SOD activity and extremophilicity: a screening of various plant species.

All aerobes are dependent on enzymatic and non-enzymatic antioxidants to withstand the presence of reactive oxygen species (ROS). Superoxide dismutase (SOD) is a part of the enzymatic antioxidant system. It is one of the most important antioxidant enzymes, enabling organisms to survive in an oxygen containing atmosphere. A disorder in the oxidative and antioxidative balance can be associated with the occurrence of diseases in human organisms. Little data exist on the relevance of SOD in plants. Moreover, it is not known whether there is any association between a plant's origin and its SOD activity. Our screening of 27 different plant species was intended to expose whether there is a connection. The highest SOD activities were found for extremophile plants. Especially the Crassulaceae Aeonium haworthii Salm-Dyck Ex Webb & Berthel. and Crassula multiflora Schönland & Baker F. were highly active. Nevertheless, we did not find unambiguous evidence for a correlation between extremophilicity and SOD activity.