New oils for cosmetic o/w emulsions: In vitro/ in vivo evaluation

Abstract

The aim of this study was to design new cosmetic formulations containing oils from catolé, licuri and spent coffee grounds, and to evaluate their immediate and long-term effects on skin barrier function and skin hydration. Nonionic oil-in-water (o/w) emulsions were prepared and physicochemically characterized. The effects of the formulations were assessed by volunteers and by measuring the water content of the epidermis (WCE) and transepidermal water loss (TEWL) both two hours and 20 days after daily application. The irritation potential was evaluated using three different methods: the Hen's egg chorioallantoic membrane test (HET-CAM); the observation of undesirable effects after skin formulation application, and by using the L*a*b* system to verify changes in skin coloring. The results obtained showed that the formulations containing 10% of these oils presented promising characteristics in the improvement of hydration and skin barrier function when compared to the baseline values and with the placebo cream. According to the sensory evaluation performed, all creams were found to have great acceptability.