The high antioxidant activities of the boiled and ethanolic extracts of the leafy materials were probably due to the extracted tannins and photosynthetic pigments. Cortex Magnoliae Officinalis is a rich source for antioxidative compounds, such as biphenols, polyphenols and tannins [42, 43] . Lo et al. found that the antioxidant effects of magnolol and honokiol isolated from Cortex Magnoliae Officinalis were 1000 times higher than those of alphatocopherol [44] . Earlier studies confirmed that several naturally occurring dietary phytochemicals, such as isothiocyanates, curcumin and Epigallocatechin-3-gallate, possessed cancer preventive properties [45, 46] .