Capacidade antioxidante e potencial fotoprotetor do extrato etanólico das fibras de cascas de coco (Cocos nucifera L. ((Arecaceae)

Abstract

Chronic exposure to the sun, coupled with lack of sun protection, represents one of the highest risks to premature skin aging and cancer development. Plant extracts contain bioactive substances that have antioxidant action and can absorb UV radiation, at certain wavelengths. These extracts have been employed in sun protective formulations. The species Cocos nucifera L. presents in its composition, phenolic compounds, which confer it, antioxidant properties, and photoprotective action. Thus, the objective of the present work was to evaluate the ethanolic extracts of the yellow dwarf coconut husk fibers, regarding its total phenol content – CTF, antioxidant capacity (by DPPH● and FRAP assays and superoxide scavenging activity) and photoprotective potential (UVB) (FPS). In addition, the development of photoprotective formulations containing different concentrations of the extracts incorporated into Lanette base cream (5-20% m/m) was evaluated for photoprotective potential (SPF). The extract's total phenol content was 673.9 mg gallic acid equivalents (EAG) g-1 dry extract. The antioxidant capacity was 74.9% for the ability to scavenger DPPH● radical and 3287 μmol Trolox equivalents (ET) g-1 of dry extract. For superoxide radical scavenger activity, the value of IC50 of the extract was 6.6 μg mL-1. Toward UVB protection potential, the extracts were also photoprotective with SPF values equivalent to the standard benzophenone-3. The formulations prepared from the extracts incorporated in Lanette base cream had shown maximum SPF values of 16,20. The results obtained demonstrate that the ethanolic extracts from coconut husk fibers have biotechnological potential and can be active ingredients in cosmetic and/or pharmaceutical formulations.