Of the 12 biochemical indicators the transaminases AST and ALT are two enzymes that are associated with hepatocellular damage and so are used as biomarkers for predicting possible toxicity (Huang et al., 2006; Ojiako and Nwanyo, 2006). Although both are common liver enzymes and their concentration in hepatocytes is high, only ALT is remarkably specific for liver function since AST is mostly present in myocardium, skeletal muscles, brain and kidneys (Sacher and McPherson,1991; Witthawaskul et al., 2003).