) and positive control (quercetin).
The results placed the 10 conditions into a rank order of activity, and demonstrated that all test items at the highest concentration (0.05%) have antioxidant properties. Ingredient B was the most potent of the five, and its activity was further increased when used in combination with ingredients A and E together, demonstrating a synergistic effect. The results were used to create a cosmetic formulation (anti-ageing skincare product) with optimal antioxidant activity.
