## 2 Materials and Methods
### Photoprotection Activity  
A 3T3 cell line (DSMZ-ACC 173, mouse fibroblasts) was grown and maintained according to supplier's instructions. The cytotoxicity of the extracts was evaluated using the neutral red method described by [PERSON] et al. with slight modifications [17]. The 96-well microplates containing 5 \(\times\) 10\({}^{4}\) cells/well were incubated at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\) for 24 h in Dulbecco's modified Eagle medium (DMEM) (Sigma, Darmstadt, Germany), 10% FBS (Biowest, Nuaille, France). Cells were treated for 24 h with extracts (1:1 in DMEM, 10% FBS). A dose-response evaluation with eight different concentrations of each extract was performed (0.01, 0.062, 0.125, 0.25, 0.5, 1, 2 and 4 mg:mL\({}^{-1}\) in phosphate-buffered saline [PBS]) in order to find the non-cytotoxic concentrations for the cells. After the incubation period, the medium was removed by aspiration and washed with 100 \(\mu\)L of PBS. After that,100 \(\mu\)L of DMEM with 5% FBS, without phenol red and supplemented with neutral red (40 \(\upmu\)g\(\cdot\)mL\({}^{-1}\) in PBS) (Sigma, Darmstadt, Germany), was added to each well to assess cell viability. The microplates were incubated at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\) for 4 h and then washed with PBS. After aspiration, 100 \(\mu\)L of desorption solution containing glacial acetic acid, ultrapure water and absolute ethanol (1:49:50) was added and the microplates were agitated until complete homogenization. The absorbance was read at 540 nm wavelength in a microplate spectrophotometer (Epoch2, BioTek, Winooski, VT, USA). PBS supplemented with the respective concentration of DMSO (vehicle) present in each sample and DMEM medium were used as controls. Data presented are the result of 3 independent replicas.  
Knowing the non-cytotoxic concentrations of each extract, the concentration closest to 100% of cell viability was selected to perform a phototoxicity assay. The same 3T3 cell line was used and the assay was performed according to the OECD \"Guidelines for Testing of Chemicals-In Vitro 3T3 NRU Phototoxicity Test\" [18], with slight modifications. For the photoprotection evaluation of the extracts against UV radiation, the 96-well microplates containing 5 \(\times\) 10\({}^{4}\) cells/well were incubated at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\) for 24 h in DMEM, 10% FBS. After that period, the medium was removed and cells were treated for 1 h with 100 \(\mu\)L of each extract (E1--0.01 mg\(\cdot\)mL\({}^{-1}\), E2--0.062 mg\(\cdot\)mL\({}^{-1}\), E3--0.5 mg\(\cdot\)mL\({}^{-1}\), E4--0.5 mg\(\cdot\)mL\({}^{-1}\), E5--0.25 mg\(\cdot\)mL\({}^{-1}\), and E6--0.5 mg\(\cdot\)mL\({}^{-1}\), diluted in PBS) and then exposed for 40 min to UVA radiation (200 mJ/cm\({}^{2}\)) using a sun simulator chamber (UVA Cube 400, SOL500, Honle UV Technology, Grafelfing, Germany) equipped with a UVA filter (H1) (Honle UV Technology, Grafelfing, Germany) and a UVA sensor (FS UV-A D0, Honle UV Technology, Grafelfing, Germany) with a spectral range of 330-400 nm. After the exposure period, extracts were removed and the wells were washed with PBS, substituted by new medium and incubated at 37 \({}^{\circ}\)C in 5% CO\({}_{2}\) for 24 h. After the incubation period, the medium was removed by aspiration and washed with 100 \(\mu\)L of PBS and the cytotoxicity was evaluated following the neutral red assay described above. PBS supplemented with the respective concentration of DMSO present in each sample and DMEM medium were used as positive controls and DMSO and empty wells were used as negative controls. Each condition was tested using 6 technical replicates and 3 independent assays.