Grape seed extract (GSE) contains a high content of polyphenols that prevent the generation of reactive oxygen species which suggests an anti-aging action. The aims of this study were to investigate the antioxidant effects of GSE, ultraviolet (UV) and visible spectrums, and in vitro sunscreen efficacy. The results showed that GSE possessed DPPH free radical scavenging capacity at an IC50 of 33.17±1.87 μg/mL and ferric reducing power of 1 mg/mL. GSE was equivalent to 4.17±0.23 mM vitamin C and 0.73±0.04 mM Trolox. Moreover, 3% and 5% w/w GSE absorbed broad UV and blue light spectra to a sufficient extent. The sun protection factor (SPF) and persistent pigment darkening (PPD) increased to 5 units and 1 unit, respectively, after addition of 3% GSE to an over-the-counter brand product. In conclusion, GSE possessed antioxidant activity and boosted the SPF/PPD value of sunscreen product. Therefore, GSE can be a value-added component to sunscreen products.
