Synergistic photoprotective activity of nanocarrier containing oil of Acrocomia aculeata (Jacq.) Lodd. Ex. Martius-Arecaceae

Nanostructured vegetable oils have played a key role towards a major shift in sunscreen formulation. The organic ultraviolet filters, present in conventional products, can be absorbed through the skin resulting in systemic exposure with unpredicted effects. Thus, the long-term exposure to these chemical agents may pose a risk to consumer safety and health. Additionally, structural change or degradation of organic filters such as avobenzone may occur by the ultraviolet radiation (UVR) decreasing its absorption capacity. Nevertheless, the use of these products, at daily basis, is highly recommended for skin cancer and photoaging prevention. The bocaiúva oils contain a high content of fatty acids, polyphenols, oligo-elements and β-carotene. This feature has potential application as a natural effective strategy against the UVR. In the present study, nanostructured lipid carriers (NLCs) have been prepared by high-pressure homogenization technology using bocaiúva almond (BAO) and pulp (BPO) oils and cetyl palmitate, as liquid and solid lipids, respectively. The designed NLCs showed average diameters between 106.9 ± 1.6 and 188.4 ± 2.2 nm and zeta potential higher than 30 mV (in module). The NLC containing BAO (NLC-BAO) and BPO (NLC-BPO) presented avobenzone (AVO) entrapment efficiency (EE) of 75.2 and 33.3% w/w, respectively. Both NLCs presented similar EE for octocrylene (OCT): 82.3 and 82.5% w/w. NLC-BAO, co-loaded with the UV filters, allowed the increase in sun protection factor (SPF) of approximately 2-fold, from 14.1 ± 0.7 to 31.8 ± 0.6, after its incorporation into a hydrophilic cream base SPF 14. Surprisingly, NLC-BAO, without AVO and OCT, shifted the SPF of this cream base to 27.7 ± 0.8. Thus, NLC-BAO has the potential to replace organic filters preserving the photoprotection. This study shows a successful development of a nanocarrier containing bocaiúva almond oil to improve the formulation photoprotective activity. It can be a potentially superior alternative adjuvant to sunscreen products allowing the use of the renewable vegetable source.