Multiple emulsions containing amazon oil: açaí oil (Euterpe oleracea)

Abstract

The aim of this work was to formulate O/W/O multiple containing acai oil as a model system and to evaluate their physical stability and in vivo Sun Protection Factor (SPF). Multiple are complex dispersion systems, known also as, emulsions of emulsions. These emulsion systems, have significant potential in the cosmetic industry. Euterpe oleracea Mart., Arecaceae, popularly known in Brazil as acai, is an economically important plant. Acai oil has been used as antioxidant and as anti-inflammatory activities. The multiple were prepared using a two-step procedure. The investigated formulations were characterized and their stability over time was evaluated by preliminary and accelerated stability. O/W/O multiple containing the same concentration of sunscreens with and without acai oil were evaluated by the International Sun Protection Factor Test Method. The samples containing 70% (w/w) of primary emulsion, 5% (w/w) PEG-30-dipolyhydroxystearate, 10% (w/w) of acai oil and 5% (w/w) of sucrose polybehenate have been found to be stable. The rheological measurements revealed that the samples exhibited non-Newtonian pseudoplastic flow behavior and thixotropy. To conclude, no statistical difference could be observed on the in vivo SPF to both multiple systems with or without acai oil.