Evaluation of phototoxic potential of aerial components of the fig tree against human melanoma

Objectives: To date, Ficus carica L. cultivar Dottato (F. carica) has not been studied from a phototoxic point of view. In the present work, aerial components of F. carica from Italy, were examined to assess their antioxidant and phototoxic activity on human melanoma cells. A relationship between antioxidant, phototoxic activities and chemical composition has also been investigated. Materials and methods: Coumarin and fatty acid content in F. carica leaves, bark and woody parts were examined and compared by capillary GC and GC/MS. Polyphenolic content was also determined. Linoleic acid peroxidation and DPPH test were used to assess antioxidant activities, and MTT assay was used to evaluate anti-proliferative activity, on C32 human melanoma cells, after irradiation with a UVA dose of 1.08 J/cm2. Results: Leaves demonstrated the best antioxidant and anti-proliferative activity in comparison to bark and wood. In particular, leaves were shown to possess the highest anti-radical activity and inhibition of peroxidation, with IC50 values of 64 and 1.48 microg/ml respectively. The leaves had highest anti-proliferative activity with IC50 value of 3.92 microg/ml. The phytochemical investigation revealed different composition between the coumarins, psoralen and bergapten, fatty acids, polyphenols and flavonoid content among plant parts. Conclusions: Data obtained indicate that this type of fig tree may constitute an excellent source of bioactive compounds, such as phenolics, coumarins and fatty acids. This study offers a new perspective in developing others formulations potentially useful in photodynamic therapy for treatment of nonmelanoma skin cancers.