Chronic exposure to solar radiation could contribute to premature skin aging and skin cancer. Skin
presents its own antioxidant defense, however when defenses are out of balance, reactive oxygen species
could damage biological structures. In the present work, an oil-in-water photoprotective emulsion was
developed and Bauhinia microstachya var. massambabensis Vaz, Fabaceae, extracts at 1% (obtained by
extraction with different solvents) were added to this emulsion. In vitro and in vivo efficacy and safety of
the formulations were evaluated. Spectrophotometric methods and in vivo Colipa test were performed
to evaluated efficacy of the formulations, through sun protection factor (SPF) determination and UVA
protection factor assessment. To the in vitro safety assessment HET-CAM, CAM-TBS and Red Blood Cell
tests were performed. Results showed that both extracts contributed to a higher in vivo photoprotection
(SPF 18) when compared to the formulation without extract(SPF 13),this result could be attributed to the
antioxidant activity of the plant extracts that act by capturing reactive oxygen species. Concerning safety,
all formulations were considered non-irritant according to in vitro tests. Formulations containing extracts
could be considered efficient and safe for cosmetic use since they presented higher sun protection factor
and passed the toxicity tests.