Effect of Microwave Radiation on the Antioxidant Responses of Nannochloropsis oculata

Microwave radiation has a variety of biological effects. In this study, the biological effects of microwave radiation on a marine alga Nannochloropsis oculata were investigated. The results showed that the electrolyte leakage in the microwave treated group was increased 107.7%, compared with the untreated group. A significant increase (P<;0.01) of the activity of superoxide dismutase by 20.6%, catalase by 55.5%, glutathione peroxide by 27.1%, membrane bound Na⁺/K⁺-ATPase and Ca²⁺/Mg²⁺-ATPase by 47.9% and 47.6% in the microwave treated microalga were observed. Microwave radiation also significantly enhanced the ability of the hydroxyl radical scavenging (P<;0.01) and the production of carotenoids. These results suggested that efficient antioxidant defense plays an important role in microwave treated Nannochloropsis oculata, the algal cells could improve their antioxidant ability through the enhancement of enzymatic and non-enzymatic preventive substances and cause resistance to environmental stresses like microwave irradiation.