Abstract: Antioxidant enzymes play a significant part in reactive oxygen scavenger and antioxidant defense systems. With increasing attentions to environmental problems, antioxidant enzymes have been widely used as the biomarkers for diagnosing environmental contamination and assessing the toxic effects of pollutants on living organisms. In this review, the varieties and characters of antioxidant enzymes were introduced, with their combined effects discussed. The responses of antioxidant enzyme activity and gene expression to environmental contamination were analyzed based on different pollutant exposures, and some factors affecting the enzymes were summarized from the aspects of species sensitivity and environmental condition. The focuses of further studies on the effective biomarkers for diagnosing environmental contamination were put forward.

Key words: Arundo donax, Heavy metal pollution, Phytoremediation, Tolerance