PURPUROGALLIN, A SCAVENGER OF POLYMORPHONUCLEAR LEUKOCYTE-DERIVED OXYRADICALS

Purpurogallin (PPG) is a phenolic compound extracted from nutgalls for med on oak trees. It has been used as an additive to edible or nonedib le oils or fats, and to hydrocarbon fuels or lubricants to retard thei r oxidation. We investigated by luminol-dependent chemiluminescence (P MNL-CL), the ability of PPG to scavenge oxygen free radicals (OFRs) ge nerated by zymosan-activated polympophonuclear leukocytes (PMNLs). Its OFR-scavenging ability was also investigated by the use of nitro blue tetrazolium (NBT). We also investigated by the dye-exclusion method, if PPG affects the viability of PMNLs. PPG in the concentrations of 0. 005-0.4 mM was used in this study. PPG scavenged OFRs produced by zymo san-activated PMNLs in a concentration-dependent manner. Almost comple te scavenging was observed at a concentration of 0.2 mM. The NBT test indicated that PPG (0.2 mM) did not completely prevent the activation of PMNLs by zymosan. Viability of PMNLs in the absence or presence of PPG (0.4 mM) were 95.77 +/- 0.56% and 96.78 +/- 0.60% respectively. Th e results suggest that PPG scavenges OFRs produced from activated PMNL s in a concentration-dependent manner and that the cell viability is n ot affected by PPG. PPG is a potent scavenger of OFRs and should be of value in the prevention and treatment of diseases in the pathophysiol ogy of which OFRs are involved.