Figure 5.

A, Setup for the irradiation of cultured cells under sunscreen protection. During irradiation, culture plates were covered by PMMA plates without1 or with2, 3 sunscreen SPF 50+/ UVA‐PF 40 containing LicA applied. To mimic penetration of antioxidant into the skin, some cultures were incubated with LicA prior to irradiation.3 B, ROS formation after VIS irradiation with SPF 50+/ UVA‐PF 40 sunscreen protection and with or without LicA. Fibroblast cultures were irradiated with 150 J/cm² VIS through a PMMA plate (white bar), a PMMA plate covered with sunscreen SPF 50+/UVA‐PF 40 (gray bar) or a PMMA plate with the same sunscreen applied and additionally 2 µmol/L LicA in the culture medium (black bar), respectively. Significant differences were marked (***P < .001). An Oriel 1600 W Solar Simulator filtered for VIS irradiation was used. C, Mean carotenoid levels after irradiation relative to initial values measured in vivo in the skin. Prior to irradiation with blue light (100 J/cm²), for the spectrum of the Skintrek^® PT3 filtered for UV irradiation see Figure S3 in Appendix S1, skin areas were either left untreated (white bar), or protected by a sunscreen (SPF 50+, UVA‐PF 40) containg only UV filters (gray bars) or the same sunscreen containing additionally LicA (black bar). Carotenoids in skin were measured in vivo by resonance Raman spectroscopy (n = 10; mean ± SD; *P < .05)