Análise fitoquímica preliminar, atividade antioxidante e fotoprotectora dos extractos da casca de Tabebuia serratifolia (Vahl) G. Nicholson

Objective: In the present investigation, phytochemical screening was performed, the in vitro antioxidant and photoprotective activity of Tabebuia serratifolia bark extracts was determined. Methods: The bark extracts were obtained by maceration technique using acetone and ethanol as solvents. Standard chemical staining and/or precipitation tests were used for preliminary phytochemical analysis. Antioxidant activity was evaluated through the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay. The photoprotective effect was established by the Mansur spectrophotometric method. Results:Phytochemical analysis showed that the extracts possess alkaloids, flavonoids, phenolic compounds, quinones, coumarins, triterpenes and steroids. The total content of phenolic compounds and flavonoids for the acetone extract (TSA) was 71.54 mg gallic acid equivalents/g extract and 8.80 mg quercetin equivalents/g extract, respectively, while for the ethanol extract (TSE) it was 65.70 mg gallic acid equivalents/g extract and 8.19 mg quercetin equivalents/g extract. The mean inhibitory concentration (CI50) value of the extracts was 80.91 μg/mL for TSA and 84.25 μg/mL for TSE. The extracts had an average sun protection factor, for TSA it was 12.92 and for TSE it was 7.67. Conclusion: The results showed that Tabebuia serratifolia extracts possess a great variety of chemical compounds with antioxidant and photoprotective activity.