Cytoprotective effect of the enzyme-mediated polygallic acid on fibroblast cells under exposure of UV-irradiation

•Oxidative polymerization of gallic acid gives a novel molecule with biological properties.•Poly(gallic acid) is water soluble and has antioxidant and antimicrobial properties.•Poly(gallic acid) presents cytoprotective effect on fibroblast cells under UV radiation.•Cytoprotective effect reduce ROS presence in cells.

The poly(gallic acid), produced by laccase-mediated oxidation of gallic acid in aqueous media (pH 5.5) to attain a novel material with well-defined molecular structure and high water solubility (500 mg/mL at 25 °C), has been investigated to understand its potential biological activities. In this regard, a biomedical approach based on cytoprotective effect on human fibroblast cells exposed to UV-irradiation in the presence of the polymer has been demonstrated. The results also shows that 200 μg/mL of poly(gallic acid) inhibits the growth and migration of dermal fibroblasts and cancer cell lines without affecting cell viability. Poly(gallic acid) pretreatment with 10 μg/mL protects dermal fibroblasts from UV induced cell death and additionally, the cytoprotective effect reduce ROS presence in the cells. This property can be correlated with the antioxidant power (IC50 of 23.5 μg/mL) of this novel material, which was ascertained by electronic paramagnetic resonance spectroscopy and spectrophotometrically. Additionally, the antimicrobial activity of this material was corroborated with the inhibition of Staphylococcus aureus (ATCC 25923) and Enterococcus faecalis (ATCC 29212) strains (MIC = 400 mg/mL) common bacteria found in hospitals.