Inhibitory property of the Piper betel phenolics against photosensitization-induced biological damages

The Piper betel phenolics, allylpyrocatechol (APC) and chavibetol (CHV), were found to protect photosensitization-mediated lipid peroxidation (LPO) of rat liver mitochondria effectively, APC being significantly more potent. The better activity of APC vis-a-vis CHV could be attributed to its higher reactivity with O-1(2), as revealed from the rate constant values of O-2 quenching by the respective phenolics. APC also prevented the detrimental effects of the Type II photosensitization-induced toxicity to mouse fibroblast L929 cells. The results suggest that APC may play an important role in protecting biological systems against damage, by eliminating O-1(2) generated from certain endogenous photosensitizers. (C) 2008 Elsevier Ltd. All rights reserved.