Antioxidant prenylated phenols of Artocarpus plants attenuate ultraviolet radiation-induced damage on human keratinocytes and fibroblasts

Abstract Two novel prenylated phenols, cyclocomunoindenol ( 1 ) and cyclocomunohexanol ( 2 ) were isolated from the cortex of roots of Artocarpus communis . Their structures were determined by spectroscopic methods. Compounds 2 and 6 revealed significant DPPH -scavenging activity with an IC 50 values of 435.48 ± 0.93 and 53.55 ± 8.73 μM, respectively. Compounds 1 , 2 , and 6 displayed significant ABTS + scavenging activity with an IC 50 values of 164.26 ± 2.44, 227.01 ± 3.64, and 44.09 ± 0.88 μM, respectively. Compound 6 exhibited an inhibitory effect on XO activity with an IC 50 value of 10.91 ± 1.77 μM and the relative oxygen radical absorbance capacity (ORAC) values of 1 – 6 , using ORAC-pyrogallol red (PGR) assay, were determined to be 0.28 ± 0.06, 0.31 ± 0.02, 0.55 ± 0.25, 0.84 ± 0.36, 0.35 ± 0.15, and 0.70 ± 0.09, respectively. Antioxidants 5 and 6 significantly attenuate UVA radiation-induced damage on human HaCaT keratinocytes and Hs68 fibroblasts. These finding showed that 1 – 6 may be used as antioxidants and 5 and 6 may protect skin against the adverse effects of UV radiation.