Bisphenol A (BPA), a representative endocrine disrupting chemicals, has adverse effects on growth, development and reproduction in aquatic organisms. The object of this study was to investigate the modulation of antioxidant enzyme - coding genes using quantitative real time RT - PCR (qRT - PCR), enzyme activity and total protein content, to understand oxidative stress responses after exposure to BPA for 48 h in brackish water flea Diaphanosoma celebensis. The BPA (3 mg L-1) significantly upregulated the expression of Cu / Zn - SOD, Mn-SOD, and catalase (CAT ) mRNA. Three GST isoforms (GST-kappa, GST-mu, and GST-theta) mRNA levels significantly increased at the rate of 0.12 mg L-1 of BPA. In particular, GST-mu showed the highest expression level, indicating its key role in antioxidant response to BPA. SOD activity was induced with a concentration - dependent manner, and total protein contents was reduced. These findings indicate that BPA can induce oxidative stress in this species, and these antioxidants may be involved in cellular protection against BPA exposure. This study will provide a better understanding of molecular mode of action of BPA toxicity in aquatic organisms.

[6]-Gingerol, a major polyphenol of ginger(Zingiber officinale), exhibits a variety ofbiological properties including anti-oxidant, anti-inflammatory and anti-cancer activity. However,the radioprotective effect of [6]-gingerol is still unknown. The aim of this study was to investigatethe radioprotective effect of [6]-gingerol against radiation-induced cell cytotoxicity and oxidativestress in HepG2 cells. [6]-Gingerol pretreatment attenuated radiation-induced cell cytotoxicitycaused by 5Gy(half lethal dose, LD50of HepG2 cells). The measurements of superoxide dismutase(SOD) and catalase(CAT) activity were also performed. The results showed that [6]-gingerol pre-treatment reduced increasing SOD and CAT activity after exposure of IR, indicating that [6]-gin-gerol protected oxidative stress by regulating cellular antioxidant enzyme(SOD and CAT) activity.These findings suggest that [6]-gingerol acts as a radioprotector by attenuating cell cytotoxicityand oxidative stress.