The prenylated benzoquinone coenzyme Q or ubiquinone is a vital electron and proton carrier in the respiratory chain of mitochondria and some bacteria (Nowicka and Kruk,2010).Due to its highly hydrophobic nature,ubiquinone can freely migrate in mitochondrial inner membrane carrying one or two electrons from either NADH dehydrogenase (complex Ⅰ) or succinate dehydrogenase (complex Ⅱ) to cytochrome bc1 complex (complex Ⅲ).In plants,ubiquinone can additionally be reduced and oxidized by alteative NAD(P)H dehydrogenases and alteative oxidase,respectively.